A Phase 2, Randomized, Parallel, Open-label Study to Investigate the Safety, Efficacy, and Pharmacokinetics of Various Dosing Regimens of Single-agent Belantamab Mafodotin (GSK2857916) in Participants With Relapsed or Refractory Multiple Myeloma (DREAMM-14)
Phase: PHASE2
Conditions: Multiple Myeloma
Sponsor: GlaxoSmithKline

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TITLE PAGE 
Protocol Title: A Phase 2, Randomized, Parallel, Open-Label Study to Investigate the 
Safety, Efficacy, and Pharmacokinetics of Various Dosing Regimens of Single-Agent 
Belantamab Mafodotin (GSK2857916) in Participants with Relapsed or Refractory 
Multiple Myeloma (DREAMM-14) 
Protocol Number: 209628 / Amendment 03 
Compound Number: GSK2857916 
Brief Title: 
Study to Investigate Alternative Dosing Regimens of Belantamab Mafodotin in 
Participants with Relapsed or Refractory Multiple Myeloma (DREAMM-14) 
Study Phase: Phase 2 
Sponsor Name and Legal Registered Address: 
GlaxoSmithKline Research & Development Limited 
980 Great West Road 
Brentford 
Middlesex, TW8 9GS 
UK 
SPONSOR SIGNATORY: 
Sumita Roy-Ghanta, MD 
Group Senior Medical Director Clinical Development Lead 
Belantamab Mafodotin Program 
Approval Date: 25 Jun 2024 
Regulatory Agency Identifying Numbers: 
Registry 
ID 
IND 
119333 
EU CT number 
2023-508213-16-00 
©2024 GSK group of companies or its licensor. All rights reserved. Unauthorized 
copying or use of this information is prohibited

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Protocol/Protocol Amendment 3 Investigator Agreement 
I agree: 
• 
To assume responsibility for the proper conduct of the study at this site. 
• 
That I am aware of and will comply with GCP and all applicable regulatory 
requirements. 
• 
That I will comply with the terms of the clinical study site agreement. 
• 
To ensure that all persons assisting me with the study are adequately informed about 
the GSK study intervention and other study-related duties and functions as described 
in the protocol. 
• 
To cooperate with representative(s) of GSK in the monitoring and data management 
processes of the study with respect to data entry and resolution of queries about the 
data. 

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Protocol Amendment 3 Final  
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Study identifier 
209628  
Abbreviated title 
DREAMM-14 
EU CT number 
2023-508213-16-00 
Approval date 
25 Jun 2024 
 
 
Title 
A Phase 2, Randomized, Parallel, Open-Label Study 
to Investigate the Safety, Efficacy, and 
Pharmacokinetics of Various Dosing Regimens of 
Single-Agent Belantamab Mafodotin 
(GSK2857916) in Participants with Relapsed or 
Refractory Multiple Myeloma (DREAMM-14) 
Investigator name 
 
 
 
Signature 
 
 
 
Date of signature 
(DD Month YYYY) 
 
 
 
 

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PROTOCOL AMENDMENT SUMMARY OF CHANGES 
DOCUMENT HISTORY 
Document 
Date 
Document Identifier 
Amendment 03 
25 Jun 2024 
TMF-19107833 
Amendment 02 GBR-1 
20-December-2022 
TMF-15222732 
Amendment 02 
19-December-2022 
TMF-14902500 
Amendment 01 GBR-1 
04-May-2022 
TMF-14578074 
Amendment 01 FRA-1 
27-January-2022 
TMF-14396610 
Amendment 01 
21-January-2022 
TMF-14343018 
Original Protocol (00) 
14-September-2021 
TMF-13844035 
Amendment 03 (25 Jun 2024) 
This amendment is considered to be substantial based on the criteria set forth in 
Article 10(a) of Directive 2001/20/EC of the European Parliament and the Council of the 
European Union. 
Overall rationale for the amendment 
This protocol amendment 03 is a global amendment to address editorial changes to align 
with the new Sponsor’s standard protocol template and ways of working. Flexibility 
regarding the post-analysis continued treatment (PACT) period was incorporated into the 
language. Additionally, updates were made to allow flexibility for the end of treatment 
(EOT) visits, ocular examinations, short term use of steroids and sample collection 
windows. Safety information was also updated following the DREAMM-2 study 
completion. The third parties and subcontractors’ appendix is now a separate document. 
A description and rationale for all changes is provided in the table that follows. 

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Section # and name 
Description of change 
Brief rationale 
Section 1.1 Synopsis 
Added flexible language 
for PACT 
To allow flexibility for participants to 
move into PACT period after study 
completion 
Section 1.3 Schedule 
of Activities (Table 1) 
Included additional details 
for the EOT Visit definition 
Clarification of the EOT Visit definition 
Updated footnote 9  
Clarification of the scope of the ocular 
assessments following EOT 
Section 1.3 Schedule 
of Activities (Table 4) 
Updated sample collection 
window  
Alignment with visit windows  
Section 2.2.3 Clinical 
Experience with 
Belantamab Mafodotin 
relevant for DREAMM-
14 
Heading text update 
Clarification as to why only DREAMM-1 
and DREAMM-2 data are included 
Content update following 
completion of DREAMM-2 
study 
Added clinical experience with 
belantamab mafotodin 
Section 2.3.1 Risk 
Assessment 
Updated numbers in table 
of risk assessment for 
thrombocytopenia 
Added clinical experience with 
belantamab mafotodin from study 
205678 
Section 4.1 Overall 
Design 
Section 4.6 End of 
Study Definition/Study 
Completion  
Added flexible language 
for PACT 
To allow flexibility for participants to 
move into PACT period after study 
completion 
Section 4.5 Participant 
Completion 
Removed “If a participant 
has been in follow-up for 
2 years at the final OS 
analysis (see Section 4.6) 
or if the participant dies 
during the study treatment 
or follow-up period, that 
participant is considered to 
have completed the study. 
The cause of death should 
be documented in the 
electronic Case Report 
Form (eCRF).” wording  
To align with PACT language 
Section 4.6 End of 
Study Definition/Study 
Completion 
Added “and PFS , as well 
as selected safety data” for 
the final analysis  
Update in scope of final analysis 
Section 5 Study 
Population 
Subheaders were added 
for the inclusion and 
exclusion criteria 
Editorial changes to align with the 
Sponsor’s standard protocol 
Section 6.6.1 
Continued Access to 
Study Treatment After 
the Final Data Cutoff 
Added flexible language 
for PACT 
To allow flexibility for participants to 
move into PACT period after study 
completion 

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Section # and name 
Description of change 
Brief rationale 
prior to End of the 
Study 
Section 6.8.2 
Prohibited Medications 
and Non-Drug 
Therapies 
Added exception to the 
use of steroid for adverse 
event or emergency 
situations 
To allow flexibility considering the sick 
patient population and short term use of 
steroids intravenously 
Updated the anti-HIV 
drugs sentence 
Clarification for study conduct 
Section 7.2 Participant 
Discontinuation/Withdr
awal from the clinical 
study 
Added language on use of 
public sources for vital 
status information 
collection 
Clarification for study conduct 
Section 8.3.5 Ocular 
Examinations 
Updated the text on 
ophthalmic medical follow-
up after EOT 
Clarification of the scope of the ocular 
assessments following EOT 
Section 8.4.1 Time 
Period and Frequency 
for Collecting Adverse 
Event and Serious 
Adverse Event 
Information 
Added flexible language 
for a managed access 
program/drug supply 
program 
To allow flexibility for participants to 
continue receiving treatment via a 
managed access program/drug supply 
program after study completion 
Updated the ocular exam 
schedule after end of 
PACT treatment wordings  
Program-level updates  
Section 8.4.4 Adverse 
Events of Special 
Interest 
Section was moved up 
Editorial changes to align with the 
Sponsor’s standard protocol 
Section 8.4.5 
Regulatory reporting 
requirements for 
SAEs/AESIs 
Added Table 13 
Timeframes for submitting 
SAE, pregnancy and other 
events reports to GSK 
Table added to align with the Sponsor’s 
standard protocol template and ways of 
working 
Section 8.4.8 Disease-
Related Events and/or 
Disease-Related 
Outcomes Not 
Qualifying as Serious 
Adverse Events 
Reference to DRE CRF 
pages was removed 
Not applicable for this study 
Section 8.9 
Immunogenicity 
Assessments 
Removal of “A final ADA 
sample will be drawn at 
the EOT visit” sentence 
To align with Schedule of Activities 
Added language that 
sample collection may be 
terminated early 
Allow flexibility  
Section 9.4.5 
Pharmacokinetic 
Analyses 
“Clinical Pharmacoketics” 
was updated to “Clinical 
Pharmacology” 
Correction of GSK department name 

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Section # and name 
Description of change 
Brief rationale 
Section 10.10.3 
Informed Consent 
Process 
Added text regarding 
collection of pregnancy for 
both maternal and paternal 
exposure 
To align with the Sponsor’s standard 
protocol 
Section 10.10.5 
Committees Structure 
Added paragraph on 
Safety Review Team  
To align with the Sponsor’s standard 
protocol 
Third Parties and 
Subcontractors 
Appendix  
Appendix was removed 
from Protocol Amendment 
3 
To align with the Sponsor’s standard 
protocol template and ways of working, a 
separate document has been created 
Section 10.20 
Appendix 20: 
Abbreviations, and 
Trademarks and 
Definitions of Terms 
Updated to include 
definitions of terms table 
To align with the Sponsor’s standard 
protocol template and ways of working 
Throughout the 
document 
Editiorial and document 
formatting changes 
Editorial changes to align with the new 
Sponsor’s standard protocol template 
and ways of working 
Abbreviations: ADA: anti drug antibody; AESI: adverse event of special interest; 
eCRF: electronic Case Report Form; EOT: End of Treatment; HIV: human immunodeficiency 
virus; OS: overall survival; PACT: Post Analysis Continued Treatment; PFS: progression free 
survival; SAE: serious adverse event 

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TABLE OF CONTENTS 
PAGE 
PROTOCOL/PROTOCOL AMENDMENT 3 INVESTIGATOR AGREEMENT .................. 2 
PROTOCOL AMENDMENT SUMMARY OF CHANGES ................................................. 4 
1. 
PROTOCOL SUMMARY ........................................................................................ 14 
1.1. 
Synopsis ..................................................................................................... 14 
1.2. 
Schema ...................................................................................................... 20 
1.3. 
Schedule of Activities (SoA) ........................................................................ 21 
2. 
INTRODUCTION .................................................................................................... 31 
2.1. 
Study Rationale .......................................................................................... 31 
2.2. 
Background ................................................................................................ 32 
2.2.1. 
Multiple Myeloma ......................................................................... 32 
2.2.2. 
Antibody-Drug Conjugate Belantamab Mafodotin ........................ 32 
2.2.3. 
Clinical Experience with Belantamab Mafodotin relevant 
for DREAMM-14 .......................................................................... 33 
2.3. 
Benefit/Risk Assessment ............................................................................ 38 
2.3.1. 
Risk Assessment ......................................................................... 39 
2.3.2. 
Benefit Assessment ..................................................................... 41 
2.3.3. 
Overall Benefit/Risk Conclusion ................................................... 41 
3. 
OBJECTIVES AND ENDPOINTS AND ESTIMANDS ............................................. 42 
4. 
STUDY DESIGN .................................................................................................... 46 
4.1. 
Overall Design ............................................................................................ 46 
4.2. 
Scientific Rationale for Study Design .......................................................... 47 
4.2.1. 
Participant Input into Study Design .............................................. 48 
4.3. 
Justification for Selected Doses and Schedules .......................................... 48 
4.4. 
Rationale for the Investigation of Symptom-Based Dose 
Modifications (Arm E).................................................................................. 49 
4.5. 
Participant Completion ................................................................................ 51 
4.6. 
End of Study Definition/Study Completion ................................................... 51 
5. 
STUDY POPULATION ........................................................................................... 52 
5.1. 
Inclusion Criteria ......................................................................................... 52 
5.1.1. 
Age .............................................................................................. 52 
5.1.2. 
Type of Participant and Disease Characteristics .......................... 52 
5.1.3. 
Sex and Contraceptive/Barrier Requirements .............................. 53 
5.1.4. 
Informed Consent ........................................................................ 54 
5.1.5. 
Other Inclusions ........................................................................... 54 
5.2. 
Exclusion Criteria ........................................................................................ 55 
5.2.1. 
Medical Conditions ...................................................................... 55 
5.2.2. 
Liver Safety .................................................................................. 56 
5.2.3. 
Prior/Concomitant Therapy .......................................................... 57 
5.2.4. 
Diagnostic Assessments .............................................................. 57 
5.3. 
Lifestyle Considerations .............................................................................. 58 
5.4. 
Screen Failures........................................................................................... 58 
5.5. 
Criteria for Temporarily Delaying Enrollment, Randomization, or 
Administration of Study Treatment .............................................................. 58 

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6. 
STUDY TREATMENT AND CONCOMITANT THERAPY ....................................... 58 
6.1. 
Study Treatments Administered .................................................................. 58 
6.1.1. 
Belantamab Mafodotin ................................................................. 59 
6.2. 
Preparation, Handling, Storage, and Accountability .................................... 60 
6.3. 
Assignment to study intervention ................................................................ 60 
6.4. 
Study Treatment Compliance ...................................................................... 61 
6.5. 
Dose Modification (Dose Reductions and Dose Delays) ............................. 61 
6.5.1. 
Dose Modification for Corneal Events (Arms A to D) .................... 62 
6.5.2. 
Dose Modifications Based on Ocular Symptoms, Visual 
Acuity Assessments, and Corneal Findings (Arm E) .................... 64 
6.5.3. 
Dose Modification for Treatment-Related Non-Ocular 
Adverse Events (All Arms) ........................................................... 65 
6.5.4. 
Management of and Dose Modification for Participants 
with Hepatitis B Virus ................................................................... 69 
6.6. 
Continued Access to Study Treatment after the End of the Study ............... 69 
6.6.1. 
Continued Access to Study Treatment After the Final Data 
Cutoff prior to End of the Study .................................................... 70 
6.7. 
Treatment of Overdose ............................................................................... 70 
6.8. 
Concomitant Therapy.................................................................................. 71 
6.8.1. 
Ocular Supportive Care: Guidelines and Prophylactic 
Measures ..................................................................................... 71 
6.8.2. 
Prohibited Medications and Non-Drug Therapies ......................... 72 
7. 
DISCONTINUATION OF STUDY TREATMENT AND PARTICIPANT 
DISCONTINUATION/WITHDRAWAL ..................................................................... 74 
7.1. 
Discontinuation of Study Treatment ............................................................ 74 
7.1.1. 
Liver Chemistry Stopping Criteria ................................................ 75 
7.1.2. 
Corneal Event Stopping Criteria ................................................... 76 
7.1.3. 
Infusion-Related Reaction Management and Stopping 
Criteria ......................................................................................... 77 
7.1.4. 
Allergic and Anaphylactic Reaction Stopping Criteria ................... 77 
7.1.5. 
Rechallenge ................................................................................. 77 
7.2. 
Participant Discontinuation/Withdrawal from the clinical Study .................... 78 
7.3. 
Lost to Follow-Up ........................................................................................ 79 
8. 
STUDY ASSESSMENTS AND PROCEDURES ..................................................... 80 
8.1. 
Administrative and general procedures ....................................................... 80 
8.2. 
Efficacy Assessments ................................................................................. 81 
8.2.1. 
Response Evaluation ................................................................... 82 
8.3. 
Safety Assessments ................................................................................... 82 
8.3.1. 
Physical Examinations ................................................................. 82 
8.3.2. 
Vital Signs .................................................................................... 82 
8.3.3. 
Electrocardiograms ...................................................................... 83 
8.3.4. 
Eastern Cooperative Oncology Group Performance Status ......... 83 
8.3.5. 
Ocular Examinations .................................................................... 83 
8.3.6. 
Clinical Safety Laboratory Tests .................................................. 85 
8.3.7. 
Pregnancy Testing ....................................................................... 85 
8.3.8. 
Suicidal Ideation and Behavior Risk Monitoring ........................... 86 
8.4. 
Adverse Events, Serious Adverse Events, and Other Safety 
Reporting .................................................................................................... 86 
8.4.1. 
Time Period and Frequency for Collecting Adverse Event 
and Serious Adverse Event Information ....................................... 86 

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8.4.2. 
Method of Detecting Adverse Events and Serious Adverse 
Events ......................................................................................... 88 
8.4.3. 
Follow-up of Adverse Events and Serious Adverse Events .......... 88 
8.4.4. 
Adverse Events of Special Interest .............................................. 88 
8.4.5. 
Regulatory reporting requirements for SAEs/AESIs ..................... 89 
8.4.6. 
Pregnancy ................................................................................... 89 
8.4.7. 
Cardiovascular and Death Events ................................................ 90 
8.4.8. 
8.4.9. 
Medical device deficiencies ......................................................... 91 
8.5. 
Pharmacokinetics ....................................................................................... 91 
8.5.1. 
Blood Sample Collection for Pharmacokinetics ............................ 91 
8.5.2. 
Pharmacokinetic Sample Analysis ............................................... 91 
8.6. 
Genetics ..................................................................................................... 92 
8.7. 
Biomarkers/Translational Research ............................................................ 92 
8.7.1. 
Soluble B-Cell Maturation Antigen ............................................... 93 
8.7.2. 
Tumor Biomarker Analysis ........................................................... 93 
8.7.3. 
RNA Transcriptome Research ..................................................... 93 
8.8. 
T, B, and Natural Killer Cells ....................................................................... 94 
8.9. 
Immunogenicity Assessments ..................................................................... 94 
8.10. 
Patient-Reported Outcomes........................................................................ 94 
8.10.1. 
Treatment and Tolerability-Related Patient-Reported 
Outcomes .................................................................................... 95 
8.10.2. 
Health-Related Quality of Life ...................................................... 96 
9. 
STATISTICAL CONSIDERATIONS AND DATA ANALYSES ................................. 98 
9.1. 
Statistical Hypothesis .................................................................................. 98 
9.2. 
Sample Size Considerations ....................................................................... 98 
9.2.1. 
Sample Size Assumptions: Primary Endpoint .............................. 98 
9.2.2. 
Safety Stopping Rule for Arm E ................................................. 100 
9.3. 
Data Analysis Considerations ................................................................... 101 
9.3.1. 
Analysis Populations .................................................................. 101 
9.4. 
Key Elements of Statistical Analysis Plan ................................................. 101 
9.4.1. 
Dosing Based on Baseline Disease Characteristics – 
Virtual Treatment Arm ................................................................ 102 
9.4.2. 
General Considerations ............................................................. 102 
9.4.3. 
Safety Analyses ......................................................................... 102 
9.4.4. 
Efficacy Analyses ....................................................................... 105 
9.4.5. 
Pharmacokinetic Analyses ......................................................... 106 
9.4.6. 
Pharmacokinetic/Pharmacodynamic Analyses ........................... 107 
9.4.7. 
Biomarker/Translational Research Analyses .............................. 107 
9.4.8. 
Patient-Reported Outcomes Analyses ....................................... 108 
9.5. 
Interim Analysis ........................................................................................ 108 
9.5.1. 
Independent Data Monitoring Committee ................................... 108 
10. SUPPORTING DOCUMENTATION AND OPERATIONAL 
CONSIDERATIONS ............................................................................................. 109 
10.1. 
Appendix 1: Eye Care Specialist’s Qualifications and Requirements ........ 109 
10.2. 
Appendix 2: International Staging System for Multiple Myeloma ............... 110 
10.3. 
Appendix 3: Guidelines for the Determination of the Number of Prior 
Lines of Therapy in Multiple Myeloma ....................................................... 111 
10.4. 
Appendix 4: Decentralized and Remote Assessment Approaches ............ 113 
CCI

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10.5. 
Appendix 5: Modified Diet in Renal Disease Formula................................ 114 
10.6. 
Appendix 6: Liver Safety Required Actions and Follow-Up 
Assessments ............................................................................................ 115 
10.7. 
Appendix 7: Country-Specific Requirements ............................................. 118 
10.8. 
Appendix 8: Eastern Cooperative Oncology Group (ECOG) 
Performance Status .................................................................................. 119 
10.9. 
Appendix 9: Contraceptive and Barrier Guidance ..................................... 120 
10.9.1. 
Definitions .................................................................................. 120 
10.9.2. 
Contraception Guidance ............................................................ 122 
10.10. Appendix 10: Regulatory, Ethical, and Study Oversight 
Considerations .......................................................................................... 123 
10.10.1. Regulatory and Ethical Considerations ...................................... 123 
10.10.2. Financial Disclosure ................................................................... 123 
10.10.3. Informed Consent Process ........................................................ 124 
10.10.4. Data Protection .......................................................................... 125 
10.10.5. Committees Structure ................................................................ 125 
10.10.6. Dissemination of Clinical Study Data ......................................... 125 
10.10.7. Data Quality Assurance ............................................................. 126 
10.10.8. Source Documents .................................................................... 127 
10.10.9. Study and Site Start and Closure ............................................... 127 
10.10.10. Publication Policy ....................................................................... 128 
10.11. Appendix 11: New York Heart Association Classification .......................... 129 
10.12. Appendix 12: Liver Safety Drug Restart or Rechallenge Guidelines .......... 130 
10.13. Appendix 13: Clinical Laboratory Tests ..................................................... 133 
10.14. Appendix 14: Adverse Events and Serious Adverse Events: 
Definitions and Procedures for Recording, Evaluating, Follow-up, 
and Reporting ........................................................................................... 135 
10.14.1. Definition of Adverse Event ........................................................ 135 
10.14.2. Definition of Serious Adverse Event ........................................... 136 
10.14.3. Definition of Cardiovascular Events ........................................... 136 
10.14.4. Recording and Follow-Up of Adverse Events and Serious 
Adverse Events.......................................................................... 137 
10.14.5. Reporting of Serious Adverse Events to GlaxoSmithKline ......... 138 
10.15. Appendix 15: Genetics .............................................................................. 139 
10.16. Appendix 16: Operating Characteristics of the Safety Stopping Rule 
for Arm E .................................................................................................. 140 
10.17. Appendix 17: Data Management/Monitoring ............................................. 141 
10.18. Appendix 18: Progression-Free Survival Event and Censoring Rules ....... 142 
10.19. Appendix 19: Visual Acuity Conversion ..................................................... 144 
10.20. Appendix 20: Abbreviations,Trademarks and Definitions of Terms ........... 145 
10.21. Appendix 21: Protocol Amendment History ............................................... 150 
10.22. Appendix 22: French-Specific Requirements ............................................ 161 
11. REFERENCES ..................................................................................................... 164 
 
 
 

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LIST OF TABLES 
PAGE 
Table 1 
Schedule of Activities: Screening, On-Treatment, End of 
Treatment, and Follow-Up Assessments – ALL ARMS........................... 22 
Table 2 
Additional Assessments for Participants with HBV ................................. 29 
Table 3 
Additional Assessments for Participants with HCV ................................. 29 
Table 4 
Collection Schedule for PK, sBCMA, and ADA Samples – ALL 
ARMS .................................................................................................... 30 
Table 5 
Criteria for Determining HBV Status ....................................................... 56 
Table 6 
Study Arms and Treatment Administered (Belantamab 
Mafodotin) .............................................................................................. 59 
Table 7 
Methods to Minimize Bias ...................................................................... 61 
Table 8 
KVA Scale and Dose Modification Guidelines for Corneal 
Toxicities for Belantamab Mafodotin Treatment for Arms A to D ............ 62 
Table 9 
Dose Modification Guidelines for Belantamab Mafodotin 
Treatment for Arm E based on OSDI, Visual Acuity, and Corneal 
Findings ................................................................................................. 64 
Table 10 
Dose Modification Guidelines for Belantamab Mafodotin-Related 
AEs ........................................................................................................ 65 
Table 11 
General Dose Modification and Management Guidelines for 
Belantamab Mafodotin-Related AEs Not Otherwise Specifieda .............. 68 
Table 12 
Dose Modification Guidelines for HBV Reactivation ............................... 69 
Table 13 
Timeframes for submitting SAE, pregnancy and other events 
reports to GSK ....................................................................................... 89 
Table 14 
Study Safety Operating Characteristics .................................................. 99 
Table 15 
Safety Stopping Rule for Arm E ............................................................ 100 
Table 16 
Definitions of Study Analysis Populations ............................................. 101 
Table 17 
Statistical Analysis Methods: Safety ..................................................... 103 
Table 18 
Statistical Analytical Methods: Efficacy ................................................. 106 
Table 19 
Arm Stopping Probability at Interim Analysis by True Response 
Rate ..................................................................................................... 108 
Table 20 
Protocol-Required Clinical Laboratory Tests ........................................ 133 

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LIST OF FIGURES 
PAGE 
Figure 1 
DREAMM-14 Study Schema .................................................................. 20 
Figure 2 
Belantamab Mafodotin Mechanism of Action .......................................... 33 
Figure 3 
Liver Chemistry Stopping and Increased Monitoring Algorithm ............... 76 

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1. 
PROTOCOL SUMMARY 
1.1. 
Synopsis 
Protocol Title: 
A Phase 2, Randomized, Parallel, Open-Label Study to Investigate the Safety, Efficacy, 
and Pharmacokinetics of Various Dosing Regimens of Single-Agent Belantamab 
Mafodotin (GSK2857916) in Participants with Relapsed or Refractory Multiple Myeloma 
(DREAMM-14) 
Brief Title: 
Study to Investigate Alternative Dosing Regimens of Belantamab Mafodotin in 
Participants with Relapsed or Refractory Multiple Myeloma (DREAMM-14) 
Rationale: 
Belantamab mafodotin (GSK2857916) is a B-cell maturation antigen (BCMA)-directed 
antibody-drug conjugate (ADC) that is conjugated to a microtubule disrupting agent, 
monomethyl auristatin F (MMAF) with antitumor activity in multiple myeloma (MM) 
cells. Belantamab mafodotin mediates the killing of tumor cells through MMAF-induced 
apoptosis as well as by tumor cell lysis through antibody-dependent cellular cytotoxicity 
(ADCC) and antibody-dependent cellular phagocytosis (ADCP). Clinically, single-agent 
belantamab mafodotin has demonstrated efficacy in participants with relapsed or 
refractory multiple myeloma (RRMM) who have received at least 4 prior therapies, 
including an anti-CD38 monoclonal antibody, a proteasome inhibitor, and an 
immunomodulatory agent.  
Efficacy has been demonstrated at 2.5 mg/kg dose of belantamab mafodotin, 
administered as an IV infusion once every 3 weeks (Q3W) until progressive disease (PD) 
or unacceptable toxicity. The Phase 2, open-label, randomized study investigating the 
efficacy and safety of belantamab mafodotin in participants with RRMM (DREAMM-2) 
[Lonial, 2020] met its primary endpoint for overall response rate (ORR) of 31% (n=97, 
97.5% confidence interval [CI]: 20.8%, 42.6%). DREAMM-2 patient-reported outcomes 
(PROs) demonstrated that participants treated with belantamab mafodotin at the dose of 
2.5 mg/kg generally maintained their health-related quality of life (HRQoL) and physical 
functioning while on treatment. Although vision-related- activities can be limited during 
episodes of clinically significant ocular PRO changes, these changes are temporary and 
do not adversely impact overall HRQoL and physical functioning [Popat, 2020]. 
Although belantamab mafodotin has demonstrated efficacy in this population, ocular 
toxicity is common and expected, having been reported in other MMAF-containing 
ADCs [Parrozzani, 2020]. Belantamab mafodotin administered at the dose of 2.5 mg/kg 
Q3W can cause changes in the corneal epithelium resulting in changes in vision. 
Keratopathy (defined as corneal examination findings of microcyst-like- keratopathy, 
which were mapped to the preferred term keratopathy per Medical Dictionary for 
Regulatory Activities [MedDRA]) was the most frequent ocular adverse event (AE) in 
the DREAMM-2 study (71% of participants, with 44% Grade 3 and 1% Grade 4) 

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[Lonial, 2020]. The corneal changes often result in visual acuity changes, with 54% [51 
out of 95] of participants experiencing best corrected visual acuity (BCVA) changes of 
any grade and 31% [29 out of 95] of Grade 3 to 4 [Farooq, 2020]. These ocular toxicities 
resulted in high rates of dose delays (47% [45 out of 95] dose delays due to keratopathy) 
and dose reductions (23% [22 out of 95] dose reductions due to keratopathy). 
Alternative dosing regimens of single-agent belantamab mafodotin will be explored in 
Study 209628 to determine if an improved overall benefit/risk profile can be achieved by 
modifying the belantamab mafodotin dose, schedule, or both. 
In addition to investigating alternative dosing schedules to mitigate the risk of corneal 
toxicity (Arms A to D), Study 209628 will also assess the use of ocular symptoms 
(patient-reported symptoms using the Ocular Surface Disease Index [OSDI]) and visual 
acuity assessments (Snellen chart or equivalent) to inform dose modification decisions 
and assess potential impact on the frequency of ocular examinations conducted by an eye 
care specialist on safety and efficacy for the participant (Arm E). 
Objectives and Endpoints: 
Objectives 
Endpoints 
Primary 
To examine the corneal events associated with 
single-agent belantamab mafodotin using 
alternative dosing regimens in participants with 
RRMM in Arms B to D compared to Arm A 
Incidence rate of Grade ≥2 corneal events according to 
the KVA scale 
Secondary 
To further evaluate the ocular safety and 
tolerability of single-agent belantamab 
mafodotin in all arms 
• 
Cumulative event rate of corneal events to 
Week 16 (KVA scale) 
• 
Incidence rate of corneal events by grade (KVA 
scale) 
• 
Exposure-adjusted incidence rate of corneal 
events by grade (KVA scale) 
• 
Median duration of dose delay 
• 
Percentage of participants requiring dose 
reductions, dose delays, and study treatment 
discontinuation due to corneal events (KVA scale) 
• 
Cumulative incidence of corneal events by grade 
(KVA scale) 
• 
Toxicity Index by assessment/visit 
• 
Duration of corneal events (KVA scale) 
• 
Percentage of time on study with corneal events 
(KVA scale) 
• 
Change in BCVA (ΔlogMAR) 

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16 
Objectives 
Endpoints 
To evaluate the efficacy of single-agent 
belantamab mafodotin in all arms 
• 
ORR, defined as the percentage of participants 
with a confirmed PR or better (i.e., PR, VGPR, CR, 
and sCR) 
• 
Percentage of participants with a confirmed VGPR 
or better (i.e., VGPR, CR, and sCR) 
• 
TTR is defined as the time between the date of 
randomization and the first documented evidence 
of response (PR or better), among participants 
who achieve a response (i.e., confirmed PR or 
better) 
• 
DoR in responders, defined as the time from first 
documented evidence of PR or better until PD or 
death due to any cause 
• 
TTP, defined as the time from randomization until 
the earliest date of documented PD or death due 
to PD 
• 
PFS, defined as the time from randomization until 
the earliest date of documented PD or death due 
to any cause 
• 
OS, defined as the time from randomization until 
the date of death due to any cause 
Note: All efficacy endpoints are based on the 
2016 IMWG Response Criteria 
To evaluate the overall safety and tolerability 
of single-agent belantamab mafodotin in all 
arms 
• 
Instance of AEs (including corneal events) 
(CTCAE Version 5.0) and changes in laboratory 
parameters 
• 
Percentage of participants requiring dose 
reductions, dose delays, and study treatment 
discontinuation due to any AEs (CTCAE 
Version 5.0) 
To assess the pharmacokinetics of 
single-agent belantamab mafodotin in all arms 
Plasma belantamab mafodotin pharmacokinetic 
parameters, as data permit 
To assess anti-drug antibodies against 
single-agent belantamab mafodotin in all arms 
Incidence and titers of ADAs against belantamab 
mafodotin at each ADA time point 
Abbreviations: AE=adverse event; BCVA=best corrected visual acuity; CR=complete response; CTCAE=Common 
Terminology Criteria for Adverse Events; ΔlogMAR=change in logarithm of the minimum angle of resolution; 
DoR=duration of response; FACT-GP5=Functional Assessment of Cancer Therapy – General; 
IMWG=International Myeloma Working Group; KVA=keratopathy visual acuity; ORR=overall response rate; 
OS=overall survival; OSDI=Ocular Surface Disease Index; PD=progressive disease; PFS=progression-free 
survival; PR=partial response; PRO-CTCAE=Patient-Reported Outcomes version of the Common Terminology 
Criteria for Adverse Events; RRMM=relapsed or refractory multiple myeloma; stringent complete response; 
TTP=time to progression; TTR=time to response; VGPR=very good partial response. 

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17 
Overall Design: 
Study 209628 (DREAMM-14) is a Phase 2, randomized, parallel, open-label, study of 
belantamab mafodotin administered as a single-agent to participants with RRMM. The 
study has 5 arms: Arm A, a control arm (2.5 mg/kg Q3W); Arms B through D, 3 arms 
with dosing alternatives; and Arm E, a fifth exploratory arm to evaluate the feasibility of 
dosing 1.9 mg/kg every 6 weeks (Q6W) with dose modifications based on ocular 
symptoms, visual acuity assessments, and corneal findings. All enrolling study sites will 
participate in Arms A to D; site participation in Arm E is optional and based on site 
interest and ability. 
Participants in Arm A will use the DREAMM-2 established 2.5 mg/kg Q3W dosing 
regimen. Participants in Arm C will receive a starting dose at 2.5 mg/kg belantamab 
mafodotin, but dosing will occur at Q6W intervals. Participants in Arms B, D, and E will 
start at a reduced dose of belantamab mafodotin (1.9 mg/kg) and continue dosing at Q3W 
(Arm B) and Q6W (Arms D and E) intervals. Each dosing regimen has 1 allowed dose 
reduction: from 2.5 mg/kg to 1.9 mg/kg in Arms A and C and from 1.9 mg/kg to 
1.4 mg/kg in Arms B, D, and E. 
Participants in all arms will have Q3W ophthalmic examination and monitoring. All 
ophthalmic examinations will be performed by a qualified eye care specialist. 
All arms except Arm E will follow dose modification due to corneal events as per the 
keratopathy visual acuity (KVA) scale. In contrast, Arm E will use a symptom-based 
dose modification approach before each dose, in the oncologist’s office; specifically, 
ocular symptoms and visual acuity assessments using the OSDI and Snellen chart or 
equivalent, respectively (in addition to corneal examination findings according to the 
KVA scale), will be used to inform dose modification decisions. Note: Although not 
determining dose modification decisions, corneal events (corneal findings and BCVA) 
graded per the KVA scale will still be recorded for all participants in Arm E throughout 
the study. 
Participants in all arms will be treated until PD (confirmed by 2016 IMWG response 
criteria [Kumar, 2016]), unacceptable toxicity, or death. The study consists of a 
screening/baseline period, a treatment period, and a post-treatment follow-up period. The 
primary analysis will be performed at least 9 months after the first response of the last 
responder (i.e., partial response [PR], very good partial response [VGPR], complete 
response [CR], and stringent complete response [sCR]) or 12 months after the last 
participant is randomized into Arms A to D, whichever comes first. 
Brief Summary: 
The purpose of the study is to explore whether alternative dosing regimens with lower 
dose intensity of single-agent belantamab mafodotin can improve the benefit/risk profile 
(i.e., can reduce the risk of corneal events without a clinically meaningful decrease in 
efficacy) in participants with RRMM compared to the DREAMM-2 established 
2.5 mg/kg Q3W dosing regimen. Study details include: 
• 
Study Duration: Approximately 28 months 

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18 
• 
Treatment Duration: Until PD, unacceptable toxicity, or death 
• 
Visit Frequency: Q3W 
Number of Participants: 
Approximately 180 participants will be evaluated in this study, with approximately 
40 participants in treatment Arms A to D and 20 in Arm E. 
Study Treatment Groups and Duration: 
Five treatment arms are planned. Single-agent belantamab mafodotin will be 
administered at doses and schedules as follows: 
• 
Arm A: 2.5 mg/kg Q3W (control; dose reduction to 1.9 mg/kg allowed) 
• 
Arm B: 1.9 mg/kg Q3W (dose reduction to 1.4 mg/kg allowed) 
• 
Arm C: 2.5 mg/kg Q6W (dose reduction to 1.9 mg/kg allowed) 
• 
Arm D: 1.9 mg/kg Q6W (dose reduction to 1.4 mg/kg allowed) 
• 
Arm E: 1.9 mg/kg Q6W with dose modifications based on ocular symptoms 
(patient-reported symptoms using the OSDI), visual acuity assessments (Snellen 
chart or equivalent), and corneal findings (dose reduction to 1.4 mg/kg allowed) 
For Arms A and C, the lowest dose level to be studied in each arm is 1.9 mg/kg and for 
Arms B and D, the lowest dose level to be studied is 1.4 mg/kg (as per dose reduction 
guidelines). 
Participants will be randomized 2:2:2:2:1 into Arms A to E in parallel (at sites 
participating in optional Arm E) or 1:1:1:1 into Arms A to D in parallel (at sites not 
participating in optional Arm E). All participants will be stratified by both the 
International Staging System (ISS) for MM (I vs II vs III) and the number of prior lines 
of anti-myeloma therapy (3 vs 4). Note: For Arm E, in which dose modification 
decisions are informed by the results of the OSDI questionnaire, the OSDI must be 
available in the appropriate language in order for a participant to be randomized into 
this arm. If the OSDI is not available, the participant will be randomized into Arms A to 
D (1:1:1:1). 
The dose of study treatment will be based on actual body weight calculated at baseline 
and may be modified to manage toxicities according to protocol guidelines. 
An interim analysis is planned when approximately 15 participants each in Arms A to D 
have been enrolled and have received 2 doses of study treatment with 1 disease 
assessment following the second dose or confirmed PD per IMWG [Kumar, 2016] or 
death. Any arm in Arms B to D with 2 responders will be discontinued from further 
enrollment and arms with 3 responders will continue enrollment. Enrollment will 
continue as analysis is being performed. If Arm D is stopped due to futility, Arm E will 
also be stopped. If Arms B, C, D, or E are stopped due to futility, participants will be 
given the opportunity to switch to 2.5 mg/kg Q3W (Arm A/control regimen), provided 
the participant has not experienced PD; the data collected from participants after 
switching will not be included in the primary analysis and may be analyzed separately. 

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19 
The end of study is defined when the last patient had their last visit (last subject last dose 
plus 70 days of AE reporting period) or 15 months after last participant first dose 
(LSFD), whichever comes last.  
Following 15 months post-LSFD, DREAMM-14 may move into PACT and/or a managed 
access program/drug supply program, to allow patients who are still receiving benefit 
from belantamab mafodotin to continue receiving treatment. For PACT, the collection of 
new data for all recruited participants who no longer receive study treatment will stop 
entirely and the clinical study database will be closed. A participant is considered to have 
completed the study if they have completed all periods of the study including the last 
visit. Participants in survival follow-up will be considered to have completed the study. 
Those participants still benefiting from study treatment in the opinion of their treating 
physician may continue to receive study treatment in the PACT phase and only serious 
adverse events (SAEs), AEs leading to treatment discontinuation, overdose, pregnancy 
cases, and pre-specified ocular data will be reported directly to GSK. 
Data Monitoring/Other Committee: An Independent Data Monitoring Committee 
(IDMC) consisting of at least 2 physicians and 1 statistician will review safety and 
efficacy data as defined in the IDMC Charter. 

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Protocol Amendment 3 Final  
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1.2. 
Schema 
Figure 1 
DREAMM-14 Study Schema  
 
Abbreviations: BCMA=B-cell maturation antigen; ECOG=Eastern Cooperative Oncology Group; ISS=International Staging System; mAb=monoclonal antibody; MM=multiple myeloma; 
OS=overall survival; PD=progressive disease; PFS=progression-free survival; Q12W=every 12 weeks; Q3W=every 3 weeks; Q6W=every 6 weeks; RRMM=relapsed or refractory 
multiple myeloma. 
* All enrolling study sites will participate in Arms A to D; site participation in Arm E is optional and based on site interest and ability. 
 

CONFIDENTIAL 
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Protocol Amendment 3 Final  
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21 
1.3. 
Schedule of Activities (SoA) 
All assessments planned for participants in Study 209628 are shown in the time and 
events tables as follows: 
• 
Table 1: Screening, On-Treatment, End of Treatment, and Follow-Up Assessments 
• 
Table 2: Additional Assessments for Participants with Hepatitis B Virus 
• 
Table 3: Additional Assessments for Participants with Hepatitis C Virus 
• 
Table 4: Collection Schedule for Pharmacokinetic, Soluble B-Cell Maturation 
Antigen, and Anti-Drug Antibody Samples 
The details of these assessments are provided in footnotes to the tables and further details 
are provided in Section 8. 
All assessments and visits are expected to be conducted in-person at the appropriate study 
site or provider office. However, should the need for decentralized and remote 
assessment approaches arise (e.g., a pandemic) details for implementing these services 
are provided in Section 10.4. 
• 
The timing of planned study assessments may change during the course of the 
study based on emerging data/in-stream data review (e.g., to obtain data closer to 
the time of peak plasma concentrations) to ensure appropriate monitoring. 
• 
Any changes in the timing of time points for any planned study assessments as the 
result of emerging pharmacokinetic/pharmacodynamic data from this study must 
be documented and approved by the relevant study team member and then 
archived in the sponsor and site study files, but will not constitute a protocol 
amendment. 
• 
The competent authority and ethics committee will be informed of any safety 
issues that constitute a substantial amendment and require alteration of the safety 
monitoring scheme or amendment of the Informed Consent Form. The changes 
will be approved by the competent authority and the ethics committee before 
implementation. 

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Protocol Amendment 3 Final  
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22 
Table 1 
Schedule of Activities: Screening, On-Treatment, End of Treatment, and Follow-Up Assessments – ALL ARMS 
• 
All screening assessments must be performed within 28 days before the first dose. 
• 
EOT Visit will either occur within 30 days after last dose or within 30 days of the last Q3W visit, whichever comes last. All EOT visits must occur before the start of any new 
anti-myeloma therapy. AEs and SAEs will be collected up to at least 70 days after the last dose of belantamab mafodotin, either via phone or a follow-up visit. Participants who 
have ocular symptoms at EOT will be followed up for ocular exams (Section 8.3.5) and OSDI questionnaire. After discontinuation of study treatment, the participant should 
continue disease assessments as per the SoA.  Every effort should be made to confirm progressive disease per the IMWG criteria prior to initiating a new anti-myeloma 
therapy.  
• 
PFS Assessments: For participants who discontinue study treatment for a reason other than PD, assessments for PFS will continue to be performed at Q3W (±3 days) from 
the last on-treatment Q3W assessment visit (as shown in the ALL ARMS Q3W regardless of dosing column) until confirmed PD, start of a new anti-myeloma therapy, 
withdrawal of consent, loss to follow-up, end of the study, or death, whichever occurs first. Once a participant experiences PD, move to the OS follow-up schedule. 
• 
OS Follow-Up: All participants who permanently discontinue study treatment and have experienced PD, or have started new anti-myeloma therapy will remain in the study and 
will be followed for survival and subsequent anti-myeloma therapy by chart review, telephone call, or any form of communication Q12W (14 days) from the last Q3W 
assessment visit until withdrawal of consent, loss to follow-up, end of the study, or death, whichever occurs first. A participant does not need to come in for a visit unless they 
are being followed for changes in vision (see Table 8 for exceptions) that are present at EOT. Record the participant’s survival status and whether subsequent anti-myeloma 
therapy was given.  
• 
PACT Phase: Participants who continue to receive study treatment during the PACT phase will be monitored and receive follow-up care in accordance with standard local 
clinical practice. Assessments will revert to the standard of care at a patient’s particular study site and only SAEs, AEs leading to discontinuation of study treatment, overdoses, 
and pregnancy cases [and pre-specified ocular data], will be reported directly to the Sponsor via paper forms (see Section 8.4 and refer to the Study Reference Manual (SRM)). 
For participant discontinuing treatment in the PACT phase, no end of treatment visit is required. 
 
 

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Protocol Amendment 3 Final  
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23 
Time: 
Screening 
(-28 days) 
C1D1 
ALL ARMS 
Q3W 3 days 
regardless of dosing 
(includes PFS 
assessments)  
Arms A & B 
Dosing Visit 
Q3W 3 days 
Arms C, D, & E 
Dosing Visit 
Q6W 3 days 
EOT Visit*  
OS 
Follow-Up 
(Q12W; 
14 days) 
Day (D) 
From D-28 
D1 
D22, D43, etc. 
D22, D43, etc. 
D43, D85 etc. 
 
 
Cycle (C) 
 
C1D1 
 
C2D1, C3D1 etc. 
C2D1, C3D1 etc. 
 
 
Study Assessments 
Informed consent1 
X 
 
 
 
 
 
 
Demographics 
X 
 
 
 
 
 
 
Medical history, disease history, and 
characteristics (includes substance abuse 
and family history of premature 
cardiovascular disease) 
X 
 
 
 
 
 
 
Prior anti-myeloma therapy 
(including radiation and transplants) 
X 
 
 
 
 
 
 
Inclusion/exclusion criteria 
X 
 
 
 
 
 
 
Optional genetics consent2 
X 
 
 
 
 
 
Concomitant medications3 
Ongoing 
 
Safety Assessments 
Physical examination 
X 
X 
 
X4 
X4 
X 
 
Vital signs (BP, HR, and temperature)5 
X 
X 
 
X4 
X4 
X 
 
12-lead ECG6 
X 
 
 
 
 
 
 
ECOG performance status 
X 
X 
X 
 
 
X 
 
Ocular examination7 
X 
 
X8,9 
 
 
X 
X9 
Visual acuity10 
 
Arm E 
only 
 
 
Arm E 
only 
 
 
Hematology11 
X 
X12 
X 
 
 
X 
 
Clinical chemistry11 
X 
X12 
X 
 
 
X 
 
Urinalysis (dipstick) or spot urine (ACR)11, 13 
X 
X12 
Q6W from W7 
 
 
X 
 
eGFR11,14 
X 
X12 
 
X 
X 
X 
 
HBsAg, HBcAb, HCAb, 
HBV DNA, HCV RNA11,15 
X 
 
 
 
 
 
 
Pregnancy test (WOCBP only)11 
X16 
X16 
 
X4, 17 
X4, 17 
X18 
 
AEs/SAEs19 
 
Ongoing 

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Protocol Amendment 3 Final  
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Time: 
Screening 
(-28 days) 
C1D1 
ALL ARMS 
Q3W 3 days 
regardless of dosing 
(includes PFS 
assessments)  
Arms A & B 
Dosing Visit 
Q3W 3 days 
Arms C, D, & E 
Dosing Visit 
Q6W 3 days 
EOT Visit*  
OS 
Follow-Up 
(Q12W; 
14 days) 
Day (D) 
From D-28 
D1 
D22, D43, etc. 
D22, D43, etc. 
D43, D85 etc. 
 
 
Cycle (C) 
 
C1D1 
 
C2D1, C3D1 etc. 
C2D1, C3D1 etc. 
 
 
Disease Evaluation Assessments: 20 For participants who are discontinuing study treatment due to PD, confirmation based on laboratory assessments must be performed from a 
different sample collection (serum/urine) preferably before institution of any new anti-myeloma therapy and, if possible, within 14 days of the date of the initial assessment showing 
unconfirmed progressive disease.  
2 microglobulin11 
X 
 
 
 
 
 
 
UPEP (on 24 h urine collection)11 
X 
X12 
X 
 
 
X 
 
Urine immunofixation11 
X 
 
X21 
 
 
X21 
 
SPEP11 
X 
X12 
X 
 
 
X 
 
Serum immunofixation11 
X 
 
X21 
 
 
X21 
 
Serum kappa, lambda FLC, FLC ratio11 
X 
X12 
X 
 
 
X 
 
IgG, IgM, IgA11 
X 
 
X 
 
 
X 
 
IgD/E, if applicable11, 22 
X 
 
X 
 
 
X 
 
Calcium corrected for albumin (serum)11 
X 
 
X 
 
 
X 
 
Response assessment23 
 
 
X 
 
 
X 
 
BM Aspirate/Biopsy Assessments11 
BM (biopsy and/or aspirate) for disease 
assessment (percentage of malignant 
plasma cells) 
X24 
 
X25 
 
 
 
 
BM aspirate for FISH testing26 
 
 
 
 
 
 
BM (biopsy and/or aspirate) for BCMA 
expression and biomarker research27 
 
 
 
 
 
 
BM biopsy to assess sCR by IHC 
 
 
X28 
 
 
 
 
Imaging Assessments 
Skeletal survey29 
X 
 
As clinically indicated30 
 
 
EMD assessment31 
X 
 
X (Q12W) 
 
 
X 
 
Study Treatment 
Premedication (as needed) 
 
X 
 
X 
X 
 
 
Belantamab mafodotin 
 
X 
 
X32 
X32 
 
 

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209628 
 
 
Protocol Amendment 3 Final  
25 Jun 2024 
25 
Time: 
Screening 
(-28 days) 
C1D1 
ALL ARMS 
Q3W 3 days 
regardless of dosing 
(includes PFS 
assessments)  
Arms A & B 
Dosing Visit 
Q3W 3 days 
Arms C, D, & E 
Dosing Visit 
Q6W 3 days 
EOT Visit*  
OS 
Follow-Up 
(Q12W; 
14 days) 
Day (D) 
From D-28 
D1 
D22, D43, etc. 
D22, D43, etc. 
D43, D85 etc. 
 
 
Cycle (C) 
 
C1D1 
 
C2D1, C3D1 etc. 
C2D1, C3D1 etc. 
 
 
Supportive Care 
Cooling eye masks33 
 
X 
 
X 
X 
 
 
Preservative-free artificial tears33 
 
X 
Daily until EOT 
 
 
 
 
PK and ADA Assessments11 
PK34 
 
X 
 
X4 
X4 
 
 
Immunogenicity (ADA)35 
 
X 
 
X4 
X4 
 
 
Biomarker Assessments11 
sBCMA (serum)36 
 
X 
 
X4 
X4 
 
 
TBNK panel (whole blood)37 
 
X 
X 
 
 
 
 
Health Outcomes Assessments 
PRO-CTCAE 
 
X 
X38 
 
 
X 
 
OSDI39 
 
X 
X40 
 
 
X40 
X40 
FACT-GP5 
 
X 
X38 
 
 
X 
 
EORTC-QLQ-C30 
 
X 
X38 
 
 
X 
 
EORTC-QLQ-MY20 
 
X 
X38 
 
 
X 
 
PGIS41 
 
X 
Q6W 
 
 
X 
 
PGIC41 
 
 
Q6W 
 
 
X 
 
Post-PD Status 
Survival status42 
 
 
 
 
 
 
X 
Subsequent anti-myeloma therapy43 
 
 
 
 
 
X 
X 
Abbreviations: ACR=albumin/creatinine ratio; ADA=anti-drug antibody; AE=adverse event; AESI=adverse event of special interest; BCMA=B-cell maturation antigen; BM=bone marrow; 
BP=blood pressure; C=Cycle; CR=complete response; CT=computed tomography; D=Day; DNA=deoxyribonucleic acid; ECG=electrocardiogram; ECOG=Eastern Cooperative 
Oncology Group; eGFR=estimated glomerular filtration rate; EMD=extramedullary disease; EOI=end of infusion; EORTC-QLQ-C30=European Organisation for Research and 
Treatment of Cancer Quality of Life Questionnaire 30-item Core Module; EORTC-QLQ-MY20=European Organisation for Research and Treatment of Cancer Quality of Life 
Questionnaire 20-item Multiple Myeloma Module; EOT=end of treatment; FACT-GP5=Functional Assessment of Cancer Therapy – General Population; FISH=florescence in-situ 
hybridization; FLC=free light chain; FSH=follicle-stimulating hormone; HBcAb=hepatitis B core antibody; HBsAg=hepatitis B surface antigen; HBV=hepatitis B virus; HCAb; 
hepatitis C antibody HCV=hepatitis C virus; HR=heart rate; ICF=Informed Consent Form; Ig=immunoglobulin; IHC=immunohistochemistry; IMWG=International Myeloma Working 

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Protocol Amendment 3 Final  
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26 
Group; MDRD=Modified Diet in Renal Disease; MRI=magnetic resonance imaging; OS=overall survival; OSDI=Ocular Surface Disease Index; PD=progressive disease; 
PET=positron emission tomography; PFS=progression-free survival; PGIC=Patient Global Impression of Change; PGIS=Patient Global Impression of Severity; 
PK=pharmacokinetics; PRO-CTCAE=Patient-Reported Outcomes Version of the Common Terminology Criteria for Adverse Events; Q12W=every 12 weeks; Q3W=every 3 weeks; 
Q6W=every 6 weeks; QTcF=QT interval corrected using Fridericia’s formula; RNA=ribonucleic acid; SAE=serious adverse event; sBCMA=soluble B-cell maturation antigen; 
sCR=stringent complete response; SOI=start of infusion; SPD=sum of the products of the perpendicular diameters; SPEP=serum protein electrophoresis; SRM=Study Reference 
Manual; TBNK=T, B, and natural killer cells; UPEP=urine protein electrophoresis; US=United States; W=week; WOCBP=women of childbearing potential; WONCBP=women of 
nonchildbearing potential. 
*  
EOT Visit will either occur within 30 days after last dose or within 30 days of the last Q3W visit, whichever comes last. All EOT visits must occur before the start of any new 
anti-myeloma therapy. 
1. 
The ICF must be signed before any study-specific assessments are performed. 
2. 
Informed consent for optional genetics research must be obtained before collecting the sample. The sample will be collected at the first opportunity after a participant has met all 
eligibility requirements or on C1D1 before infusion. 
3. 
Concomitant medications administered after EOT should only be recorded for SAEs/AESIs as defined in Section 8.4. 
4. 
If no treatment is administered at C2 or later cycles, the following assessments do not need to be done, unless clinically indicated or at EOT visit: physical examination, vital signs, 
and pregnancy test. For dose-related time points (up to C12D1), if a participant is not dosed do not collect associated PK, ADA, and sBCMA samples.In the case of liver events, 
PK and sBCMA samples must be collected. 
5. 
On C1D1 (first infusion) dosing day, vital signs must be assessed at pre-dose (within 30 minutes before the SOI), within 15 minutes after EOI, and 1 hour post-EOI. On 
subsequent dosing days, vital signs must be assessed at pre-dose (within 30 minutes before the SOI) and within 15 minutes after EOI. On days where vital sign time points align 
with blood sampling time points, vital signs should be assessed before blood samples are drawn. On days where vital signs are measured multiple times, temperature does not 
need to be repeated unless clinically indicated. 
6. 
Single ECG at screening, unless QTcF is prolonged, in which case triplicate ECGs are required; to be performed after at least 5 minutes of rest. 
7. 
See Section 8.3.5.1 for list of ocular examination procedures. All ocular examinations will be performed by a qualified eye care specialist such as an ophthalmologist or optometrist 
(Section 10.1).  
8. 
On-treatment ocular examinations should occur Q3W irrespective of dosing. When dosing, ocular examinations must be performed within 5 days before dosing. If the participant is 
not being dosed, ocular examinations may be performed within 3 days of the Q3W visit. If a participant develops vision changes or other ocular symptoms, the participant should 
be promptly evaluated by a qualified eye care specialist such as an ophthalmologist or optometrist (as defined in Section 10.1). In case of persistent ocular examination findings, 
newly developed ocular symptoms, or vision changes, the participants will have further exams until resolution (to Grade 1 or baseline), or more frequently as clinically indicated by 
the qualified eye care specialist such as an ophthalmologist or optometrist. 
9. 
Participants with corneal events (KVA Grade 2 or higher) at EOT will be followed by a qualified eyecare specialist until full resolution of ophthalmic changes (KVA Grade 1 or 
better), start of new anti‑myeloma therapy or up to 1 year, whichever occurs first. If the participant is in PFS follow-up, ocular assessments must be performed Q3W ±3 days. If the 
participant is in OS follow-up, ocular assessments must be performed Q12W ±14 days. Additional ocular examinations can be performed at the discretion of the eye care 
specialist and/or investigator.  
10. For participants in Arm E only, visual acuity will be assessed at the oncologist’s office before dosing. 
11. See Section 10.13 for a comprehensive list of laboratory tests that must be collected for all participants and if analyzed locally or centrally.  
12. Assessment does not need to be repeated on C1D1 if corresponding screening assessment was completed within 72 hours before the first dose. Thereafter, hematology and 
clinical chemistry should be performed and reviewed within 72 hours prior to dosing. 

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13. ACR (spot urine preferably from first void). Urine dipstick for protein may be used to assess for presence of urine protein. ACR must be collected at screening and thereafter to be 
done in any participant with urine dipstick result of ≥2+ (during study treatment), or with positive protein if urine dipstick protein quantification is not available. ACR will be 
performed at a local laboratory. If local testing is not available, then central testing will be performed.  
14. eGFR as calculated by MDRD formula (see Section 10.5). 
15. See eligibility criteria (Section 5). HBV DNA testing must be done to determine participant eligibility only if HBsAg+ or HBcAb+. HCV RNA testing must be done to determine 
participant eligibility only if HCAb+. 
16. Serum testing at screening and C1D1. The first test should be performed within 10 to 14 days before the first dose and the second test should be performed within 24 hours before 
the first dose. For questionable cases (child-bearing status), FSH and estradiol (as needed in WONCPB potential only) should be performed at local laboratory (see Section 8.3.7). 
17. CXD1 pregnancy tests may be either serum or urine and each pregnancy test must be performed within 72 hours before dosing. 
18. Final pregnancy test (serum or urine) must be performed in WOCBP within 70 days after the last dose. Follow-up pregnancy assessment by telephone for WOCBP should be 
performed 4 months after the last dose of study treatment. 
19. AEs/SAEs will be collected up to at least 70 days after the last dose of study treatment. All SAEs related to study participation (e.g., protocol-mandated procedures, tests, or 
change in existing therapy) are to be collected from consent through OS follow-up. All AEs/SAEs will be followed until the event is resolved, stabilized, otherwise explained, or the 
participant is lost to follow-up (see Section 8.4).  
20. Disease evaluation (except imaging and skeletal survey) will be performed Q3W (± 3 days) even if treatment is not administered. For participants who are discontinuing study 
treatment due to PD, the confirmation of PD is based on two central laboratory assessments performed from a different sample collection performed either on the same day or, if 
possible, within 14 days of the original date of PD, preferably before institution of any new anti-myeloma therapy. This may be performed at the EOT visit. 
21. Serum/urine immunofixation will be performed each time that M protein is not quantifiable by SPEP (0 g/dL) or UPEP (0 mg/24hr).  
22. Only required for participants with IgD/E myeloma. 
23. To be assessed based on disease laboratory tests and imaging (if applicable) as outlined in this table. Response assessment is based on IMWG criteria [Kumar, 2016]. 
24. Portion of the aspirate collected for disease assessment will be used for FISH testing. Any remaining biopsy and/or aspirate sample from disease assessments (depending on 
institutional practice) should be retained for biomarker research. 
25. For flow cytometry or IHC analysis at the time of suspected CR for confirmation of plasma cells <5% (always) or at time of suspected PD (only if not evident otherwise). BM must 
be collected as per institutional practice; however, a BM core biopsy is preferred. To be tested locally. 
26. FISH testing to be performed locally at least for: t(4;14), t(14;16), amp(1q), del(1p), and del(17p13). If participant is known to have tested positive for t(4;14) or t(14/16),on previous 
tests, FISH for those translocations does not need to be repeated, regardless of when the previous tests were performed. For amp(1q), del(1p), and del(17p13), FISH results from 
samples taken within 60 days before the first dose are acceptable. The results of this test are not required for participants to start D1. If testing cannot be performed at a local 
laboratory the samples can be sent to the central laboratory. 
27. BM collection should be performed per institutional practice. 
28. In participants achieving a CR, BM biopsy to confirm sCR by IHC (kappa/lambda ratio). This will be collected for all participants and should be analyzed locally (if not available, 
central testing can be used). 
29. Imaging of bones for lytic lesions by a method aligned with the institutional guidance (e.g., X-ray, CT, or MRI). The same modality used at screening must be used throughout 
study. 
30. Only if clinically indicated or if worsening clinical symptoms suggest skeletal PD. Imaging is not required if the PD is evident otherwise. The same modality used at screening must 
be used throughout study. Imaging of bones for lytic lesions by a method aligned with the institutional guidance (e.g., X-ray, CT, or MRI). 
31. Imaging (i.e., CT, MRI, or PET-CT) is only required for participants with EMD, per local guidance, Q12W 1 week from the date of randomization (e.g., W13, W25, W37, etc.) 
through 1 year and then as clinically indicated. The same modality used at screening must be used throughout the study. Selected target lesion must be measured and followed 

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over time. Plasmacytoma measurements should be taken from the CT portion of the PET-CT, or MRI scans, or dedicated CT scans, where applicable. For participants with only 
skin involvement, skin lesions should be measured with a ruler. Measurement of tumor burden will be determined by the SPD of the measured lesions. All imaging scans must be 
retained at the investigative site as source documents. See Section 8.2 for more information on imaging, EMD measurement and follow-up, and PD due to EMD. Also see the 
SRM for additional information. 
32. Belantamab mafodotin administration on D1 of C2 to CX, ±3 days. All scheduled cycle visits must be calculated from C1D1. See Section 6.1.1 for dosing schedule for Arms A to E 
and Section 6.5 in case a dose is delayed. 
33. Cooling eye masks may be applied to both eyes for as long as tolerated, up to 4 hours. Preservative-free artificial tears should be used 4 to 8 times a day in each eye, beginning 
from C1D1 until EOT. Allow 5 to 10 minutes between administration of artificial tears and steroid eye drops, if administered together. In the event of ocular symptoms (i.e., dry 
eyes), the use of artificial tears may be increased up to every 2 hours. See Section 6.8.1 for more detail on supportive care information. 
34. PK samples are required for all participants according to the schedules for PK sample collection in each treatment arm (Table 4). 
35. Blood samples for ADA measurement in serum will be collected before the start of the infusion on dosing days at selected doses in each treatment arm (Table 4). 
36. sBCMA (serum): Collect sBCMA samples at the same PK time points as specified in Table 4. 
37. TBNK samples to be collected pre-dose on C1D1. All other timepoints, samples may be collected at any time during Q3W assessment. 
38. Collected only while a participant remains on treatment. 
39. Collected for all participants in all arms. For Arm E only: OSDI will contribute to determination of dose modification decisions (Go/No-Go) for participants (see Section 6.5). 
40. Participants with no corneal events at the EOT ocular assessment will have no further OSDI collection. Participants with corneal events (see Table 8 for exceptions) at the EOT 
ocular assessment will have OSDI collected Q12W until resolution or baseline, with the final OSDI collected at the Q12W visit after resolution or return to baseline, or for up to 
12 months, whichever occurs first. 
41. Complete every 6 weeks from W7 (W7, W13, W19, W25, etc.) during treatment and at EOT. PGIC is not administered at C1D1. 
42. Survival status may be obtained via a telephone call. 
43. Information on subsequent anti-myeloma therapies and response to these therapies to be collected at any time after EOT visit. 

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Table 2 
Additional Assessments for Participants with HBV 
Note: The assessments listed in this table apply only to participants (those in screening and those already enrolled) who have a history of HBV; all assessments 
must be done as needed in addition to the required assessments for all participants listed in Table 1. 
HBV Assessments 
During Screening/ 
Before Starting Treatment 
During Treatment 
EOT 
HBV-related liver imaging1 
X 
X 
X 
HBV DNA testing2 
X 
X 
X 
Prevention of HBV reactivation3 
X 
X 
X 
Abbreviations: DNA=deoxyribonucleic acid; EOT=end of treatment; HBsAg=hepatitis B surface antigen; HBV=hepatitis B virus; LFT=liver function test. 
1. 
For participants who test positive for HBsAg, conduct liver imaging (specific test per standard of care at local institution) to rule out/identify cirrhosis, focal hepatic lesions, and/or 
biliary abnormalities at baseline. Repeat liver imaging 1 year after starting treatment with belantamab mafodotin and twice yearly thereafter for as long as a participant remains on 
study treatment or as clinically indicated. 
2. 
Conduct HBV DNA testing before the start of treatment with belantamab mafodotin and every 12 weeks thereafter, if LFT elevations that fulfill liver event monitoring or stopping 
criteria (Section 7.1.1 and Section 10.6) occur, or if there is any clinical suspicion of hepatitis reactivation. 
3. 
For participants who test positive for HBsAg, appropriate antiviral therapy (e.g., tenofovir or entecavir) per local guidance should be started before beginning treatment with 
belantamab mafodotin, continue through to completion of treatment with belantamab mafodotin, and should not be stopped unless advised by a local hepatology or virology 
services. 
Table 3 
Additional Assessments for Participants with HCV 
Note: The assessments listed in this table apply only to participants (those in screening and those already enrolled) who have a history of HCV; all assessments 
must be done as needed in addition to the required assessments for all participants listed in Table 1. 
HCV Assessments 
During Screening/ 
Before Starting Treatment 
During Treatment 
After Treatment 
HCV RNA testing1 
X 
X 
 
Therapy for active HCV2 
X 
 
 
Abbreviations: HCV=hepatitis C virus; LFT=liver function test; RNA=ribonucleic acid. 
1. 
Conduct HCV RNA testing before the start of treatment with belantamab mafodotin and every 12 weeks thereafter, if LFT elevations that fulfill liver event monitoring or stopping 
criteria (Section 7.1.1 and Section 10.6) occur, or if there is any clinical suspicion of hepatitis reactivation. 
2. 
Antiviral therapy should be given to participants with HCV before enrollment using an 8 (to 12) week course with curative intent per local guidance. Before enrollment, participants 
must have a negative HCV RNA test result after a washout period of 4 weeks after antiviral therapy. 

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Table 4 
Collection Schedule for PK, sBCMA, and ADA Samples – ALL ARMS 
Dose Number/Visit 
Day 
Arm A: 2.5 mg/kg Q3W 
Arm B: 1.9 mg/kg Q3W 
Arm C: 2.5 mg/kg Q6W 
Arm D: 1.9 mg/kg Q6W 
Arm E: 1.9 mg/kg Q6W (symptom-based 
dose modification) 
Window 
PK1 
sBCMA2 
ADA3 
PK1 
sBCMA2 
ADA3 
1 
1 
Pre-dose 
Pre-dose 
Pre-dose 
Pre-dose 
Pre-dose 
Pre-dose 
Within 0-30 mins prior to SOI 
EOI 
EOI 
 
EOI 
EOI 
 
Within 0-30 mins after EOI 
SOI + 2 h 
SOI + 2 h 
 
SOI + 2 h 
SOI + 2 h 
 
Within ±15 minutes 
2 
SOI + 24 h 
SOI + 24 h 
 
SOI + 24 h 
SOI + 24 h 
 
Within ±2 hours 
4 
Anytime 
Anytime 
 
Anytime 
Anytime 
 
Within ±24 hours 
8-15 
Anytime 
Anytime 
 
Anytime 
Anytime 
 
1 sample anytime between Day 
8-15 in the cycle, inclusive. 
22 
If next dose 
delayed 
If next dose 
delayed 
 
Anytime 
Anytime 
 
Within 72 hours 
43 
 
 
 
If next dose 
delayed 
If next dose 
delayed 
 
Within 72 hours 
2 
1 
Pre-dose 
Pre-dose 
Pre-dose 
Pre-dose 
Pre-dose 
Pre-dose 
Within 0-30 mins prior to SOI 
EOI 
EOI 
 
EOI 
EOI 
 
Within 0-30 mins after EOI 
3 
1 
Pre-dose 
Pre-dose 
Pre-dose 
Pre-dose 
Pre-dose 
Pre-dose 
Within 0-30 mins prior to SOI 
EOI 
EOI 
 
EOI 
EOI 
 
Within 0-30 mins after EOI 
4 
1 
Pre-dose 
Pre-dose 
 
Pre-dose 
Pre-dose 
 
Within 0-30 mins prior to SOI 
6 
1 
Pre-dose 
Pre-dose 
Pre-dose 
Pre-dose 
Pre-dose 
Pre-dose 
9 
1 
Pre-dose 
Pre-dose 
Pre-dose 
Pre-dose 
Pre-dose 
Pre-dose 
12  
1 
Pre-dose 
Pre-dose 
Pre-dose 
Pre-dose 
Pre-dose 
Pre-dose 
Abbreviations: ADA=anti-drug antibody; AE=adverse event; cys-mcMMAF=cysteine-maleimidocaproyl monomethyl auristatin F; EOI=end of infusion; EOT=end of treatment; 
mAb=monoclonal antibody; PK=pharmacokinetics; Q3W=every 3 weeks; Q6W=every 6 weeks; sBCMA=soluble B-cell maturation antigen; SOI=start of infusion. 
1. 
Plasma sample for belantamab mafodotin and cys-mcMMAF at each time point 
2. 
Serum sample for sBCMA at each time point 
Serum sample for ADA at each time point 

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2. 
INTRODUCTION 
2.1. 
Study Rationale 
Belantamab mafodotin (GSK2857916) is a B-cell maturation antigen (BCMA)-directed 
antibody-drug conjugate (ADC) that is conjugated to a microtubule disrupting agent, 
monomethyl auristatin F (MMAF) with antitumor activity in multiple myeloma (MM) 
cells. Belantamab mafodotin mediates the killing of tumor cells through MMAF-induced 
apoptosis as well as by tumor cell lysis through antibody-dependent cellular cytotoxicity 
(ADCC) and antibody-dependent cellular phagocytosis (ADCP). Clinically, single-agent 
belantamab mafodotin has demonstrated efficacy in participants with relapsed or 
refractory multiple myeloma (RRMM) who have received at least 4 prior therapies, 
including an anti-CD38 monoclonal antibody, a proteasome inhibitor, and an 
immunomodulatory agent.  
Efficacy has been demonstrated at 2.5 mg/kg dose of belantamab mafodotin , 
administered as an IV infusion once every 3 weeks (Q3W) until progressive disease (PD) 
or unacceptable toxicity. The Phase 2, open-label, randomized study investigating the 
efficacy and safety of belantamab mafodotin in participants with RRMM (DREAMM-2) 
[Lonial, 2020] met its primary endpoint for overall response rate (ORR) of 31% (n=97, 
97.5% confidence interval [CI]: 20.8%, 42.6%). DREAMM-2 patient-reported outcomes 
(PROs) demonstrated that participants treated with belantamab mafodotin at the dose of 
2.5 mg/kg generally maintained their health-related quality of life (HRQoL) and physical 
functioning while on treatment. Although vision-related activities can be limited during 
episodes of clinically significant ocular PRO changes, these changes are temporary and 
do not adversely impact overall HRQoL and physical functioning [Popat, 2020]. 
Although belantamab mafodotin has demonstrated efficacy in this population, ocular 
toxicity is common and expected, having been reported in other MMAF-containing 
ADCs [Parrozzani, 2020]. Belantamab mafodotin administered at the dose of 2.5 mg/kg 
Q3W can cause changes in the corneal epithelium resulting in changes in vision. 
Keratopathy (defined as corneal examination findings of microcyst-like keratopathy, 
which were mapped to the preferred term keratopathy per Medical Dictionary for 
Regulatory Activities [MedDRA]) was the most frequent ocular AE in the 
DREAMM-2 study (71% of participants, with 44% Grade 3 and 1% Grade 4) 
[Lonial, 2020]. The corneal changes often result in visual acuity changes, with 54% [51 
out of 95] of participants experiencing best corrected visual acuity (BCVA) changes of 
any grade and 31% [29 out of 95] of Grade 3 to 4 [Farooq, 2020]. These ocular toxicities 
resulted in high rates of dose delays (47% [45 out of 95] dose delays due to keratopathy) 
and dose reductions (23% [22 out of 95] dose reductions due to keratopathy). 
Alternative dosing regimens of single-agent belantamab mafodotin will be explored in 
Study 209628 to determine if an improved overall benefit/risk profile can be achieved by 
modifying the belantamab mafodotin dose, schedule, or both. 

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In addition to investigating alternative dosing schedules to mitigate the risk of ocular 
toxicity (Arms A to D), Study 209628 will also assess the use of ocular symptoms 
(patient-reported symptoms using the Ocular Surface Disease Index [OSDI]) and visual 
acuity assessments (Snellen chart or equivalent) to inform dose modification decisions 
and assess potential impact on the frequency of ocular examinations conducted by an eye 
care specialist on safety and efficacy for the participant (Arm E). 
2.2. 
Background 
2.2.1. 
Multiple Myeloma 
MM is an incurable malignancy and accounts for 1% of all cancers and for 10% of all 
hematologic malignancies [Moreau, 2017]. Worldwide, approximately 103,000 new 
cases are diagnosed annually, and an estimated 32,270 new cases and 12,830 deaths will 
have occurred in the US in 2020 Siegel, 2020]. 
Treatment of symptomatic or active MM includes autologous stem cell transplant and 
different combinations of drugs having different mechanisms of action: corticosteroids, 
alkylating agents (e.g., melphalan, cyclophosphamide), anthracyclines, proteasome 
inhibitors (e.g., bortezomib, carfilzomib, ixazomib), histone deacetylase inhibitors (e.g., 
panobinostat), immunomodulatory drugs (e.g., thalidomide, lenalidomide, 
pomalidomide), nuclear export inhibitors (e.g., selinexor) and monoclonal antibodies 
(mAbs) (e.g., daratumumab, isatuximab, elotuzumab) [Pinto, 2020; Rajkumar, 2020]. 
Although almost 100% of patients will respond to first-line therapy, most of them will 
experience eventual PD and require further treatment. Duration of response (DoR) and 
response rates decline dramatically in every subsequent line of therapy for this 
malignancy. In addition, despite significant advances in these treatment options, most 
patients with MM will ultimately develop resistance to existing therapies and die of 
relapse. Therefore, there is a high unmet medical need for new treatment options that can 
help improve clinical outcomes and overcome resistance to existing drugs for patients 
with MM who have progressed on existing therapies. 
2.2.2. 
Antibody-Drug Conjugate Belantamab Mafodotin 
Belantamab mafodotin binds to BCMA and kills MM cells via a multi-modal mechanism 
including release of cytotoxic cysteine-maleimidocaproyl monomethyl auristatin F 
(cys-mcMMAF) inside BCMA-expressing MM cells, thereby inducing apoptosis, 
enhancing ADCC and ADCP, and inducing immunogenic cell death (Figure 2) 
[Oca, 2019; Tai, 2014]. Exposure of dendritic cells to tumor cells undergoing 
immunogenic cell death is expected to result in an antigen-specific T-cell response, 
enhancing the immunogenic response against MM. 

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Figure 2 
Belantamab Mafodotin Mechanism of Action 
 
Abbreviations: ADC=antibody-drug conjugate; ADCC/ADCP=antibody-dependent cell-mediated cytotoxicity/antibody-
dependent cellular phagocytosis; BCMA=B-cell maturation antigen. 
2.2.3. 
Clinical Experience with Belantamab Mafodotin relevant for 
DREAMM-14 
2.2.3.1. 
Clinical Studies 
Single-agent belantamab mafodotin has demonstrated positive clinical activity with a 
well-defined and manageable safety profile in heavily pre-treated participants with 
RRMM (Q3W schedule via IV administration) in the first time in human (FTIH) study 
BMA117159 (DREAMM-1; NCT02064387) and the pivotal Phase 1 Study 205678 
(DREAMM-2; NCT03525678). 
FTIH Study BMA117159/DREAMM-1 
In the FTIH DREAMM-1 study, which consisted of a dose escalation period (Part 1, 
n=38) and a dose expansion period (Part 2, n=35), as of the primary analysis data cutoff 
date of 31 August 2018, a total of 73 participants with RRMM received at least 1 dose of 
belantamab mafodotin [Trudel, 2019] (see also the current version of the Belantamab 
Mafodotin Investigator’s Brochure). 
As of the efficacy data cutoff date of 31 August 2018, a total of 35 participants were 
treated at the 3.4 mg/kg dose in Part 2 of the DREAMM-1 study. Participants were 
heavily pre-treated: 57% of participants had 5 or more prior lines of therapy. The ORR 
was 60% (95% CI: 42.1%, 76.1%) and was comprised of partial response (PR): 6%; very 
good partial response (VGPR): 40%; complete response (CR): 9%; and stringent 
complete response (sCR): 6%. The median DoR was 14.3 months (95% CI: 10.6 months, 
not reached [NR]). The median progression-free survival (PFS) in this population was 
12.0 months (95% CI: 3.1 months, not estimable [NE]). For participants with prior 

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daratumumab treatment and refractory to both immunomodulatory drugs and proteasome 
inhibitors (n=5/13), the confirmed ORR was 39% (95% CI: 13.9%, 68.4%) and median 
PFS was 6.2 months (95% CI: 0.7 months, 7.9 months) [Trudel, 2019]. 
Phase 2 Study 205678/DREAMM-2 
The Phase 2 Study 205678/DREAMM-2 evaluated the same 2 single-agent IV doses (2.5 
and 3.4 mg/kg) of belantamab mafodotin administered Q3W until PD in participants who 
have failed at least 3 prior lines of anti-myeloma therapy, including an anti-CD38 
antibody, and who are refractory to an immunomodulatory drug and a proteasome 
inhibitor. A total of 194 participants received frozen drug product in the main cohort and 
24 participants received 3.4 mg/kg lyophilized drug product. Primary analysis data from 
this study indicated no new safety signals and the profile of AEs was similar to the 
experience in the DREAMM-1 study for both arms. Both dose levels, 2.5 and 3.4 mg/kg, 
were shown to have a positive benefit/risk profile [Li, 2017; Lonial, 2020]. 
The final analysis of the study (data cut-off date: 31-Mar-2022) confirmed the efficacy 
and safety results of the primary analysis. The ORR was 32% (97.5% CI: 21.7,43.6) in 
the 2.5 mg/kg cohort and 35% (97.5% CI: 24.8, 47.0) in the 3.4 mg/kg cohort. More than 
half of responders (58% and 69%) had a response of VGPR or better. The median DoR 
was 12.5 months (95% CI: 4.2, 19.3) in the 2.5 mg/kg cohort and 6.2 months (95% CI: 
4.8,18.7) at 3.4 mg/kg cohort. The median PFS was 2.8 months (95% CI: 1.6, 3.6) and 
3.9 months (95% CI: 2.0, 5.8), respectively. The median OS was 15.3 months (95% CI: 
9.9, 18.9) in the 2.5 mg/kg cohort and 14.0 months (95% CI: 10.0, 18.1) in the 3.4 mg/kg 
cohort. 
Key safety data of the DREAMM-2 study include the following (data for 2.5 mg/kg 
cohort are presented first, followed by the 3.4 mg/kg cohort): Serious adverse events 
(SAE) occurred in 45% and 54% of participants, of which 15% and 21% were related to 
study treatment. SAE in >3% of participants in either cohort included pneumonia (7% 
and 14%), pyrexia (7% and 5%), and hypercalcemia (4% and none). Fatal SAEs related 
to study treatment occurred in 1% and 2% of participants, including sepsis (1%), cardiac 
arrest (1%), and lung infection (1%). Grade 3 or 4 AEs related to study treatment were 
reported in 58% and 64% of the participants. The most common treatment-related Grade 
2 AEs reported were keratopathy (59% and 64%), thrombocytopenia (14% and 27%), 
vision blurred (13% and 18%), infusion-related reaction (13% and 5%), anemia (6% and 
10%), and neutropenia (4% and 10%). The most common AEs (≥25%) were keratopathy, 
thrombocytopenia, anemia, nausea, vision blurred, and pyrexia. Infusion-related reactions 
of any Grade occurred in 21% and 16% of participants, including Grade 3 in 3% and 1%. 
Permanent discontinuation due to AEs occurred in 12% of participants in both cohorts of 
which 9% and 5% were considered treatment-related. Keratopathy (3% in both cohorts) 
was the most frequent AE resulting in permanent discontinuation. Dose interruptions due 
to an AE occurred in 54% and 62% of participants. Dose reductions due to an AE 
occurred in 36% and 44% of participants. AEs which required a dose reduction in >3% of 
patients included keratopathy (28% and 30%) and thrombocytopenia (4% and 11%). The 
most common Grade 3 or 4 (≥10%) laboratory abnormalities were decreases of 

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lymphocytes, platelet count, hemoglobin, neutrophils, and leukocytes, and increases in 
gamma glutamyl transferase values. 
2.2.3.2. 
Safety 
Single-agent belantamab mafodotin was demonstrated to have a manageable safety 
profile in heavily pre-treated participants with RRMM. Safety data for single-agent 
belantamab mafodotin were pooled (data as of 20 September 2019) for the DREAMM-2 
study and supportive FTIH study DREAMM-1 by treatment cohorts of 2.5 mg/kg and 
3.4 mg/kg. 
The most common AEs in both treatment cohorts were keratopathy (corneal epithelium 
changes observed on ophthalmic examination), thrombocytopenia, and anemia. The 
incidence of AEs, including Grade 3 to 4 AEs was comparable between belantamab 
mafodotin 2.5 mg/kg and 3.4 mg/kg cohorts. AEs leading to dose delays and dose 
reductions were less frequent in the 2.5 mg/kg cohort compared to the 3.4 mg/kg cohort 
(51% and 32% compared to 67% and 52%, respectively). AEs leading to permanent 
treatment discontinuation occurred in 10% and 11% of participants in the 2.5 and 
3.4 mg/kg cohorts, respectively. More participants in the 3.4 mg/kg cohort experienced 
serious adverse events (SAEs) (50%) and fatal SAEs (6%) compared with the 2.5 mg/kg 
cohort (41% and 3%, respectively). 
Single-agent belantamab mafodotin 2.5 mg/kg was selected as the recommended dose 
based on comparable efficacy with a more favorable safety profile (i.e., lower incidence 
of thrombocytopenia and neutropenia and less frequent dose delays or reductions) 
compared with the 3.4 mg/kg dose. 
Adverse Events of Special Interest 
Adverse events of special interest (AESIs) for belantamab mafodotin are corneal events, 
thrombocytopenia, and infusion-related reactions (IRRs), and are described as follows. 
Corneal Events 
Corneal events, reported in most cases as keratopathy, blurred vision, and dry eye events, 
are the most frequently reported AEs with belantamab mafodotin. 
In the DREAMM-2 final analysis report (data as of 31 March 2022), events in the Eye 
disorders System Organ Class occurred in 98% of participants treated with belantamab 
mafodotin 2.5 mg/kg (n=95). The most common ocular AEs were keratopathy (changes 
in corneal epithelium identified on eye exam, with or without symptoms, 71%), blurred 
vision (23%), and dry eye (15%). Belantamab mafodotin can cause keratopathy with or 
without vision impairment. In the safety population treated with belantamab mafodotin 
2.5 mg/kg (n=95), median time to onset for the first occurrence of a keratopathy event 
was 28 days. 
Dose modifications, specifically dose delays, appear to be the most important mitigation 
strategy. Concomitant use of preservative-free artificial tear drops might also be 
beneficial, although they are not expected to prevent the occurrence of the epitheliopathy. 

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Participants with a history of dry eye symptoms prior to starting belantamab mafodotin 
were more likely to develop keratopathy compared with participants without such history. 
Therefore, active management of dry eye symptoms prior to and during treatment is 
recommended (i.e., administration of preservative-free artificial tears). Permanent 
treatment discontinuations due to corneal events were rare and occurred in <5% of 
participants. 
The ocular sub-study of DREAMM-2 provided no evidence that corticosteroid eye drops 
are beneficial in preventing or mitigating corneal events. 
Thrombocytopenia 
In the DREAMM-2 final analysis report (data as of 31 March 2022), thrombocytopenic 
events (thrombocytopenia and platelet count decreased) occurred in 38% participants 
treated with belantamab mafodotin 2.5 mg/kg; severity ranging between Grade 1 and 4. 
Grade 3 or higher events occurred in 22% of participants, and 1% overall were 
considered SAEs. The median time-to-onset of the first thrombocytopenic event was 25.5 
days and the median time to resolution was 21.5 days. 
Most participants had a decrease from baseline in their platelet counts during the study. 
In general, participants who initiated treatment with lower platelet numbers tended to 
continue to have thrombocytopenia while on treatment with belantamab mafodotin. 
Infusion-Related Reactions 
IRRs are expected for biologic agents. The majority of IRRs were non-serious and Grade 
1 or Grade 2 in severity. In DREAMM-2, IRRs occurred in 21% of participants receiving 
belantamab mafodotin 2.5 mg/kg. Symptoms of IRRs have included chills, asthenia, 
hypertension, lethargy, pyrexia, nausea, diarrhea, tachycardia, hypotension, and vomiting. 
Most IRRs occurred with the first infusion and few participants experienced IRRs with 
subsequent infusions. 
Although not protocol-mandated, pre-medications for IRR prophylaxis (including 
paracetamol, antihistamines, and steroids) were administered to 26% to 27% of 
participants. One participant (2.5 mg/kg cohort) discontinued treatment due to IRRs 
(Grade 3 IRRs at first and second infusion). 
2.2.3.3. 
Pharmacokinetics and Pharmacodynamics in Humans 
The pharmacokinetics and pharmacodynamics of belantamab mafodotin (ADC, including 
complex with soluble BCMA [sBCMA]), total mAb (including complex), and 
cys-mcMMAF were investigated in 291 participants with RRMM after IV administration 
at doses from 0.03 to 4.6 mg/kg Q3W in Study BMA117159 (n=73) and at doses of 2.5 
or 3.4 mg/kg Q3W in Study 205678 (n=218). 
Maximum concentrations (Cmax) of belantamab mafodotin and total mAb were observed 
at or shortly after the end of infusion, while cys-mcMMAF Cmax values were generally 
observed on Day 2. On a molar basis, plasma concentrations of cys-mcMMAF were <1% 

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of belantamab mafodotin concentrations. There was limited accumulation (less than 
2-fold) of belantamab mafodotin or cys-mcMMAF during subsequent cycles. 
Belantamab mafodotin pharmacokinetics were well described by a linear, 
two-compartment population model, with a time-varying decrease in clearance (CL) in a 
population pharmacokinetic analysis. At Cycle 1, belantamab mafodotin had a systemic 
CL of 0.92 L/day, steady-state volume of distribution (Vss) of 10.8 L, and an elimination 
half-life of 12 days in participants with RRMM in Study 205678. Over time, CL was 
reduced by 28%, resulting in an elimination half-life of 14 days. The time to 50% change 
in CL was approximately 50 days. 
No clinically significant differences in the pharmacokinetics of belantamab mafodotin or 
cys-mcMMAF were observed based on age (34 to 89 years), sex, race (African 
American/Black and White), body weight (42 to 130 kg), mild or moderate renal 
impairment (estimated glomerular filtration rate [eGFR] ≥30 ml/min/1.73m2) or mild 
hepatic impairment (National Cancer Institute-Organ Dysfunction Working Group 
classification). Higher serum levels of 2-microglobulin, immunoglobulin G (IgG), and 
sBCMA and lower levels of albumin are associated with more advanced MM or a higher 
MM disease burden. Higher baseline IgG and sBCMA levels and lower baseline albumin 
levels were associated with higher belantamab mafodotin CL leading to lower average 
concentration and concentration at the end of the dosing interval (Ctau) of belantamab 
mafodotin. Higher baseline IgG and sBCMA levels were associated with higher 
cys-mcMMAF central volume of distribution, leading to lower cys-mcMMAF Cmax. 
In non-clinical studies, cys-mcMMAF had limited metabolic CL. In vitro data suggested 
that belantamab mafodotin and cys-mcMMAF are unlikely to perpetrate a drug-drug 
interaction or to be a victim of a drug-drug interaction with inhibitors or inducers of 
cytochromes P450. Cys-mcMMAF was an in vitro substrate of organic anion transporting 
polypeptides (OATP)1B1 and OATP1B3, multidrug resistance associated proteins 
(MRP)1, MRP2, and MRP3, a borderline substrate of bile salt export pump, and a 
possible substrate of P-glycoprotein (P-gp). After the administration of belantamab 
mafodotin to participants with RRMM, only intact cys-mcMMAF was detected in pooled 
human urine, with no evidence of other MMAF-related urinary metabolites. 
Free sBCMA levels were measured in Study BMA117159 and Study 205678. All 
participants exhibited reductions in free sBCMA concentration at end of infusion 
compared to baseline at Cycle 1, with a return to near-baseline level by 7 days after 
dosing, reflecting binding of belantamab mafodotin to sBCMA. Maximum decreases 
ranged from 2 to 97%, which were qualitatively dose-dependent, with larger reductions in 
free sBCMA at higher doses. 
Exposure-response analyses performed for Study 205678 and/or Study BMA117159 
found that ocular safety endpoints were most strongly associated with belantamab 
mafodotin exposure, while efficacy endpoints had a weaker association with belantamab 
mafodotin exposure. Both safety and efficacy endpoints were associated with participant 
characteristics. Belantamab mafodotin Ctau was associated with probability of corneal 
events and keratopathy, and cys-mcMMAF Cmax was associated with probability of 
thrombocytopenia. Probability of occurrence of dry eye, blurred vision, neutropenia, and 

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IRR were not associated with an exposure measure. In addition, the results of the analysis 
of concentration against corrected QT interval (QTc) demonstrated that belantamab 
mafodotin or cys-mcMMAF did not have a significant effect on cardiac repolarization. 
Additional information related to belantamab mafodotin clinical pharmacokinetics, 
pharmacodynamics, and exposure-response relationships can be found in the current 
version of the Investigator’s Brochure. 
2.3. 
Benefit/Risk Assessment 
The following section will address the benefit/risk assessment for this study and the 
population to be enrolled. More detailed information about the known and expected 
benefits and risks and reasonably expected AEs of belantamab mafodotin may be found 
in the current versions of the Investigator’s Brochure and the local approved product 
label, where applicable. 

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2.3.1. 
Risk Assessment 
Potential Risk of Clinical Significance 
Summary of Data/Rationale for Risk 
Mitigation Strategy 
Study Treatment (belantamab mafodotin) 
Keratopathy (changes to the corneal 
epithelium, potentially resulting in 
vision changes) 
Changes in the corneal epithelium on ocular examination have been 
frequently observed with belantamab mafodotin and were most commonly 
associated with keratopathy (changes in the corneal epithelium upon 
examination), blurred vision, dry eyes, photophobia and changes in visual 
acuity. 
Participants with a history of dry eye were more prone to develop changes 
in the corneal epithelium. 
Based on available follow-up data, vision returned to, or near, baseline in 
most cases. 
• 
Active monitoring of the corneal epithelium and 
visual acuity as outlined in the SoA (Section 1.3) 
• 
Evaluation and management by an eye care 
professional.  
• 
Dose modification guidelines are outlined in 
Section 6.5 
Thrombocytopenia 
Belantamab mafodotin may cause transient thrombocytopenia in some 
participants which, for most cases, recovered between doses. 
In study 205678, which included participants treated with belantamab 
mafodotin 2.5 mg/kg, thrombocytopenia was noted in 38% of participants 
and ranged between Grade 1 to 4 in severity. 
• 
Routine monitoring of hematologic panels as outlined 
in the SoA (Section 1.3) 
• 
Supportive therapy per local medical practice (e.g., 
platelet transfusion) 
• 
Dose modification guidelines are outlined in 
Section 6.5.3 
Nephrotoxicity 
Nonclinical safety experiments have demonstrated primary glomerular 
injury and tubular degeneration/regeneration (in rat and monkey). These 
morphologic changes were accompanied by large molecular weight 
proteinuria (albuminuria) and enzymuria. Single-cell necrosis of the kidney 
and bladder urothelium was also noted in the chronic study. The renal 
changes were dose-dependent and reversible. Severe tubular 
degeneration/regeneration and marked glomerulonephritis as a result of 
immune complex disease associated with ADA led to the early euthanasia 
of 1 monkey following 5 weekly doses of 10 mg/kg. 
Increased ACR (albuminuria) has been reported in participants receiving 
belantamab mafodotin not indicative of disease progression and, in such 
cases, appropriate monitoring and dose modification should be considered. 
• 
Kidney function monitoring including 
albumin/creatinine ratio (ACR) 
• 
Education of participants on the need to maintain 
adequate urinary output 
• 
Dose modification guidelines for increased serum 
creatinine and urinary albumin/creatinine ratio are 
outlined in Section 6.5.3 

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Potential Risk of Clinical Significance 
Summary of Data/Rationale for Risk 
Mitigation Strategy 
Increased Infections due to 
immunosuppression or neutropenia 
In nonclinical studies, belantamab mafodotin has been associated with 
decrease in immunoglobulins in monkeys, at all doses. An increase in 
immunoglobulins was seen in rats (rats are not an antigen-specific species 
for belantamab mafodotin).  
Immunosuppression is frequently associated with an increased risk of 
infection. Serious and nonserious infections have been reported in 
belantamab mafodotin studies, including respiratory infections, pneumonia, 
and sepsis.  
Neutropenic events, including febrile neutropenia have been observed with 
belantamab mafodotin.  
• 
Participants with an active infection are excluded. 
• 
Monitoring for infections and immediate treatment of 
immunosuppression according to standard practice. 
• 
Routine monitoring of hematologic panels as outlined 
in the SoA (Section 1.3).  
• 
Supportive therapy per local medical practice (e.g., 
growth factors).  
• 
Prophylactic antibiotics, per local institutional 
guidance, in participants with Grade 3-4 neutropenia.  
• 
Immediate hospitalization of participants with febrile 
neutropenia.  
• 
Dose modification guidelines are outlined in 
Section 6.5.3  
Infusion-related Reactions (IRRs) 
IRRs were reported in participants treated with belantamab mafodotin. Most 
IRRs were Grade 1-2 and were manageable with medical treatment. 
• 
Close monitoring for signs of IRR 
• 
Consider premedication for IRR in participants at risk 
• 
If an IRR occurs, follow the guidance in Section 6.5.3 
Pneumonitis 
Nonclinical safety experiments have demonstrated the presence of 
progressive microscopic changes in the lungs (prominent alveolar 
macrophages associated with eosinophilic material; mixed 
perivascular/neutrophilic inflammation) in rats at all doses tested.  
Cases of pneumonitis, including fatal events, have been observed with 
belantamab mafodotin although a causal association has not been 
established.  
• 
Monitoring for clinical signs and symptoms related to 
pulmonary toxicity. If a participant experiences new 
or worsening pulmonary symptoms, (e.g., cough, 
dyspnea) without obvious etiology, further diagnostic 
tests and management should be performed and 
further treatment with belantamab mafodotin delayed 
are detailed in Section 6.5.3. 
• 
An overall benefit/risk assessment should be 
considered for the participant prior to continuing 
belantamab mafodotin treatment.  
• 
Further diagnostic tests and management will be 
implemented immediately in cases of suspected 
pneumonitis as described in Section 6.5.3. 
Abbreviations: ACR=albumin/creatinine ratio; ADA=anti-drug antibody; ALT=alanine aminotransferase; AST=aspartate aminotransferase; BCMA=B-cell maturation antigen; 
cys-mcMMAF=cysteine-maleimidocaproyl monomethyl auristatin F; CK=creatine kinase; CT=computed tomography; IRR=infusion-related reaction; LDH=lactate dehydrogenase; 
MRI=magnetic resonance imaging; PET=positron emission tomography; RRMM=relapsed or refractory multiple myeloma; SoA=Schedule of Activities; ULN-upper limit of normal. 
Note: Refer to the current version of the Belantamab Mafodotin Investigator’s Brochure for further information. 

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2.3.2. 
Benefit Assessment 
Efficacy has been demonstrated at 2.5 mg/kg belantamab mafodotin administered as an 
IV infusion Q3W until PD or unacceptable toxicity. 
Data from Study DREAMM-1, a Phase 1, FTIH, open-label, dose-escalation plus 
dose-expansion study of belantamab mafodotin 20 mg/mL in participants with RRMM, 
demonstrated substantial clinical efficacy at the dose of 3.40 mg/kg administered IV 
Q3W, with promising and clinically meaningful tumor response rates (see Section 2.2.3). 
The data from the DREAMM-2 study further demonstrated that belantamab mafodotin 
has significant clinical activity in participants with heavily pre-treated MM. In this study, 
both dose levels evaluated, 2.5 and 3.4 mg/kg, had a positive benefit/risk profile (see 
Section 2.2.3). 
Clinical responses were also observed in participants with dose interruptions and 
reductions for toxicities, hence belantamab mafodotin demonstrated remarkable clinical 
benefit and favorable efficacy response in participants with lower doses and/or longer 
dose intervals. 
Based on this profile, it is reasonable to hypothesize that this study may identify an 
alternative belantamab mafodotin dosing regimen that reduces the risk of corneal events 
without jeopardizing efficacy, to improve the overall benefit/risk profile in treated 
participants. If any of the investigational arms are stopped due to futility at the interim 
analysis and participants are still on treatment, participants will be given the opportunity 
to switch to 2.5 mg/kg Q3W (Arm A/control regimen) with dose modifications based on 
the keratopathy visual acuity (KVA) scale, which has already demonstrated benefit. 
2.3.3. 
Overall Benefit/Risk Conclusion 
Considering the measures to minimize risks to participants in this study, the potential 
risks identified in association with belantamab mafodotin administered at alternative 
doses are justified by the anticipated benefits that may be afforded to participants with 
RRMM. 

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3. 
OBJECTIVES AND ENDPOINTS AND ESTIMANDS 
Objectives and Endpoints 
Objectives 
Endpoints 
Primary 
To examine the corneal events associated 
with single-agent belantamab mafodotin using 
alternative dosing regimens in participants with 
RRMM in Arms B to D compared to Arm A  
Incidence rate of Grade ≥2 corneal events according 
to the KVA scale (see Table 8) 
Secondary 
To further evaluate the corneal safety and 
tolerability of single-agent belantamab 
mafodotin in all arms 
• 
Cumulative event rate of corneal events to 
Week 16 (KVA scale) 
• 
Incidence rate of corneal events by grade (KVA 
scale) 
• 
Exposure-adjusted incidence rate of corneal 
events by grade (KVA scale) 
• 
Median duration of dose delay 
• 
Percentage of participants requiring dose 
reductions, dose delays, and study treatment 
discontinuation due to corneal events (KVA scale) 
• 
Cumulative incidence of corneal events by grade 
(KVA scale) 
• 
Toxicity Index by assessment/visit 
• 
Duration of corneal events (KVA scale) 
• 
Percentage of time on study with corneal events 
(KVA scale) 
• 
Change in BCVA (ΔlogMAR) 

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Objectives 
Endpoints 
To evaluate the efficacy of single-agent 
belantamab mafodotin in all arms 
• 
ORR, defined as the percentage of participants 
with a confirmed PR or better (i.e., PR, VGPR, 
CR, and sCR) 
• 
Percentage of participants with a confirmed 
VGPR or better (i.e., VGPR, CR, and sCR) 
• 
TTR is defined as the time between the date of 
randomization and the first documented evidence 
of response (PR or better), among participants 
who achieve a response (i.e., confirmed PR or 
better) 
• 
DoR in responders, defined as the time from first 
documented evidence of PR or better until PD or 
death due to any cause 
• 
TTP, defined as the time from randomization until 
the earliest date of documented PD or death due 
to PD 
• 
PFS, defined as the time from randomization until 
the earliest date of documented PD or death due 
to any cause 
• 
OS, defined as the time from randomization until 
the date of death due to any cause 
Note: All efficacy endpoints are based on the 
2016 IMWG Response Criteria [Kumar, 2016] 
To evaluate the overall safety and tolerability 
of single-agent belantamab mafodotin in all 
arms 
• 
Instance of AEs (including ocular AEs) (CTCAE 
Version 5.0) and changes in laboratory 
parameters 
• 
Percentage of participants requiring dose 
reductions, dose delays, and study treatment 
discontinuation due to any AEs (CTCAE 
Version 5.0) 
To assess the pharmacokinetics of 
single-agent belantamab mafodotin in all arms 
Plasma belantamab mafodotin pharmacokinetic 
parameters, as data permit 
To assess anti-drug antibodies against 
single-agent belantamab mafodotin in all arms 
Incidence and titers of ADAs against belantamab 
mafodotin at each ADA time point 
Exploratory 
To assess the pharmacokinetics of 
cys-mcMMAF in all arms 
Plasma cys-mcMMAF pharmacokinetic parameters, 
as data permit 
To evaluate the toxicity over time of 
single-agent belantamab mafodotin in all arms 
Longitudinal ToxT AUC, as data permit 
To explore exposure-response relationships 
between belantamab mafodotin and 
cys-mcMMAF exposure and clinical endpoints 
for efficacy and safety in all arms 
Explore relationships between belantamab mafodotin 
exposure (e.g., Cmax, Cavg, or Ctau) and clinical 
endpoints (e.g., response, ocular toxicity), if data 
permit 
To explore the relationship between biological 
characteristics and clinical response in all 
arms 
Tumor- and blood-based analyses of DNA, RNA, and 
protein changes including, but not limited to, baseline 
and on-treatment sBCMA, BCMA expression on 
myeloma cells, and peripheral immune cell numbers 
and phenotypes 

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Objectives 
Endpoints 
To evaluate the safety and tolerability of 
single-agent belantamab mafodotin with dose 
modifications based on ocular symptoms, 
visual acuity assessments based on 
self-reported symptomatic AEs, and corneal 
findings (Arm E only) 
• 
Changes from baseline in pre-specified 
symptomatic AEs and impacts as measured by 
the PRO-CTCAE 
• 
Changes from baseline and proportion of 
participants with within-participant meaningful 
change in self-reported ocular symptoms and 
related impacts as measured by OSDI 
• 
Level of overall bother/tolerability as measured by 
the single item FACT-GP5 
To evaluate and compare changes in 
symptoms and HRQoL in all arms 
• 
Frequency and severity/intensity of symptomatic 
AEs as measured by the PRO-CTCAE 
• 
Changes from baseline and within-participant 
meaningful change in self-reported ocular 
symptoms and related impacts as measured by 
the OSDI 
• 
Level of overall bother/tolerability as measured by 
the single-item FACT-GP5 
• 
Change from baseline in HRQoL as measured by 
the EORTC-QLQ-C30 and EORTC-QLQ-MY20 
• 
Global cancer symptoms severity and change as 
measured by the PGIS/PGIC 
To evaluate the feasibility of dosing 
modifications based on ocular symptoms, 
visual acuity assessments, and corneal 
findings (Arm E) compared to dosing 
modifications based on KVA scale (Arm A). 
The incidence of keratopathy (all grades), visual 
acuity changes, ocular symptoms, related impacts 
based on OSDI, and corneal findings in the symptom-
based dose modification arm will be compared to the 
selected standard dose modification control arm. 
To evaluate in silico individualized dosing by 
ISS stage or other disease characteristics at 
baseline using virtual treatment arms 
Efficacy and safety endpoints will be calculated for 
virtual treatment arms created by combination of 
participants selected from the study treatment arms 
based on disease characteristics (e.g., ISS stage) 
To investigate the relationship between host 
genetic variation and the study treatment in all 
arms 
Effect of host genetic variation on response to study 
treatment including, but not limited to, belantamab 
mafodotin 
Abbreviations: ADA=anti-drug antibody; AE=adverse event; AUC=area under the curve; BCVA=best corrected visual 
acuity; BCMA=B-cell maturation antigen; Cavg=average concentration; Cmax=maximum concentration; 
CR=complete response; Ctau=concentration at the end of the dosing interval; CTCAE=Common Terminology 
Criteria for Adverse Events; cys-mcMMAF=cysteine-maleimidocaproyl monomethyl auristatin F; 
ΔlogMAR=change in logarithm of the minimum angle of resolution; DNA=deoxyribonucleic acid; DoR=duration of 
response; EORTC-QLQ-C30=European Organisation for Research and Treatment of Cancer Quality of Life 
Questionnaire 30-item Core Module; EORTC-QLQ-MY20=European Organisation for Research and Treatment of 
Cancer Quality of Life Questionnaire 20-item Multiple Myeloma Module; FACT-GP5=Functional Assessment of 
Cancer Therapy – General; HRQoL=health-related quality of life; IMWG=International Myeloma Working Group; 
KVA=keratopathy visual acuity; MRD=minimal residual disease; NGS=next generation sequencing; ORR=overall 
response rate; OS=overall survival; OSDI=Ocular Surface Disease Index; PD=progressive disease; 
PFS=progression-free survival; PGIC=Patient Global Impression of Change; PGIS=Patient Global Impression of 
Severity; PR=partial response; PRO-CTCAE=Patient-Reported Outcomes version of the Common Terminology 
Criteria for Adverse Events; RNA=ribonucleic acid; RRMM=relapsed or refractory multiple myeloma; 
sCR=stringent complete response; sBCMA=soluble B-cell maturation antigen; ToxT=toxicity over time; TTP=time 
to progression; TTR=time to response; VGPR=very good partial response. 

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Primary Estimand 
The primary clinical question of interest is: What is the impact on the incidence of 
Grade ≥2 corneal events when belantamab mafodotin is administered at alternate dose 
regimens relative to the DREAMM-2 established 2.5 mg/kg Q3W dosing regimen? 
The estimand is described by the following attributes: 
• 
Population: Participants with RRMM who have received 3 or more lines of prior 
therapy 
• 
Endpoint: Incidence rate of Grade ≥2 corneal events according to the KVA scale 
• 
Treatment condition: Different dosing regimen compared to control 
• 
Intercurrent event: Not applicable 
• 
Summary measure: Estimates of incidence rate of Grade ≥2 corneal events 
(KVA scale) 
• 
Rationale: Alternative dosing regimens of single agent belantamab mafodotin will be 
explored in Study 209628 to determine if an improved overall benefit/risk profile 
can be achieved by modifying the belantamab mafodotin dose, schedule, or both. 

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4. 
STUDY DESIGN 
4.1. 
Overall Design 
Study 209628 (DREAMM-14) is a Phase 2, randomized, parallel, open-label, study of 
belantamab mafodotin administered as a single-agent to participants with RRMM. The 
study has 5 arms: Arm A, a control arm (2.5 mg/kg Q3W); Arms B through D, 3 arms 
with dosing alternatives; and Arm E, a fifth exploratory arm to evaluate the feasibility of 
dosing 1.9 mg/kg every 6 weeks (Q6W) based on ocular symptoms (patient-reported 
symptoms using the OSDI), visual acuity assessments (Snellen chart or equivalent), and 
corneal findings (KVA scale). All enrolling study sites will participate in Arms A to D; 
site participation in Arm E is optional and based on site interest and ability. 
The treatment arms are as follows and a study schema is provided in Section 1.2. 
• Arm A: 2.5 mg/kg Q3W  
o Rationale for Arm A: control 
o Dose modification for corneal events: see Section 6.5.1 (dose reduction to 
1.9 mg/kg allowed) 
• Arm B: 1.9 mg/kg Q3W 
o Rationale for Arm B dosing: see Section 4.3 
o Dose modification for corneal events: see Section 6.5.1 (dose reduction to 
1.4 mg/kg allowed) 
• Arm C: 2.5 mg/kg Q6W 
o Rationale for Arm C dosing: see Section 4.3 
o Dose modification for corneal events: see Section 6.5.1 (dose reduction to 
1.9 mg/kg allowed) 
• Arm D: 1.9 mg/kg Q6W 
o Rationale for Arm D dosing: see Section 4.3 
o Dose modification for corneal events: see Section 6.5.1 (dose reduction to 
1.4 mg/kg allowed) 
• Arm E: 1.9 mg/kg Q6W with dose modifications based on ocular symptoms, 
visual acuity assessments, and corneal findings 
o Rationale for Arm E dosing: see Section 4.4 
o Dose modification for corneal events: see Section 6.5.2 (dose reduction to 
1.4 mg/kg allowed) 
Participants in Arm A will use the DREAMM-2 established 2.5 mg/kg Q3W dosing 
regimen. Participants in Arm C will receive a starting dose at 2.5 mg/kg belantamab 
mafodotin, but dosing will occur at Q6W intervals. Participants in Arms B, D, and E will 
start at a reduced dose of belantamab mafodotin (1.9 mg/kg) and continue dosing at Q3W 
(Arm B) and Q6W intervals (Arms D and E). Each dosing regimen has 1 allowed dose 
reduction: from 2.5 mg/kg to 1.9 mg/kg in Arms A and C, E and from 1.9 mg/kg to 
1.4 mg/kg in Arms B, D, and E. 

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Participants in all arms will have Q3W ophthalmic examination and monitoring (see 
Section 8.3.5.1). All ophthalmic examinations will be performed by a qualified eye care 
specialist (as defined in Section 10.1). 
All arms except Arm E will follow dose modification due to corneal events as per the 
KVA scale (see Table 8). In contrast, Arm E will use a symptom-based dose modification 
approach before each dose, in the oncologist’s office; specifically, ocular symptoms and 
visual acuity assessments using the OSDI and Snellen chart or equivalent, respectively 
(in addition to corneal examination findings according to the KVA scale), will be used to 
inform dose modification decisions (see Table 9). Note: Although not determining dose 
modification decisions, corneal events (corneal findings and BCVA) graded per the KVA 
scale will still be recorded for all participants in Arm E throughout the study. 
Participants in all arms will be treated until PD (confirmed by 2016 IMWG response 
criteria [Kumar, 2016]), unacceptable toxicity, or death. The study consists of a 
screening/baseline period, a treatment period, and a post-treatment follow-up period. The 
primary analysis will be performed at least 9 months after the first response of the last 
responder (i.e., PR, VGPR, CR, and sCR) or 12 months after the last participant is 
randomized into Arms A to D, whichever comes first. The study duration is anticipated to 
be approximately 28 months. 
Following 15 months after LSFD, DREAMM-14 study may move into PACT and/or a 
managed access program/drug supply program, to allow patients who are still receiving 
benefit from belantamab mafodotin to continue receiving treatment. For PACT, the 
collection of new data for all recruited participants who no longer receive study treatment 
will stop entirely and the clinical study database will be closed. A participant is 
considered to have completed the study if they have completed all periods of the study 
including the last visit. Those participants still benefiting from study treatment in the 
opinion of their treating physician may continue to receive study treatment in the PACT 
phase, and only serious adverse events (SAEs), AEs leading to treatment discontinuation, 
overdose, and pregnancy cases, and pre-specified ocular data will be reported directly to 
GSK. 
The study will end when the last patient had their last visit (last subject last dose plus 
70 days of AE reporting period or 15 months after LSFD, whichever comes last). 
4.2. 
Scientific Rationale for Study Design 
The study objectives and endpoints will generate data to explore alternative dosing 
regimens of single-agent belantamab mafodotin and determine if an improved overall 
benefit/risk profile can be achieved by modifying the belantamab mafodotin dose, 
schedule, or both. 
The primary endpoint, incidence of Grade ≥2 corneal events based on the KVA scale, 
was selected to demonstrate clinically relevant changes in ocular toxicity associated with 
belantamab mafodotin and takes into account not only the incidence rate of ocular 
toxicity but also the severity of the ocular toxicity. 

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Because ocular toxicity caused by belantamab mafodotin is multifactorial and complex, a 
range of secondary endpoints was selected to better understand and describe the different 
aspects of the toxicity, including features that are of clinical and participant interest, such 
as severity of the ocular toxicity, the duration of the event, the recurrence of events, and 
how this impacts vision-related activities. 
4.2.1. 
Participant Input into Study Design 
The perspective of participants was sought in the final design of this study. The sponsor’s 
Oncology Patient Council was asked to comment on the justification for the alternate 
arms and to provide input on the outcomes that are most important to them. 
4.3. 
Justification for Selected Doses and Schedules 
The control arm will use belantamab mafodotin at the dosing regimen of 2.5 mg/kg IV 
Q3W, which has demonstrated efficacy with an ORR of 31% (97.5% CI: 20.8%, 42.6%) 
in heavily pre-treated participants with RRMM in the pivotal DREAMM-2 study [Lonial, 
2020]. The present study, 209628 (DREAMM-14), will enroll the same population as 
enrolled in DREAMM-2 study. The overall objective is to explore whether alternative 
dosing regimens with lower dose intensity of single-agent belantamab mafodotin can 
improve the benefit/risk profile (i.e., can reduce the risk of corneal events without a 
clinically meaningful decrease in efficacy). 
A longitudinal mathematical model of the time-course of corneal events (KVA scale) was 
developed based on data from DREAMM-2 and a longitudinal model of the time-course 
of efficacy (serum M protein) was developed based on data from the participants who 
were followed for efficacy by serum M protein in the FTIH study BMA117159 
(DREAMM-1) and DREAMM-2. These models were combined with the population 
pharmacokinetic model to simulate efficacy and safety data over time for each candidate 
dosing regimen. Both studies that provided the data for the model development studied 
one planned dosing schedule, Q3W, with most participants receiving a starting dose of 
2.5 mg/kg or higher; therefore, some of the simulated regimens are outside the data used 
for model development. 
The candidate dosing regimens were diverse in terms of individual dose levels (from 
0.83 to 2.5 mg/kg) and dosing intervals (from once weekly to every 9 weeks [Q9W]). The 
maximum planned dose intensity was 2.5 mg/kg Q3W. The simulations incorporated 
adaptive dose modifications due to corneal events in accordance with the prescribing 
information and treatment discontinuation due to PD based on the International Myeloma 
Working Group (IMWG) response criterion for serum M protein. The simulations used 
the same participants (DREAMM-2, n=218) for each dosing regimen to facilitate 
comparison of the results. 
The results of the simulations were evaluated by assessing predicted reductions in corneal 
events endpoints based on simulated Q3W assessment visits (e.g., probability of 
Grade 2 or Grade 3 events on the KVA scale, proportion of time on study with 
Grade 2 events on the KVA scale), and corresponding predicted changes in efficacy 
(ORR, VGPR). In addition, cumulative doses (planned as well as predicted in the 
simulations) were summarized. 

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Alternative dosing regimens, all with lowered dose intensity, showed a simultaneous loss 
of efficacy with reduction of corneal events. More frequent dosing at a lower dose with 
the same planned cycle dose (e.g., 0.83 mg/kg once weekly or 1.25 mg/kg on Days 1 and 
8 of a three-week cycle) led to a larger relative reduction in efficacy compared to the 
relative reduction in corneal events and was therefore not pursued. Higher individual 
doses early in the dosing regimen appeared to be better from a benefit/risk perspective 
(e.g., initiating treatment at 2.5 or 1.9 mg/kg compared to 1.25 or 0.9 mg/kg). Longer 
dosing intervals early in a dosing regimen (e.g., Q9W) resulted in more early 
discontinuations due to PD. 
Three candidate regimens were selected for evaluation in this study: 
• 
Arm B: 1.9 mg/kg Q3W 
• 
Arm C: 2.5 mg/kg Q6W 
• 
Arm D: 1.9 mg/kg Q6W 
Each dosing regimen has 1 allowed dose reduction: from 2.5 mg/kg to 1.9 mg/kg in 
Arms A and C and from 1.9 mg/kg to 1.4 mg/kg in Arms B, D, and E. 
These investigational regimens were selected to include regimens that were predicted to 
have varying levels of reduction in corneal toxicity (rate of Grade 3 corneal toxicity 
[KVA scale]) with associated predicted reductions in ORR. In addition, they incorporate 
diversity in dosing approaches (e.g., lower dose at treatment initiation, longer dosing 
interval). Arms B and D investigate a lower initial dose (1.9 mg/kg) compared to the 
control arm and allow reduction to 1.4 mg/kg. Arms C and D investigate a longer dosing 
interval (Q6W) compared to the control arm. 
Based on the planned dosing regimens, Arms B, C, and D will deliver 76%, 50%, and 
38%, respectively, of the cumulative dose in the control Arm A. However, Arms B, C, 
and D are predicted to deliver approximately 83%, 70%, and 57%, respectively, of the 
cumulative dose in Arm A, based on the predicted median cumulative doses for the 
4 treatment arms at 12, 24, and 36 weeks after initiation of treatment. The latter is based 
on simulations which incorporate dose delays and reductions for ocular toxicity 
(KVA scale) and treatment discontinuation for PD. 
Thus, the study will investigate dosing regimens with reduced dose intensity to explore 
the impact of starting dose, frequency, and the combination of changing both starting 
dose and frequency and is expected to generate a dataset to facilitate more definitive 
analyses of dose and exposure factors associated with efficacy and corneal events. 
4.4. 
Rationale for the Investigation of Symptom-Based Dose 
Modifications (Arm E) 
Arm E of this study will assess the feasibility of “symptom-based dose modifications” 
where dose modification decisions of belantamab mafodotin will be determined based on 
ocular symptoms (patient-reported symptoms using the OSDI), visual acuity assessments 
(Snellen chart or equivalent), and corneal findings (KVA scale). The dosing regimen for 
Arm E is 1.9 mg/kg Q6W (i.e., the same as Arm D), and a standard ocular examination 
will be performed by an eye care specialist (Section 8.3.5.1). 

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Based on analyses conducted to support the interpretation of the OSDI in the context of 
ocular AEs associated with belantamab mafodotin, the OSDI has suggested content 
validity to cover the symptoms that participants frequently reported throughout 
qualitative interviews, moderate correlation with the KVA scale, is responsive to corneal 
events, and suggests an ability to distinguish between changes in grading of the 
KVA scale, on average. Scores for the OSDI range from 0 to 100, with higher scores 
meaning worse symptoms or functioning. Thresholds for meaningful change in 
participants with RRMM receiving BLENREP have been evaluated, with a deterioration 
of 8.3 for Ocular Symptoms and 16.7 for Vision-Related Functioning determined to be a 
meaningful change [Eliason, 2020; Popat, 2020]. 
The Snellen chart is an established tool for the assessment of visual acuity and is widely 
used in primary care, pediatric, and eye care specialist offices. Feedback from the GSK 
Oncology and Ophthalmology council has indicated that, with appropriate training, the 
oncology clinic staff will be capable of assessing visual acuity using a Snellen chart or 
equivalent. BCVA requires additional equipment that typically resides within an eye care 
specialist’s clinic, not the oncologist’s office. Therefore, to make this visual acuity 
assessment suitable for the oncologist clinic setting, visual acuity instead of BCVA will 
be used for the symptom-based dose modification decision assessment. 
Justification for exploring the feasibility of symptom-based dose modification in this 
study is based on the following observations: 
The original ocular monitoring plan set forth in the early belantamab mafodotin FTIH 
studies DREAMM-1 and DREAMM-2 was established due to the safety concern inherent 
with MMAF-containing ADCs; thus, a conservative and rigorous safety monitoring 
schedule was implemented (baseline and Q3W full eye examinations by an eye care 
specialist, including a slit lamp examination, to evaluate the corneal epithelium and 
BCVA assessment). 
Key findings from the pooled safety population (n=218) in DREAMM-2 have 
demonstrated that keratopathy is common (76%) and mostly Grade 3 (7% Grade 1, 
22% Grade 2, 45% Grade 3, and 0.5% Grade 4). 40% of events had resolved by the end 
of treatment (EOT) at the 13-month data cut, (29% with dose modification), while 
52% of cases had ongoing keratopathy (15% still on treatment, 8% in follow-up, and 
28% lost to follow-up or died). Nine cases of corneal epithelial erosion and ulceration 
have been observed across the belantamab mafodotin program and occurred after a mean 
of 10 cycles (range: 2 to 28 cycles). 
A recent analysis of 773 eye examinations in DREAMM-2 evaluating the association of 
corneal epithelium changes (keratopathy) with BCVA changes showed that Grade 3 to 4 
keratopathy was associated with minimal or no BCVA changes (Grade ≤1 in only 
12.5% [97/773] of evaluations). When patient-reported ocular symptoms were also 
considered, Grade 3 to 4 keratopathy was associated with Grade ≤1 BCVA changes or 
ocular symptoms in only 7.5% (58/773) of evaluations. Mild or no (Grade ≤2) 
keratopathy was associated with Grade ≤1 BCVA changes in 59.5% (460/773) of 
evaluations, or in 38.8% (300/773) of evaluations if also no ocular symptoms were 
reported [Terpos, 2021]. Overall, Grade 3 to 4 keratopathy was found in 24.9% (193/773) 
of evaluations, whereas Grade 2 to 4 BCVA changes or ocular symptoms occurred more 
frequently in 53.7% (415/773) of evaluations. Consequently, these findings suggest that 

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BCVA changes and ocular symptoms could be used as a valid alternative for belantamab 
mafodotin dose modification decisions and, with that, potentially reduce the frequency of 
a full examination by an eye care specialist. Furthermore, because BCVA changes or 
ocular symptoms occur more frequently than Grade 3 to 4 keratopathy, a symptom-based 
dose modification approach could be nimbler and, with that, mitigate the occurrence of 
Grade 4 keratopathy. This approach would alleviate burden on participants and the 
healthcare system. The safety of such a symptom-based dose modifications approach will 
be tested prospectively in Arm E of this study. 
In Arm E, participants will complete a symptom-based inquiry using the OSDI 
[Miller, 2010] (see Section 8.10.1.2) to assess ocular symptoms and functioning and the 
oncology clinic will conduct a Snellen chart or equivalent assessment to measure visual 
acuity, both within the oncologist’s office and before dosing. In parallel, the eye care 
specialist will perform the same eye examination as in the control arm (Section 8.3.5.1) 
Q3W. The results from the OSDI and the visual acuity assessment will be used to 
determine the dosing decision (Go or No-Go criteria; see Table 9); however, to ensure 
safety is not compromised while testing the novel approach, if the eye examination raises 
concerns (see Section 6.5.2), dosing will be withheld and consideration for restarting at a 
lower dose once resolved to Grade 1, will subsequently be made. 
Data from Arm E may warrant further exploration of the utility of symptom-based dose 
modifications of single-agent belantamab mafodotin. 
4.5. 
Participant Completion 
A participant will be considered to have withdrawn from the study if the participant has 
not died and is lost to follow-up, has withdrawn consent, at the investigator’s discretion is 
no longer being followed, or if the study is closed/terminated. 
4.6. 
End of Study Definition/Study Completion 
The primary analysis is planned to be performed at least 9 months after the first response 
of the last responder (i.e., PR, VGPR, CR, and sCR) or 12 months after the last 
participant is randomized into Arms A to D, whichever comes first. After the primary 
analysis, the study will continue, and participants will remain on-treatment and continue 
to be followed-up. A final analysis which includes updated OS and PFS, as well as 
selected safety data, will be performed. 
The final analysis will occur 15 months from LSFD and the DREAMM-14 study may 
move into PACT and/or a managed access program/drug supply program. For PACT, the 
collection of new data for all recruited participants who no longer receive study treatment 
will stop entirely and the clinical study database will be closed. As a part of PACT, 
participants may continue to receive belantamab mafodotin if they are gaining clinical 
benefit as assessed by the investigator until they meet any protocol-defined treatment 
discontinuation criteria. Although the clinical study database will be closed at the time of 
the final data cutoff, the study remains open until all participants discontinue study 
treatment and complete the 70-day safety follow-up and the end of study definition is 
reached. Only SAEs, overdose, and pregnancy cases, and prespecified ocular data will be 
reported directly to the GSK. 

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Dispensing of study treatment following 15 months after LSFD may utilize a manual 
resupply option, and drug accountability assessment will be performed at the site. All 
participants will be monitored and receive follow-up care in accordance with standard 
local clinical practice. For participants who do continue to receive belantamab mafodotin 
beyond the time of the final data cut-off, investigators will continue to report all SAEs, 
overdose, and pregnancy cases up to 70 days after last dose of study treatment, and 
pre-specified ocular data (see SRM) will be reported until resolution unless the event is 
considered by the investigator to be unlikely to resolve or the participant is lost to 
follow-up, in accordance with Section 8.4.1. Additionally, any SAE and pre-specified 
ocular event that is ongoing at the time of the final data cut-off must be followed up to 
resolution unless the event is considered by the investigator unlikely to resolve or the 
participant is lost to follow-up.  
The end of study is defined when the last participant had their last visit (last participant 
last dose plus 70 days of SAE reporting period) or 15 months after LSFD, whichever 
comes last. A participant is considered to have completed the study if they have 
completed all periods of the study including the last visit. GSK retains the right to request 
additional information for any participant with ongoing AE(s)/SAE(s)/ocular events at 
the end of the study, if judged necessary. 
5. 
STUDY POPULATION 
Prospective approval of protocol deviations to recruitment and enrollment criteria, also 
known as protocol waivers or exemptions, is not permitted. 
5.1. 
Inclusion Criteria 
Participants are eligible to be included in the study only if all of the following criteria 
apply: 
5.1.1. 
Age 
1. Participant must be 18 years of age inclusive (or the legal age of consent in the 
jurisdiction in which the study is taking place; see Section 10.7) at the time of 
signing the Informed Consent Form (ICF). 
5.1.2. 
Type of Participant and Disease Characteristics 
2. Participant has Eastern Cooperative Oncology Group (ECOG) performance status of 
0 to 2 (see Section 10.8). 
3. Participant has a histologically or cytologically confirmed diagnosis of MM as 
defined by IMWG criteria [Rajkumar, 2016], and 
a. Has undergone stem cell transplant or is considered transplant ineligible, and 
b. Has failed at least 3 prior lines of anti-myeloma therapies, including an anti-CD38 
antibody (e.g., daratumumab) alone or in combination, and is refractory to an 
immunomodulatory agent (e.g., lenalidomide, pomalidomide) and a proteasome 
inhibitor (e.g., bortezomib, ixazomib, carfilzomib). 

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Note: See Section 10.3 for guidelines for the determination of the number of 
prior lines of therapy in multiple myeloma. 
Note: Refractory myeloma is defined as disease that is nonresponsive while on 
primary or salvage therapy or progresses within 60 days of last therapy. 
Non-responsive disease is defined as either failure to achieve at least minimal 
response or development of PD while on therapy [Rajkumar, 2011]. 
Note: Failed myeloma therapy is inclusive of refractory myeloma therapy or 
therapy stopped due to unacceptable toxicity. 
4. Participant has measurable disease with at least one of the following criteria: 
a. Serum M protein 0.5 g/dL (5 g/L), or 
b. Urine M protein 200 mg/24h, or 
c. Serum free light chain (FLC) assay: Involved FLC level 5 mg/dL (50 mg/L) 
and an abnormal serum FLC ratio (<0.26 or >1.65) 
5. Participants with a history of autologous stem cell transplant are eligible for study 
participation provided the following eligibility criteria are met: 
a. Transplant was >100 days before study enrollment, and 
b. Participant has no active infection(s), and 
c. Participant meets the remainder of the eligibility criteria outlined in this 
protocol. 
6. All prior treatment-related toxicities (defined by the National Cancer Institute 
Common Terminology Criteria for Adverse Events [NCI-CTCAE] Version 5.0) must 
be Grade ≤1 at the time of enrollment, except for alopecia and Grade 2 peripheral 
neuropathy. 
7. Life expectancy of at least 6 months, in the opinion of the investigator. 
5.1.3. 
Sex and Contraceptive/Barrier Requirements 
8. Contraceptive use by men or women should be consistent with local regulations 
regarding the methods of contraception for those participating in clinical studies. 
a. 
Female Participants 
A female participant is eligible to participate if she is not pregnant or breastfeeding 
and at least one of the following conditions apply: 
• 
Is not a woman of childbearing potential (WOCBP) as defined in Section 10.9, 
or 
• 
Is a WOCBP and using a contraceptive method that is highly effective (with a 
failure rate of <1% per year), preferably with low user dependency (as described 
in Section 10.9) during the treatment period and for at least 4 months after the 

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last dose of study treatment and agrees not to donate eggs (ova, oocytes) for the 
purpose of reproduction during this period. The investigator should evaluate the 
effectiveness of the contraceptive method in relationship to the first dose of 
study treatment. 
A WOCBP must have a negative highly sensitive serum pregnancy test (as required 
by local regulations) within 72 hours before the first dose (Cycle 1 Day 1) of study 
treatment (see Section 8.3.7). 
Additional requirements for pregnancy testing during and after study treatment are 
provided in Section 8.3.7 and the Schedule of Activities (SoA) (Section 1.3). 
The investigator is responsible for review of medical history, menstrual history, and 
recent sexual activity to decrease the risk for inclusion of a woman with an early 
undetected pregnancy. 
b. Male Participants 
Contraceptive use by men should be consistent with local regulations regarding the 
methods of contraception for those participating in clinical studies. 
Male participants are eligible to participate if they agree to the following conditions 
from the time of first dose of study treatment until 6 months after the last dose of 
study treatment to allow for clearance of any altered sperm: 
• Refrain from donating sperm, plus either: 
o Be abstinent from heterosexual intercourse as their preferred and usual 
lifestyle (abstinent on a long term and persistent basis) and agree to remain 
abstinent, or 
o Must agree to use contraception/barrier as follows: Agree to use a male 
condom, even if they have undergone a successful vasectomy, with female 
partner use of an additional highly effective contraceptive method with a 
failure rate of <1% per year as described in Section 10.9, when having sexual 
intercourse with a WOCBP (including pregnant females). 
5.1.4. 
Informed Consent 
9. Participant is capable of giving signed informed consent as described in 
Section 10.10 which includes compliance with the requirements and restrictions 
listed in the ICF and in this protocol. 
5.1.5. 
Other Inclusions 
10. Participant meets country-specific inclusion criteria described in Section 10.7, if 
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5.2. 
Exclusion Criteria 
Participants are excluded from the study if any of the following criteria apply: 
5.2.1. 
Medical Conditions 
1. Participant has symptomatic amyloidosis, active POEMS syndrome (polyneuropathy, 
organomegaly, endocrinopathy, myeloma protein, and skin changes), or active plasma 
cell leukemia at the time of screening. 
2. Participant currently has corneal epithelial disease, except nonconfluent superficial 
punctate keratitis (SPK). 
3. Participant has evidence of active mucosal or internal bleeding. 
4. Participant has presence of an active renal condition (infection, requirement for 
dialysis, or any other condition that could affect participant’s safety). Participants 
with isolated proteinuria resulting from MM are eligible, provided they fulfill 
adequate organ function inclusion criteria (Exclusion Criteria 24). 
5. Participant has any serious and/or unstable pre-existing medical condition, psychiatric 
disorder, or other conditions (including laboratory abnormalities) that could interfere 
with the participant’s safety, obtaining informed consent, or compliance with the 
study procedures. 
6. Participant has malignancies other than the disease under study are excluded, except 
for any other malignancy from which the participant has been disease-free for 
>2 years and, in the opinion of the principal investigator and GSK Medical Director, 
will not affect the evaluation of the effects of the study treatment on the currently 
targeted malignancy (MM). Participants with curatively treated non-melanoma skin 
cancer may be enrolled without a 2-year restriction. 
7. Participant has evidence of cardiovascular risk including any of the following criteria: 
a. 
Evidence of current clinically significant untreated arrhythmias, including 
clinically significant electrocardiogram (ECG) abnormalities including 
second degree (Mobitz Type II) or third degree atrioventricular block, or 
b. 
History of myocardial infarction, acute coronary syndromes (including unstable 
angina), coronary angioplasty, or stenting or bypass grafting 3 months before 
screening, or 
c. 
Class III or IV heart failure as defined by the New York Heart Association 
functional classification system (see Section 10.11). 
d. 
Uncontrolled hypertension. 
8. Participant is a pregnant or lactating female. 
9. Participant has an active infection requiring antibiotic, antiviral, or antifungal therapy. 
10. Participant has known human immunodeficiency virus (HIV) infection, unless the 
participant can meet all of the following criteria: 
a. Established anti-retroviral therapy (ART) for ≥4 weeks and HIV viral load 
<400 copies/mL, and 

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b. CD4+ T cell (CD4+) counts ≥350 cells/µL, and 
c. No history of acquired immunodeficiency syndrome-defining opportunistic 
infections within the last 12 months. 
Note: Consideration must be given to ART and prophylactic antimicrobials that 
may have a drug-drug interaction and/or overlapping toxicities with belantamab 
mafodotin or other combination products as relevant (Section 6.8.2). 
5.2.2. 
Liver Safety 
11. Participants with hepatitis B virus (HBV) will be excluded unless the criteria in can 
Table 5 be met. 
Table 5 
Criteria for Determining HBV Status 
Serology 
Screening 
During Study Treatment 
HBcAb+, HBsAg- 
• 
HBV DNA undetectable 
• 
Monitoring per protocol 
(Section 1.3) 
• 
Antiviral therapy started if 
HBV DNA becomes 
detectable 
HBsAg+ at screening or 
3 months before the 
first dose of study 
treatment 
• 
HBV DNA undetectable 
• 
Highly effective antiviral therapy started 
4 weeks before the first dose of study 
treatment 
• 
Baseline imaging per protocol 
(Section 1.3) 
• 
Participants with cirrhosis are excluded 
• 
Antiviral therapy 
maintained throughout 
study treatment 
• 
Monitoring and 
management per protocol 
(Section 1.3) 
Abbreviations: DNA=deoxyribonucleic acid; HBcAb=hepatitis B core antibody; HBsAb=hepatitis B surface antibody; 
HBsAg=hepatitis B surface antigen; HBV=hepatitis B virus. 
Note: Presence of HBsAb indicating previous vaccination will not exclude a participant. 
12. Participants with a positive hepatitis C antibody test result or a positive hepatitis C 
virus (HCV) ribonucleic acid (RNA) test result at screening or 3 months before the 
first dose of study treatment will be excluded unless the participant can meet one of 
the following criteria: 
d. Negative HCV RNA test result 
e. Successful antiviral therapy (usually 8 weeks duration), followed by a negative 
HCV RNA test result after a washout period of 4 weeks. 
13. Participant has cirrhosis or current unstable liver or biliary disease per investigator 
assessment, defined by the presence of ascites, encephalopathy, coagulopathy, 
hypoalbuminemia, esophageal or gastric varices, or persistent jaundice. 
Note: Stable non-cirrhotic chronic liver disease (including Gilbert’s syndrome or 
asymptomatic gallstones) is acceptable if a participant otherwise meets entry criteria. 
14. Participant has alanine aminotransferase (ALT) >2.5× upper limit of normal (ULN). 
15. Participants has total bilirubin >1.5×ULN (isolated total bilirubin >1.5×ULN is 
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5.2.3. 
Prior/Concomitant Therapy 
16. Participant has received systemic anti-myeloma therapy within ≤14 days or 
5 half-lives, whichever is shorter, before the first dose of study treatment. 
17. Participant has received plasmapheresis 7 days before the first dose of study 
treatment. 
18. Participant has received systemic therapy with high dose steroids (equivalent to 
60 mg prednisone daily for ≥4 days) administered to treat MM or non-MM disease 
within ≤14 days before the first dose of study treatment. 
19. Participant has received a prior allogenic stem cell transplant. 
Note: Participants who have undergone syngeneic transplant will be allowed, only if 
there is no history of graft versus host disease. 
20. Participant has used an investigational drug ≤14 days or 5 half-lives, whichever is 
shorter, before the first dose of study treatment or has received therapy with a 
monoclonal antibody ≤30 days before the first dose of study treatment, whichever is 
shorter. 
Note: Use of monoclonal antibodies for serious conditions unrelated to multiple 
myeloma, such as COVID, may be permitted after consultation with the GSK 
Medical Director. 
21. Participant has received prior treatment with an anti-BCMA targeted therapy or has a 
known immediate or delayed hypersensitivity or idiosyncratic reaction to drugs 
chemically related to belantamab mafodotin, or any of the components of the study 
treatment. 
22. Participant has received prior treatment with an antibody-drug conjugate. 
23. Participant has received any major surgery ≤4 weeks before the first dose of study 
treatment. An exception may be allowed for bone stabilizing surgery after 
consultation with the GSK Medical Director. 
5.2.4. 
Diagnostic Assessments 
24. Participants has inadequate bone marrow reserve or organ functions as demonstrated 
by any of the following criteria: 
a. 
Absolute neutrophil count <1.0×109/L 
b. 
Hemoglobin <8 g/dL 
c. 
Platelet count <50×109/L 
d. 
Spot urine (albumin/creatinine ratio) >500 mg/g (56 mg/mmol) 
e. 
eGFR <30 mL/min/1.73 m2 (as calculated by Modified Diet in Renal Disease 
equation, see Section 10.5) 
Note: Laboratory results obtained during screening must be used to determine 
eligibility criteria. In situations where laboratory results are outside the permitted 

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range, the investigator may re-test the participant and the subsequent within range 
screening result may be used to confirm eligibility. 
Note: Supportive care as needed, including transfusion of blood products or growth 
factors, before or during the study is allowed. 
5.3. Lifestyle Considerations 
Contact lenses are prohibited for participants while they are receiving belantamab 
mafodotin treatment. Contact lens use may be restarted after the last dose of study 
treatment once a qualified eye care specialist (see Section 10.1) confirms there are no 
other contraindications. For Arms A to E, the use of bandage contact lenses is permitted 
during study treatment as directed by the treating eye care specialist. 
No other lifestyle restrictions are required for participants in this study. 
5.4. Screen Failures 
A screen failure occurs when a participant who consents to participate in the clinical 
study is not subsequently randomized. A minimal set of screen failure information is 
required to ensure transparent reporting of screen failure participants to meet the 
Consolidated Standards of Reporting Trials (CONSORT) publishing requirements and to 
respond to queries from regulatory authorities. Minimal information includes 
demographics, screen failure details (including previous treatment with the 
 as a reason for screen failure), eligibility criteria, any protocol 
deviations, and any SAEs. 
Individuals identified as screen failures may be rescreened if the failure was based on 
elements of eligibility that may change, e.g., laboratory test results. Rescreening of a 
participant more than once requires discussion with the GSK Medical Director. 
Rescreened participants must be assigned a new unique participant number that is 
different from the initial number. 
5.5. 
Criteria for Temporarily Delaying Enrollment, 
Randomization, or Administration of Study Treatment 
Not applicable. 
6. 
STUDY TREATMENT AND CONCOMITANT THERAPY 
Study treatment is defined as any investigational treatment intended to be administered to 
a study participant according to the study protocol. 
6.1. 
Study Treatments Administered 
A summary of the identity and characteristics of the individual components of study 
treatment are included in the following sections. 
CCI

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6.1.1. 
Belantamab Mafodotin 
Belantamab mafodotin will be administered intravenously over approximately 
30-60 minutes at different doses in each of the 5 study arms as shown in Table 6. The 
dose to be administered is based on actual body weight measurement on Cycle 1 Day 1 
before dosing. For subsequent dosing, if the change in body weight is 10% from Cycle 1 
Day 1 (before dosing), the dose does not need to be recalculated. However, if the change 
of body weight is >10% (i.e., increased or decreased) from baseline, then the dose needs 
to be recalculated based on this new weight; which will become the new baseline for 
weight comparison at subsequent visits. The dose may be reduced to address toxicity 
according to protocol guidelines (Section 6.5). 
Table 6 
Study Arms and Treatment Administered (Belantamab Mafodotin) 
Arm Name 
A 
B 
C 
D, E 
Treatment Name on 
Label 
GSK2857916 for injection, 100 mg 
Type 
Biologic/drug (antibody-drug conjugate) 
Dose Formulation 
Lyophilized powder in single-use vial for reconstitution 
Unit Dose Strength 
100 mg/vial 
Dosage Levels 
2.5 mg/kga Q3W  
1.9 mg/kgb Q3W 
2.5 mg/kga Q6W 
1.9 mg/kg b Q6W 
Route of 
Administration/ 
Duration 
IV infusion over at least 30-60 minutesc, d 
Use 
Control 
Experimental 
Experimental 
Experimental 
AxMP, IMP, or NIMP 
IMP 
IMP 
IMP 
IMP 
Manufacturer/ 
Sourcing 
Manufactured and provided centrally by the sponsor (GlaxoSmithKline) 
Packaging and 
Labeling 
Study treatment will be provided as a lyophilized powder in a single vial. Each 
vial will be labeled as per country requirements. 
Dosing Instructions 
• 
Reconstitute belantamab mafodotin lyophilized powder 100 mg/vial with 
2.0 mL of sterile water for injection before use 
• 
Dilute belantamab mafodotin in normal 0.9% saline to the appropriate 
concentration for the dose. Doses of belantamab mafodotin are to be 
administered as an IV infusion via an infusion pump 
• 
See the current version of the Belantamab Mafodotin Investigator’s 
Brochure for compatible administration materials 
Current Aliases 
Belantamab mafodotin, BLENREP™ 
Abbreviations: AxMP=auxiliary medicinal product; IMP=investigational medicinal product; NIMP=non-investigational 
medicinal product; Q3W=every 3 weeks; Q6W=every 6 weeks. 
a. 
Dose reduction allowed to 1.9 mg/kg. 
b. 
Dose reduction allowed to 1.4 mg/kg. 
c. 
Infusions may be prolonged in the event of an infusion reaction. If multiple participants experience clinically 
significant infusion reactions, the infusion rate may be slowed for all future administrations of study treatment for 
all participants. Should this global change in infusion rate be required, it will be communicated to the sites in 
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d. 
Premedication (e.g., systemic corticosteroids) is not required unless deemed medically necessary by the 
investigator, in which case it should be administered according to institutional recommendations. 
6.2. 
Preparation, Handling, Storage, and Accountability 
See the Pharmacy Manual and product label for further guidance on administration of 
belantamab mafodotin. 
1. The investigator or designee must confirm appropriate temperature conditions have 
been maintained during transit for all study treatment received and any discrepancies 
are reported and resolved before use of the study treatment. 
2. Only participants enrolled in the study may receive study treatment and only 
authorized site staff may supply, prepare, or administer study treatment. All study 
treatments must be stored in a secure, environmentally controlled, and monitored 
(manual or automated) area in accordance with the labelled storage conditions with 
access limited to the investigator and authorized site staff. 
3. The investigator, institution, or the head of the medical institution (where applicable) 
is responsible for study treatment accountability, reconciliation, and record 
maintenance (i.e., receipt, reconciliation, and final disposition records). 
4. Further guidance and information for the final disposition of unused study treatment 
are provided in the Study Reference Manual. 
Precaution will be taken to avoid direct contact with the study treatment. A Material 
Safety Data Sheet describing occupational hazards and recommended handling 
precautions will be provided to the investigator. In the case of unintentional occupational 
exposure, site personnel are to notify the monitor, GSK Medical Director, and/or GSK 
study contact. 
6.3. 
Assignment to study intervention  
Methods to minimize bias in this clinical study include randomization and stratification 
as described in Table 7. 

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Table 7 
Methods to Minimize Bias 
Type of Study 
• 
Open-label 
Central 
randomization via 
IRT system 
• 
This is an open-label study; therefore, no blinding of treatment identity is 
needed. However, to ensure study integrity, steps will be taken to restrict 
sponsor access to key information while the study is ongoing and prevent 
data aggregation, except for where specified in the protocol (i.e., IDMC, 
see Section 9.5.1). 
• 
Upon completion of all the required screening assessments, eligible 
participants will be centrally randomized using a central IRT system, 
RAMOS NG, by the investigator or authorized site staff. 
• 
RAMOS NG allows study sites to register and randomize participants and 
also records stratification information. Randomization list will be done 
centrally using a randomization schedule generated by the GSK Clinical 
Statistics Department in RandALL NG, which will assign participants in 
either a 2:2:2:2:1 ratio to Arms A to E in parallel (at sites participating in 
optional Arm E) or a 1:1:1:1 ratio to Arms A to D in parallel (at sites not 
participating in optional Arm E). 
Note: For Arm E, in which dose modification decisions are informed by the 
results of the OSDI questionnaire, the OSDI must be available in the 
appropriate language in order for a participant to be randomized into this 
arm. If the OSDI is not available, the participant will be randomized into 
Arms A to D (1:1:1:1). 
Stratification 
1. ISS for MM (I vs II vs III) (see Section 10.2) 
2. Number of prior lines of anti-MM therapy (3 vs 4) (see Section 10.3)  
Abbreviations: GSK=GlaxoSmithKline; IRT=Interactive Response Technology; IDMC=Independent Data Monitoring 
Committee; ISS=International Staging System; MM=multiple myeloma. 
 
6.4. 
Study Treatment Compliance 
• 
When the individual dose for a participant is prepared from a bulk supply, the 
preparation of the dose will be confirmed by a second member of the study site staff. 
• 
When participants are dosed at the site, they will receive study treatment directly 
from the investigator or designee, under medical supervision. The date and time of 
each dose administered in the clinic will be recorded in the source documents. The 
dose of study treatment and study participant identification will be confirmed at the 
time of dosing by a member of the study site staff other than the person 
administering the study treatment. 
6.5. 
Dose Modification (Dose Reductions and Dose Delays) 
Arms A and C will use 2.5 mg/kg as the belantamab mafodotin starting dose, with 
one permitted dose reduction to 1.9 mg/kg. Arms B, D, and E will use 1.9 mg/kg as the 
belantamab mafodotin starting dose, with one permitted dose reduction to 1.4 mg/kg. See 
Section 4.3 for the rationale for the doses and schedules investigated in this study. 
If the participant cannot tolerate the drug after the allowed dose reduction of belantamab 
mafodotin, he or she must discontinue treatment for lack of tolerability. 

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In case of full resolution of symptoms which lead to dose reduction and after discussing 
with the GSK Medical Director, further treatment at the previous dose level may be 
considered by the investigator. 
If a dose is delayed, the participant should wait for the next scheduled dose to resume 
treatment. The reason for any dose delay must be documented in the participant’s eCRF 
and clinic record. In individual cases where in the judgment of the investigator waiting a 
full cycle to resume treatment after delay (skipping dose) related to toxicity which has 
resolved would be detrimental to the participant’s health and exceptional circumstances, 
the principal investigator should contact the GSK Medical Director to discuss an earlier 
restart. An earlier restart may be considered only for participants who have recovered 
from toxicity to Grade 1. The dosing with belantamab mafodotin cannot occur more 
frequently than every 21 days (±3-day window). In cases of dose delay, efficacy, safety, 
and ocular assessments must remain every 3 weeks in line with initial schedule from 
C1D1, which may result in 2 separate visits (1 for dosing, 1 for Q3 weekly assessments); 
thereafter, every effort should be made to eventually align subsequent dosing and Q3 
weekly visits to the original dosing schedule (C1D1) using the visit windows. 
Evaluations associated with a dose would be entered into the eCRF under the next 
scheduled cycle.  
Resuming treatment with belantamab mafodotin will be possible with or without dose 
reduction after the toxicity has resolved to Grade 1 or less. 
6.5.1. 
Dose Modification for Corneal Events (Arms A to D) 
Corneal toxicity in Arms A to D will be graded using the KVA scale in Table 8. Dose 
modification guidelines as per Table 8 will be followed accordingly. 
Note: For Arm E, while the KVA scale will not be used for dose modification decisions, 
the KVA grade will be determined based on the eye care specialist assessment to allow 
endpoint analysis. 
Table 8 
KVA Scale and Dose Modification Guidelines for Corneal Toxicities 
for Belantamab Mafodotin Treatment for Arms A to D 
Grade 
Corneal Findingsa 
Change in 
Snellen-Equivalent BCVAb, c 
Recommended Dosage 
Modifications 
0 
Clear cornea 
First visit or no change from 
baseline 
Start or continue 
belantamab mafodotin at 
current dose 
1 
Mild (nonconfluent) SPK 
Visual acuity has decreased 
not more than 0.1 logMAR 
units from baseline 
Start or continue 
belantamab mafodotin at 
current dose 
2 
Presence of peripheral 
confluent SPK, patchy 
microcyst-like deposits, 
peripheral subepithelial 
haze, or peripheral stromal 
opacity 
Visual acuity has decreased 
more than 0.1 logMAR units, 
but not more than 
0.3 logMAR unitsd, from 
baseline and is equal to or 
better than 1.0 logMAR 
(20/200) 
Withhold belantamab 
mafodotin until both corneal 
findings and visual acuity 
improve to Grade 1 or better 
and then resume at the 
same dose 

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Grade 
Corneal Findingsa 
Change in 
Snellen-Equivalent BCVAb, c 
Recommended Dosage 
Modifications 
3 
Presence of central 
confluent SPK, diffuse 
(confluent) microcyst-like 
deposits, central 
subepithelial haze, or central 
stromal opacity 
Visual acuity has decreased 
more than 0.3 logMAR unitsd 
from baseline and is equal to 
or better than 1.0 logMAR 
(20/200) 
Withhold belantamab 
mafodotin until both corneal 
findings and visual acuity 
improve to Grade 1 or better 
and then resume at a 
reduced dose 
4 
Corneal ulcere 
Visual acuity is worse than 
1.0 logMAR (20/200) 
Arms A-C: Consider 
permanent discontinuation 
of belantamab mafodotin. If 
continuing treatment, 
withhold belantamab 
mafodotin until both corneal 
findings and visual acuity 
improve to Grade 1 or better 
and then resume at a 
reduced dose 
Arm D: Permanently 
discontinue belantamab 
mafodotinf 
Abbreviations: BCVA=best corrected visual acuity; KVA=keratopathy visual acuity; logMAR=logarithm of the minimum 
angle of resolution; SPK=superficial punctate keratitis. 
a. 
Certain corneal findings are not considered to be related to treatment with belantamab mafodotin and are 
excluded from the KVA scale and dose modification criteria. These findings include the following: cataracts, 
macular degeneration, ocular traumatic events, retinal conditions (e.g., retinal hemorrhage, retinal vein 
thrombosis), and other findings that may arise as a result of pre-existing conditions. 
b. 
Snellen-equivalent BCVA is recommended to be tested on a visual acuity chart which has an approximately equal 
number of letters per line and equal spacing between lines. 
c. 
If visual acuity is worse than 1.0 logMAR (20/200) in each eye before to the first administration of belantamab 
mafodotin, recommended dosage modifications should be based on the corneal findings in the worst eye, not on 
visual acuity. 
d. 
A 0.3 logMAR unit change is a halving of the visual angle (e.g., 20/20 to 20/40) or (20/50 to 20/100), etc. 
e. 
Includes other corneal epithelial defects such as corneal erosions. 
f. 
Investigators who believe that further treatment of a participant with belantamab mafodotin is warranted (i.e., no 
other treatment options) may submit a request to the GSK Medical Director for the participant to resume study 
treatment after corneal findings and visual acuity improve to Grade 1 or better. GSK will review the details of the 
participant’s clinical status and ocular findings. If the GSK Medical Director and study team agree that further 
treatment with belantamab mafodotin is appropriate, the case will be escalated through the standard GSK medical 
governance process. If continued treatment is approved by GSK, treatment with belantamab mafodotin will be 
continued according to the dose modification guidelines; if not approved, the participant will be permanently 
discontinued from study treatment. 

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6.5.2. 
Dose Modifications Based on Ocular Symptoms, Visual Acuity 
Assessments, and Corneal Findings (Arm E) 
To determine dosing decisions for participants in Arm E, the oncology clinic will 
perform, on the date of or up to 3 days before dosing, a symptom-based inquiry using the 
OSDI to assess ocular symptoms and impacts on vision-related activities and visual 
acuity assessment using a Snellen chart or equivalent. The dosing decision (Go – 
Criteria A, or No-Go – Criteria B; Table 9) will be based on these results, however, if any 
of the following conditions are identified during the ocular examination (conducted by 
eye care specialist), then dosing will be withheld and consideration for restarting at a 
lower dose once resolved to “Criteria A” will subsequently be made: 
• 
Epithelial erosions and/or 
• 
Ulceration and/or 
• 
Significant sub-epithelial haze and/or 
• 
Perforation 
Table 9 
Dose Modification Guidelines for Belantamab Mafodotin Treatment 
for Arm E based on OSDI, Visual Acuity, and Corneal Findings 
 
Clinical Visual Symptoms OSDI, 
Visual Acuitya, and Corneal Findings 
Belantamab Mafodotin 
Dose Modificationb 
Criteria A 
Conducted in Oncologist’s Office: 
• 
OSDI Q1-5 if < “Half of the time” at baseline: 1 
category worsening 
• 
OSDI Q1-5 if ≥ “Half of the time” at baseline: no 
worsening 
• 
OSDI Q6-9 < “All of the time” 
• 
Visual acuity has decreased 0.1 logMAR units 
from baselinec 
Conducted by Eye Care Specialist: 
• 
No corneal findings of Grade 2 according to 
the KVA scale 
Continue treatment at the same 
dose 
Criteria Be 
Conducted in Oncologist’s Office: 
• 
OSDI Q1-5 if < “Half of the time” at baseline: 
≥2 category worsening 
• 
OSDI Q1-5 if ≥ “Half of the time” at baseline: 
any worsening 
• 
OSDI Q6-9 = “All of the time” (unless participant 
baseline is “All of the time”) 
• 
Visual acuity has decreased >0.1 logMAR units 
from baselinec 
Conducted by Eye Care Specialist: 
• 
Corneal findings of Grade 2 according to the 
KVA scale 
Hold treatment until resolves to 
Criteria A, then resume treatment 
at 1.4 mg/kg Q6Wd 
For corneal findings of Grade 4 
according to the KVA scale: 
Permanently discontinue 
treatmente 

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Abbreviations: KVA=keratopathy visual acuity; logMAR= logarithm of the minimum angle of resolution; OSDI=Ocular 
Surface Disease Index; Q6W=every 6 weeks. 
Note: OSDI baseline is defined as C1D1. OSDI categories include: “None of the time”, “Some of the time”, “Half of the 
time”, “Most of the time”, “All of the time”. 
a. 
If visual acuity baseline changes (e.g., due to cataract surgery) then the new visual acuity baseline has to be used 
for subsequent assessment. 
b. 
Dose modification should be based on the most severe grade. If eyes differ in severity, the dose modification 
guideline should be applied based on the more severe eye. 
c. 
Visual acuity will be assessed in both eyes with and without pinhole (i.e., 4 readings). If the reading in one eye 
differs with and without pinhole, the better value for that eye will be used. The findings from the eye with the 
largest visual acuity change from baseline will be used in the dosing decision. Note: A 0.3 logMAR unit change is 
a halving of the visual angle (e.g., 20/20 to 20/40); or (20/50 to 20/100), etc. 
d. 
If any criteria are met, where “ANY” refers to each item in each bullet, i.e., each question (Q1 through Q9) should 
be assessed separately. 
e. 
Investigators who believe that further treatment of a participant with belantamab mafodotin is warranted (i.e., no 
other treatment options) may submit a request to the GSK Medical Director for the participant to resume study 
treatment after corneal findings and visual acuity improve to Grade 1 or better. GSK will review the details of the 
participant’s clinical status and ocular findings. If the GSK Medical Director and study team agree that further 
treatment with belantamab mafodotin is appropriate, the case will be escalated through the standard GSK medical 
governance process. If continued treatment is approved by GSK, treatment with belantamab mafodotin will be 
continued according to the dose modification guidelines; if not approved, the participant will be permanently 
discontinued from study treatment. 
6.5.3. 
Dose Modification for Treatment-Related Non-Ocular Adverse 
Events (All Arms) 
For all other non-ocular belantamab mafodotin-related toxicities Table 10 and Table 11 
will be followed, with Arms A and C (starting dose 2.5 mg/kg) reducing to 1.9 mg/kg and 
Arms B, D, and E (starting dose 1.9 mg/kg) reducing to 1.4 mg/kg. 
Table 10 
Dose Modification Guidelines for Belantamab Mafodotin-Related 
AEs 
Toxicity 
Grade/ 
Description of 
Toxicity 
Recommendations 
Serum creatinine 
Graded according to 
NCI-CTCAE criteria 
Grade 2 
>1.5 - 3.0 x baseline;  
>1.5 - 3.0 x ULN 
• 
Repeat within 48 hours if elevation cannot be 
explained by concomitant sepsis, TLS, other 
severe condition with fever or dehydration. 
• 
If confirmed: withhold belantamab mafodotin, 
initiate treatment and monitoring as clinically 
indicated, and follow for resolution. 
• 
Discuss any further treatment with 
belantamab mafodotin with GSK Medical 
Director 
Grade 3  
>3.0 x baseline;  
>3.0 - 6.0 x ULN 
Or 
Grade 4 
>6.0 x ULN 
• 
Provide appropriate medical treatment 
• 
If drug related, permanently discontinue 
treatment with belantamab mafodotin  
• 
If due to another cause (such as sepsis, or 
dehydration), withhold treatment with 
belantamab mafodotin. Upon recovery to 
Grade 1, restart treatment at the same dose 
level. 

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Toxicity 
Grade/ 
Description of 
Toxicity 
Recommendations 
Spot urine (ACR) 
>2000 mg/g 
(or 224 mg/mmol) 
• 
Re-test (at least 7 days apart). 
• 
If not confirmed: continue treatment with 
belantamab mafodotin at current dose 
• 
If confirmed on re-test and no clear evidence 
of PD: 
o 
Withhold treatment with belantamab 
mafodotin 
o 
Repeat testing within 4 weeks 
o 
If spot urine <2000 mg/g (224 mg/mmol): 
may restart treatment with belantamab 
mafodotin with a dose reduction 
o 
If spot urine remains >2000 mg/g 
(224 mg/mmol) after 4 weeks: consider 
permanently discontinuing belantamab 
mafodotin, provide treatment as clinically 
indicated, and follow for resolution. 
Urine dipstick 
2+ 
• 
May continue treatment with belantamab 
mafodotin 
• 
Confirm by quantitative assessment using 
ACR (spot urine from first void) 
• 
If ACR >2000 mg/g at the next cycle, follow 
guidance for spot urine. 
3+ 
• 
Withhold treatment with belantamab 
mafodotin and follow for resolution 
• 
Perform quantitative assessment using ACR 
(spot urine from first void) 
Thrombocytopenia (on days of 
dosing) 
Grade 3 
• 
No bleeding: continue treatment with 
belantamab mafodotin with 1 dose level 
reduction; consider reverting to previous dose 
once thrombocytopenia recovers to Grade ≤2 
• 
With bleeding: withhold treatment with 
belantamab mafodotin and restart treatment 
after resolution with 1 dose level reduction 
• 
Consider additional supportive medical 
treatment (e.g., transfusion), as clinically 
indicated and per local practice 
Grade 4 
• 
Withhold treatment with belantamab 
mafodotin; consider restarting with 1 dose 
level reduction after resolution or transfused 
to Grade 3, only if there is no active bleeding 
at time of restart 
• 
If thrombocytopenia is considered 
disease-related, is not accompanied by 
bleeding, and recovers with transfusion to 
>25x109/L, continuing treatment with 
belantamab mafodotin with 1 dose level 
reduction may be considered after discussion 
with the GSK Medical Director 

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Toxicity 
Grade/ 
Description of 
Toxicity 
Recommendations 
Febrile neutropenia (graded 
according to NCI-CTCAE) 
Grades 3-4 
(defined as: single 
temperature of 38.3C or 
sustained temperature of 
38C for >1 h and ANC 
<1.0x109/L) 
• 
Withhold the treatment with belantamab 
mafodotin and immediately hospitalize 
participant with appropriate management, per 
local institutional guidance 
• 
Consider additional supportive medical 
treatment per local practice (e.g., growth 
factors) 
• 
Upon resolution, consider a dose reduction of 
belantamab mafodotin if neutropenia was 
drug-related 
Neutropenia without fever 
(graded according to 
NCI-CTCAE) 
Grade ≥3 
(defined as 
ANC <1.0x109/L) 
• 
If noted on Day 1 of any cycle, withhold 
treatment with belantamab mafodotin 
• 
Restart treatment with belantamab 
mafodotin at current dose once 
neutropenia resolves to Grade ≤2 (ANC 
≥1.0x109/L) on Day 1 of the subsequent 
cycle 
• 
Administer prophylactic antibiotics, per 
physician discretion and local institutional 
guidance; consider providing growth 
factors. 
• 
Local guidance must be followed for 
hematologic monitoring, if more 
conservative than the protocol SoA 
specifications. 
• 
In cases of frequent, recurrent 
neutropenia (ANC <1.0x109/L), consider 
dose reduction of belantamab mafodotin 
by 1 level 
IRRa 
Grade 2 
• 
Stop the infusion, provide appropriate medical 
treatment, and continue infusion at half the 
original infusion rate after resolution to 
Grade 0-1 
Grade 3 
• 
Further treatment with belantamab mafodotin 
must be discussed with GSK Medical 
Director. 
• 
Treatment continuation only allowed after 
resolution to Grade 1 and with 
pre-medication and extension of infusion time 
to 2-4 h 
• 
Any future infusion must be pre-medicated 
Grade 4 
• 
Permanently discontinue treatment with 
belantamab mafodotin 
Pneumonitis 
Grade 2 
• 
Withhold treatment with belantamab 
mafodotin 
• 
Upon resolution, restart treatment with 1 dose 
level reduction 
• 
If participant is already at the lowest dose 
level, then rechallenge with the same dose 
must be discussed with the GSK Medical 
Director 

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Toxicity 
Grade/ 
Description of 
Toxicity 
Recommendations 
Grades 3-4 
• 
Permanently discontinue treatment with 
belantamab mafodotin 
Abbreviations: ACR=albumin/creatinine ratio; AE=adverse event; ANC=absolute neutrophil count; 
GSK=GlaxoSmithKline; IRR=infusion-related reaction; NCI-CTCAE=National Cancer Institute Common 
Terminology Criteria for Adverse Events; PD=progressive disease; SoA=Schedule of Activities; ULN=upper limit 
of normal. 
a. 
If symptoms resolve within 1 hour of stopping infusion, the infusion may be restarted at half of the original 
infusion rate (e.g., from 100 mL/hr to 50 mL/hr). Otherwise, treatment with belantamab mafodotin must be held 
until symptoms resolve and the participant must be pre-medicated for the next scheduled dose. 
Table 11 
General Dose Modification and Management Guidelines for 
Belantamab Mafodotin-Related AEs Not Otherwise Specifieda 
Severity Management 
Follow-Up 
Grade 1 
• 
Administer symptomatic 
treatment as 
appropriate 
• 
Continue treatment with 
belantamab mafodotina 
• 
Provide close follow-up to evaluate for increased severity 
• 
No dose modification necessary 
Grade 2 
• 
Administer symptomatic 
treatment as 
appropriate 
• 
Investigate etiology 
• 
Consider consulting 
subspecialist and/or a 
diagnostic procedure 
Symptoms resolved in ≤7 days: 
• 
Continue treatment with belantamab mafodotin at the 
current dose after resolution 
Symptoms ongoing >7 days or worsening: 
• 
Withhold treatment with belantamab mafodotinb or 
consider dose reduction 
• 
If resolution takes >3 weeks, consult GSK Medical 
Director 
• 
If symptoms continue or worsen to Grade 3-4, see below 
Grade 3 
• 
Provide appropriate 
medical treatment 
• 
Consider Consulting 
subspecialist 
• 
Delay treatment until resolution to Grade ≤1 
• 
Consider dose reduction 
• 
Consider consultation with GSK Medical Director 
• 
Exception: Participants who develop Grade 3 toxicities 
which respond to standard medical treatment and 
resolve to Grade ≤1 within 48 h may continue treatment 
at current or reduced dose 
Grade 4 
• 
Provide appropriate 
medical treatment 
• 
Consider consulting 
subspecialist 
• 
Discuss with GSK 
medical director 
• 
Withhold treatment with belantamab mafodotin 
• 
Further treatment with belantamab mafodotin only 
allowed on individual basis if, in discussion with GSK 
Medical Director, it is agreed that benefits outweigh the 
risks for a given participant 
Abbreviations: AE=adverse event; GSK=GlaxoSmithKline. 
a. 
Treatment-related decisions can be made based on local laboratory results if central laboratory results are not 
available or are delayed. 

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b. 
In case a dose is delayed, the participant should wait for the next scheduled dose to resume treatment. 
6.5.4. 
Management of and Dose Modification for Participants with 
Hepatitis B Virus 
• 
Cases of HBV are required to be managed by local hepatology or infectious disease 
services. If no subspecialist support is available, consultation with the GSK Medical 
Director is required before enrolling participants with positive HBV titers into the 
study. 
• 
Participants with HBV should be monitored according to the SoA (Section 1.3). 
• 
For participants who experience clinically significant elevations in liver chemistry, 
follow the liver event monitoring and stopping criteria (Section 7.1.1 and 
Section 10.6) and immediately evaluate the etiology, including HBV 
deoxyribonucleic acid (DNA) testing. 
Dose modification guidelines for participants with a history of HBV who experience a 
reactivation of the virus (detectable HBV DNA levels) while on study treatment are 
provided in Table 12. 
Table 12 
Dose Modification Guidelines for HBV Reactivation 
Toxicity 
Grade/Description of 
Toxicity 
Recommendations 
HBV 
reactivation 
Detectable HBV DNA 
• 
Immediately (1 week) consult with local 
specialist(s) for case review and to start or 
modify HBV therapy and monitoring 
• 
Withhold treatment with belantamab 
mafodotin 
• 
Promptly contact the GSK Medical Director. 
Further treatment with belantamab mafodotin is 
only allowed if agreed by the GSK Medical 
Director. 
• 
Follow liver event monitoring and stopping 
criteria per protocol for elevation in liver function 
tests (Section 7.1.1 and Section 10.6). 
Abbreviations: DNA=deoxyribonucleic acid; GSK=GlaxoSmithKline; HBV=hepatitis B virus. 
6.6. 
Continued Access to Study Treatment after the End of the 
Study 
Study participants who continue to benefit from study intervention beyond the final data 
cutoff will continue to have access to study intervention until the EOS as defined in 
Section 4.6. There is no planned intervention following the EOS. 
The investigator is responsible for ensuring that consideration has been given to the post-
study care of the participant’s medical condition. 
Refer to the SoA (Table 1) for follow-up assessments of participants who are to be 
followed for disease progression and survival after they permanently discontinue from 

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study treatment until the final data cutoff date and to Section 4.6 for follow-up 
assessments from the final data cutoff date to the EOS. 
6.6.1. 
Continued Access to Study Treatment After the Final Data Cutoff 
prior to End of the Study 
Participants receiving belantamab mafodotin following 15 months after LSFD, (i.e., after 
the final data cut-off; see Section 4.6) may continue to receive belantamab mafodotin, if 
in the opinion of their treating physician, they are continuing to derive clinical benefit 
from continued treatment. Study treatment will continue until a study discontinuation 
criterion (see Section 7), as assessed by the investigator, has been met. 
DREAMM-14 study may move into a PACT phase where the study remains open only to 
provide continued access to treatment for study participants who are continuing to derive 
clinical benefit, and/or will continue to receive treatment via a managed access 
program/drug supply program. 
Participants who continue study treatment in the PACT phase receive care in accordance 
with local standard clinical practice, and will continue to be monitored for all SAEs, AEs 
leading to treatment discontinuation, overdoses and pregnancy cases and pre-specified 
ocular data while receiving belantamab mafodotin in the PACT phase. Information 
relating to participant care will be recorded on participant medical records, with the 
exception of SAEs, AEs leading to treatment discontinuation, overdoses and pregnancy 
cases and pre-specified ocular data that must continue to be reported to GSK for 
aggregate safety reporting but will not be reported as a part of this study. Investigators 
will report all SAEs, AEs leading to treatment discontinuation, overdoses, and pregnancy 
cases until 70 days after a participant receives their last dose of study drug in accordance 
with Section 8.4. Pre-specified ocular data will be reported until resolution, unless the 
event is considered by the investigator to be unlikely to resolve or the participant is lost to 
follow-up. After the final data cut-off, recording and follow-up of SAEs, AEs leading to 
treatment discontinuation, overdoses, pregnancy cases, and pre-specified ocular data will 
be done via paper forms (see SRM for details). Additionally, drug accountability data 
will also be collected at the site and assessments will revert to the standard of care at a 
participant’s particular site. 
6.7. 
Treatment of Overdose 
There is no specific information on overdose of belantamab mafodotin. GSK does not 
recommend specific treatment for an overdose of belantamab mafodotin. In the event of 
an overdose (defined as administration of more than the protocol-specified dose) of 
belantamab mafodotin, the investigator should: 
• 
Contact the GSK Medical Director immediately. 
• 
Evaluate the participant to determine, in consultation with the GSK Medical 
Director, if possible, whether study intervention should be interrupted or whether the 
dose should be reduced. 

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• 
Closely monitor the participant for AEs, SAEs, and laboratory abnormalities until 
they are resolved and belantamab mafodotin concentrations are predicted to be 
within the anticipated range in absence of the overdose 
• 
Obtain an additional pharmacokinetic and serum sBCMA sample as soon as the 
overdose situation is recognized and contact the GSK Medical Director for further 
guidance with regards to additional sample collection (determined on a case-by-case 
basis) 
• 
Document the quantity of the excess dose as well as the duration of the overdosing 
in the eCRF 
Decisions regarding belantamab mafodotin or administration of standard of care agents 
after an overdose will be made by the investigator in consultation with the GSK Medical 
Director based on the clinical evaluation of the participant. 
6.8. 
Concomitant Therapy 
Participants should receive full supportive care during the study, including transfusions of 
blood products, growth factors, and treatment with antibiotics, anti-emetics, 
anti-diarrheals, and analgesics, as appropriate. 
While on study, a participant who is diagnosed with an unrelated malignancy that can be 
addressed by local therapy can remain on study, study treatment may be resumed after 
discussion with the GSK Medical Director.  The participant should continue to be 
followed for disease progression of multiple myeloma as per the SoA. 
Participants will be instructed to inform the investigator before starting any new 
medications from the time of first dose of study treatment until the EOT visit. Any 
concomitant medication (including over-the-counter or prescription medicines, vitamins, 
and/or herbal supplements) that the participant is receiving at the time of enrollment or 
receives during the study must be recorded in the eCRF along with the following details: 
• 
Reason for use 
• 
Dates of administration including start and end dates 
• 
Dosage information including dose and frequency 
The GSK Medical Director should be contacted if there are any questions regarding 
concomitant or prior therapy. 
If future changes are made to the list of permitted/prohibited medications, formal 
documentation will be provided by GSK and stored in the study file. The SRM will be 
updated to include this information. Any such changes will be communicated to the 
investigative sites in the form of a letter. 
6.8.1. 
Ocular Supportive Care: Guidelines and Prophylactic Measures 
Ocular adverse events, which commonly manifest as superficial microcystic keratopathy, 
have been observed with ADCs, including those conjugated to MMAF. 

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Further information regarding corneal events associated with belantamab mafodotin is 
found in Section 2.1 and Section 2.3.1; prophylactic measures are included in this 
section. See the SoA (Section 1.3) for guidance on required monitoring for corneal 
toxicity. 
Study sites must establish a close collaboration with a qualified eye care specialist such 
as an ophthalmologist or optometrist (for qualifications see Section 10.1) who will be 
responsible for assessing participants while they are on-study and managing participants 
who develop ocular symptoms or vision changes (see Table 8 for exceptions). 
Management of such participants must be performed in close communication with the 
GSK Medical Director and the site’s qualified eye care specialist. Participants will be 
assessed by a qualified eye care specialist such as an ophthalmologist or optometrist at 
screening/baseline in all arms. 
6.8.1.1. 
Eye Drops and Cooling Eye Masks 
Preservative-Free Artificial Tears 
Participants in Arms A to E will receive preservative-free lubricant eyedrops to be used 
4 to 8 times a day in each eye, starting on Day 1 of belantamab mafodotin until EOT. In 
the event of ocular symptoms (i.e., dry eyes), the use of artificial tears may be increased 
up to every 2 hours. 
Steroid Eye Drops 
Corticosteroid eye drops are not required as prophylaxis but participants in Arms A to E 
may use these therapeutically if clinically indicated per discretion of an eye care 
specialist. Allow 5 to 10 minutes between administration of artificial tears and steroid eye 
drops, if administered together. If steroid eye drops are deemed medically necessary and 
prescribed, intraocular pressure must be monitored if used for >7 days. 
A qualified eye care specialist (see Section 10.1) consult is required for all participants 
who develop signs or symptoms of corneal events or require steroid eye drops for 
>7 days. 
Cooling Eye Masks 
While not yet clinically demonstrated, it is theoretically possible the application of a 
cooling eye mask during belantamab mafodotin administration, and in the first few hours 
after infusion, may decrease ocular side effects. Cooling eye masks may be applied to 
both eyes for as long as tolerated, up to 4 hours. 
6.8.2. 
Prohibited Medications and Non-Drug Therapies 
Chronic treatment with oral steroids is prohibited while a participant is on study. 
However, short-term (7 days) use of oral or intravenous steroids is allowed on study to 
manage acute complications related to study treatment (e.g., as prophylaxis and/or 
treatment of an IRR) or to treat exacerbations of chronic conditions or to manage an AE. 
Use of inhaled steroids is allowed on study to treat exacerbations of asthma or chronic 

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obstructive pulmonary disease. Chronic low-dose replacement therapy (10 mg/day 
prednisolone) is allowed on study for participants with adrenal insufficiency. 
Administration of live or live-attenuated vaccines is contraindicated 30 days before the 
first dose of study treatment and while receiving study treatment. Use of live or 
live-attenuated vaccines is further contraindicated for at least 70 days after the last dose 
of belantamab mafodotin. Killed or inactivated vaccines may be administered, however, 
the response to such vaccines cannot be predicted. 
Other prohibited therapies include the following: 
• 
Plasmapheresis: prohibited 7 days before the first dose of study treatment through 
the end of study 
• 
Any other approved or investigational anti-myeloma therapy not specified in this 
protocol (including but not limited to immunomodulatory and anti-neoplastic drugs 
or proteasome inhibitors). This is inclusive of all medications with activity against 
multiple myeloma and medications used for other indications that have 
anti-myeloma properties. 
• 
Any investigational agents other than belantamab mafodotin 
Caution should be exercised when belantamab mafodotin is combined with strong 
inhibitors of P-gp. 
Drugs that are OATP1B1/1B3 inhibitors, including the following anti-HIV and 
antimicrobial drugs, are prohibited unless considered medically necessary: 
• 
Anti-HIV drugs: atazanavir, lopinavir, nelfinavir, ritonavir, saquinavir, tipranavir 
• 
Anti-hepatitis C virus drugs: simeprevir, telaprevir 
• 
Antibiotics: clarithromycin, erythromycin, rifampin/rifampicin 
• 
Antifungals: itraconazole 
• 
Others: cyclosporine, eltrombopag, gemfibrozil 
Whenever possible, preferred alternative anti-HIV drugs and antimicrobials should be 
prescribed to participants who require these therapies. 
See the SRM for more detailed information and a full list of prohibited concomitant 
medications. 

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7. 
DISCONTINUATION OF STUDY TREATMENT AND 
PARTICIPANT DISCONTINUATION/WITHDRAWAL 
Discontinuation of specific sites or of the study as a whole is detailed in Section 10.10.9.  
7.1. 
Discontinuation of Study Treatment 
Participants will receive study treatment until confirmed disease progression per IMWG 
criteria [Kumar, 2016], unacceptable toxicity (including meeting stopping criteria for 
liver chemistry defined in Section 7.1.1), or death. 
Study treatment must be permanently discontinued for any of the following reasons: 
• 
Disease progression, as defined by IMWG criteria [Kumar, 2016], or unacceptable 
toxicity 
• 
Participant has met any of the protocol-defined safety stopping criteria 
• 
Pregnancy 
In addition, study treatment may be permanently discontinued for any of the following 
reasons: 
• 
Deviation(s) from the protocol 
• 
Request of the participant or proxy (withdrawal of consent by participant or proxy) 
• 
Investigator’s discretion 
• 
Participant is lost to follow-up 
• 
All or part of the study is closed or terminated 
The primary reason study treatment was permanently discontinued must be documented 
in the participant’s medical records and eCRF. 
If the participant voluntarily discontinues from treatment due to toxicity, AE must be 
recorded as the primary reason for permanent discontinuation on the eCRF. 
Once a participant has permanently discontinued from study treatment, the participant 
will continue to be followed until the end of study. 
All participants who permanently discontinue from study treatment for any reason other 
than confirmed progression or death will be followed up for PFS as specified in the SoA 
(see Section 1.3). 
Before discontinuing study treatment strictly due to disease progression, sites should 
contact the GSK Medical Director to confirm progression meets IMWG criteria 
[Kumar, 2016]. The GSK Medical Director will review the central laboratory results as 
well as imaging results (if applicable) to confirm progressive disease as per IMWG 
criteria. If progressive disease criteria are not met, the investigator retains the decision to 
determine if treatment should be discontinued. However, the reason for treatment 

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discontinuation should only be documented as disease progression if IMWG criteria for 
confirmed progressive disease are met.  
Note: Confirmation for progressive disease require two consecutive central laboratory 
assessments if there is no known evidence of radiographic PD; or an imaging assessment 
confirming new bone lesions, definite progression of existing, or development of new, 
extramedullary plasmacytomas (as per IMWG criteria [Kumar, 2016]) if radiographic 
studies were performed. 
Once a participant has permanently discontinued study treatment, the participant will not 
be allowed to restart study treatment. 
All participants who discontinue from study treatment will have safety assessments at the 
time of discontinuation and EOT follow-up according to the SoA (Section 1.3). 
Post-Treatment Follow-Up 
All participants who permanently discontinue study treatment in the absence of PD will 
remain in the study and will be followed for progression according to the protocol 
schedule until one of the following occurs (whichever comes first): 
• PD according to IMWG criteria 
• New anti-myeloma therapy initiated 
• Withdrawal of consent 
• Loss to follow-up 
• End of study (as described in Section 4.6.) 
• Death 
OS Follow-Up 
All participants who permanently discontinue study treatment and have experienced PD 
or have started new anti-myeloma therapy will remain in the study and will be followed 
for survival and subsequent anti-myeloma therapy until one of the following occurs 
(whichever comes first): 
• Withdrawal of consent 
• Loss to follow-up 
• End of study (as described in Section 4.6) 
• Death 
7.1.1. 
Liver Chemistry Stopping Criteria 
Liver chemistry stopping and increased monitoring criteria have been designed to 
assure participant safety and evaluate liver event etiology. 

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Discontinuation of study treatment for abnormal liver tests is required when either of the 
following situations occur: 
• 
A participant meets one of the conditions outlined in the liver chemistry stopping 
and increased monitoring algorithm (Figure 3), or 
• 
In the presence of abnormal liver chemistry not meeting protocol-specified stopping 
rules, if the investigator believes that it is in the best interest of the participant. 
Figure 3 
Liver Chemistry Stopping and Increased Monitoring Algorithm 
 
Abbreviations: ALT=alanine aminotransferase; INR=international normalized ratio; SAE=serious adverse event; 
tbili=total bilirubin; ULN=upper limit of normal. 
Refer to Section 10.6 for required liver safety actions, monitoring, and follow-up to 
assess the causality of liver events and to Section 10.12 for required process for study 
treatment restart/rechallenge if considered for a participant. 
Participants who do not meet protocol-specified liver event stopping criteria but meet 
protocol-defined increased monitoring criteria may continue to receive study intervention 
with increased (i.e., weekly) liver chemistry monitoring. Refer to Section 10.6 for details 
regarding required increased monitoring of liver chemistry with continued study 
intervention. 
7.1.2. 
Corneal Event Stopping Criteria 
For participants in Arms A to D, dose modifications and stopping criteria for corneal 
events should be based on grading corneal events according to the KVA scale for corneal 

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toxicities (see Table 8). For participants in Arm E, refer to Section 6.5.2 (dose 
modifications) and Section 9.2.2 (safety stopping rule for unacceptable ocular toxicity). 
Participants who develop Grade 4 corneal events according to the KVA scale must be 
discussed in detail with the treating qualified eye care specialist (as defined in 
Section 10.1), the GSK Medical Director, and, possibly, a third party ophthalmologist in 
order to determine whether the participant can be allowed to restart treatment with 
belantamab mafodotin or whether belantamab mafodotin should be permanently 
discontinued (Table 8). The decision will be documented in study files, together with 
individual assessment of benefit/risk. 
7.1.3. 
Infusion-Related Reaction Management and Stopping Criteria 
Premedication is not required before infusion unless deemed medically appropriate by the 
investigator after evaluation of IRRs. Premedication should be considered in any 
participant who experienced an IRR at the first or any subsequent infusion with 
belantamab mafodotin. 
For full details regarding the management of IRRs during infusion with belantamab 
mafodotin, see Table 10. For IRRs of any grade/severity, immediately interrupt the 
belantamab mafodotin infusion and manage symptoms. Once reaction symptoms resolve, 
resume the infusion at a reduced rate. Premedication may be required with subsequent 
infusions. 
A participant that experiences a Grade 4 IRR associated with belantamab mafodotin 
should be permanently withdrawn from the study. 
7.1.4. 
Allergic and Anaphylactic Reaction Stopping Criteria 
All participants will be monitored carefully for evidence of allergic response. A 
participant that exhibits signs or symptoms of severe hypersensitivity or anaphylaxis will 
receive appropriate medical treatment and must permanently discontinue study treatment. 
7.1.5. 
Rechallenge 
If a participant meets liver chemistry stopping criteria, do not restart/rechallenge the 
participant with study treatment unless all of the following criteria are met: 
• 
GSK approval is granted, and 
• 
Institutional Review Board (IRB) and/or Independent Ethics Committee (IEC) 
approval is obtained, if required, and 
• 
Separate consent for study treatment restart/rechallenge is signed by the participant 
and the participant is informed of any associated risks. 
• 
Refer to Section 10.12 for details on the restart/rechallenge process. 
If GSK approval to restart/rechallenge the participant with study treatment is not 
granted, then the participant must permanently discontinue study treatment and may 
continue in the study for protocol-specified follow-up assessments. 

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7.2. 
Participant Discontinuation/Withdrawal from the clinical 
Study 
• 
A participant may withdraw from the study at any time at his/her own request or 
may be withdrawn at any time at the discretion of the investigator for safety, 
behavioral, or compliance reasons. This is expected to be uncommon. 
• 
Investigators will attempt to contact participants who do not return for scheduled 
visits or follow-up. 
• 
At the time of discontinuing from the study, a discontinuation (EOT) visit should 
be conducted (Section 1.3). for data to be collected at the time of study 
discontinuation and follow-up and for any further evaluations that need to be 
completed. 
• 
After a participant withdraws or discontinues from the study, site personnel, or an 
independent third party, will attempt to collect the vital status of the participant 
within legal and ethical boundaries for all participants randomized, including those 
who did not get study treatment. Public sources may be searched for vital status 
information. If vital status is determined as deceased, this will be documented, and 
the participant will not be considered lost to follow-up. Sponsor personnel will not 
be involved in any attempts to collect vital status information. Upon the retrieval 
of vital status, site personnel will be responsible of entering data in EDC. 
• 
The participant will be permanently discontinued from the study treatment and the 
study at that time. 
• 
If the participant withdraws consent for disclosure of future information, the 
sponsor may retain and continue to use any data collected before such a 
withdrawal of consent. 
• 
If a participant withdraws from the study, he/she may request destruction of any 
samples taken and not tested, and the investigator must document this in the site 
study records. 
• 
Withdrawn participants who have received at least 1 dose of study treatment will 
not be replaced. 
The primary reason for participant withdrawal from the study will be documented in the 
eCRF based on what is described in Section 7.1. 
• 
Participants who are withdrawn from the study because of AEs/SAEs must be 
clearly distinguished from participants who are withdrawn for other reasons. 
Investigator will follow participants who are withdrawn from the study due to an 
AE/SAE until the event is resolved (see Section 10.14). 

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7.3. 
Lost to Follow-Up 
A participant will be considered lost to follow-up if they repeatedly fail to return for 
scheduled visits and are unable to be contacted by the study site. 
The following actions must be taken if a participant fails to return to the clinic for a 
required study visit: 
• 
The site must attempt to contact the participant and reschedule the missed visit as 
soon as possible, counsel the participant on the importance of maintaining the 
assigned visit schedule, and ascertain whether the participant wishes to and/or 
should continue in the study. 
• 
Before a participant is deemed lost to follow-up, the investigator or designee must 
make every effort to regain contact with the participant (where possible, 
3 telephone calls and, if necessary, a certified letter to the participant’s last known 
mailing address or local equivalent methods). These contact attempts should be 
documented in the participant’s medical record. 
• 
Should the participant continue to be unreachable, he/she will be considered to 
have withdrawn from the study. 
• 
Site personnel, or an independent third party, will attempt to collect the vital status 
of the participant within legal and ethical boundaries for all participants 
randomized, including those who did not get study treatment. Public sources may 
be searched for vital status information. If vital status is determined as deceased, 
this will be documented, and the participant will not be considered lost to 
follow-up. Sponsor personnel will not be involved in any attempts to collect vital 
status information. 

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8. 
STUDY ASSESSMENTS AND PROCEDURES 
8.1. 
Administrative and general procedures 
• 
Study procedures and their timing are summarized in the SoA (Section 1.3). 
• 
Protocol waivers or exemptions are not allowed. 
• 
Immediate safety concerns should be discussed with the sponsor immediately upon 
occurrence or awareness to determine if the participant should continue or 
discontinue study treatment. 
• 
Adherence to the study design requirements, including those specified in the SoA, is 
essential and required for study conduct. 
• 
All screening evaluations must be completed and reviewed to confirm that potential 
participants meet all eligibility criteria. Participants who have signed informed 
consent but are not eligible to proceed should be recorded in the eCRF with a status 
of “screen failure”. 
• 
Procedures conducted as part of the participant’s routine clinical management (e.g., 
blood count) and obtained before signing of ICF may be utilized for screening or 
baseline purposes provided the procedures met the protocol-specified criteria and 
were performed within the time frame defined in the SoA. 
• 
Demographic and baseline assessments will include year of birth, sex, race, and 
ethnicity. 
• 
Medical/medication/family history will be assessed as related to the eligibility 
criteria listed in Section 5. 
• 
Survival follow-up can be conducted by chart review, telephone call, or any other 
form of communication as laid out in the SoA. 
• 
Visit windows: 
o Baseline disease assessments must be completed 28 days before the date of 
randomization unless otherwise specified. 
o Screening assessments performed within the permitted time do not need to be 
repeated on Cycle 1 Day 1 unless otherwise specified. 
o Safety laboratory assessments completed within 72 hours of first dose do not need 
to be repeated on Cycle 1 Day 1. 
o Imaging must be completed 28 days before the date of randomization. 
o On-study Q3W and Q6W assessments have a ±3-day window. 
o After Cycle 1 Day 1, on-study ocular examinations should be performed 5 days 
before dosing. If the participant is not being dosed, ocular examinations may be 
performed within 3 days of the Q3W visit. 
o EOT visits have +30 day window. 
o OS follow-up visits have a ±14-day window. 

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8.2. 
Efficacy Assessments 
The following efficacy endpoints will be evaluated in all participants in the study: 
• 
ORR, defined as the percentage of participants with a confirmed PR or better (i.e., 
PR, VGPR, CR, and sCR) 
• 
Percentage of participants with a confirmed VGPR or better (i.e., VGPR, CR, and 
sCR) 
• 
Time to response (TTR), defined as the time between the date of randomization and 
the first documented evidence of response (PR or better), among participants who 
achieve a response (i.e., confirmed PR or better) 
• 
DoR in responders, defined as the time from first documented evidence of PR or 
better until PD or death due to any cause 
• 
Time to progression (TTP), defined as the time from randomization until the earliest 
date of documented PD or death due to PD 
• 
PFS, defined as the time from randomization until the earliest date of documented 
PD or death due to any cause 
• 
OS, defined as the time from randomization until the date of death due to any cause 
Efficacy assessments and/or diagnostic criteria will be evaluated during treatment by 
current practice guidelines for the management of RRMM [Anderson, 2016; 
Kumar, 2016; Moreau, 2017; Rajkumar, 2016]. These may include: 
• 
Laboratory tests 
o Urine protein electrophoresis (on 24 hour urine collection) and urine 
immunofixation for urine M protein assessment 
o Serum protein electrophoresis and serum immunofixation for Serum M protein 
assessment 
o Serum kappa, lambda FLC, FLC ratio 
o IgG, IgM, IgA 
o IgD, IgE (only in participants with IgD/E myeloma) 
o Calcium corrected for albumin 
• 
Bone marrow (BM) aspirate and/or biopsy at screening and to confirm CR/sCR. 
Additional BM testing if CR is achieved: biopsy for immunohistochemistry to 
confirm sCR.  
• 
Skeletal survey at screening as clinically indicated 
• 
Imaging for extramedullary disease (EMD) (in participants with EMD) and skeletal 
survey 
• 
Physical examination (as indicated for palpable/superficial lesions) 

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All efficacy assessments must be performed on a calendar schedule and must not be 
affected by dose interruptions/delays. For post-baseline assessments, a window of 
±3 days is permitted to allow for flexible scheduling. 
For participants who are discontinuing study treatment due to PD, the confirmation of PD 
is based on two central laboratory assessments (by 2016 IMWG response criteria 
[Kumar, 2016]) performed from a different blood collection either on the same day or, if 
possible, within 14 days of the original date of suspected PD, preferably before institution 
of any new anti-myeloma therapy. If the last imaging assessment was 8 weeks before 
the participant’s discontinuation from study treatment and PD has not been documented, 
a new disease assessment must be obtained at the time of discontinuation. For 
participants with PD due to EMD, confirmatory scans are not required. The laboratory 
parameters do not need to be repeated if the EMD is the only site of progression. 
8.2.1. 
Response Evaluation 
Clinical response assessments for RRMM will be evaluated as defined by 2016 IMWG 
response criteria [Kumar, 2016], as data permits, and assessed by the investigator.  
8.3. 
Safety Assessments 
Study safety assessments and their timing are summarized in the SoA (Section 1.3). 
8.3.1. 
Physical Examinations 
• 
A complete physical examination will include assessments of the cardiovascular, 
respiratory, gastrointestinal, and neurological systems. Height and weight will also 
be measured and recorded. (Note: Body weight at Cycle 1 Day 1 [before dosing] will 
be used for dose calculation of belantamab mafodotin. See Section 6.1.1 for 
guidance on belantamab mafodotin dosing if weight change is observed after C1D1). 
• 
Investigators should pay special attention to clinical signs related to previous serious 
illnesses. 
8.3.2. 
Vital Signs 
Vital sign measurements to be measured after 5 minutes rest and will include systolic and 
diastolic blood pressure, heart rate, and temperature. 
On Cycle 1 Day 1 (first infusion) dosing day, vital signs must be assessed at pre-dose 
(within 30 minutes before the start of infusion), within 15 minutes after end of infusion, 
and 1 hour post-end of infusion. On subsequent dosing days, vital signs must be assessed 
at pre-dose (within 30 minutes before the start of infusion) and within 15 minutes after 
end of infusion. 
On days where vital sign time points align with blood sampling time points, vital signs 
should be assessed before blood samples are drawn. 
On days where vital signs are measured multiple times, temperature does not need to be 
repeated unless clinically indicated. 

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In general, participants must also be monitored for at least 1 hour after the completion of 
the infusion of belantamab mafodotin and may be discharged if considered clinically 
stable and all other study procedures have been completed. 
In case of IRRs monitoring will be performed with higher frequency (as clinically 
indicated). 
8.3.3. 
Electrocardiograms 
A 12-lead ECG is obtained at screening. The ECG machine should automatically 
calculate the heart rate and measure PR, QRS, QT, and QTc intervals according to 
Fridericia’s formula. No further ECGs are required, but, if obtained as part of medical 
care, a 12-lead ECG should be performed by qualified personnel at the site after the 
participant has at least a 5-minute rest. 
8.3.4. 
Eastern Cooperative Oncology Group Performance Status 
The participant’s performance status will be assessed using the ECOG scale (see 
Section 10.8). 
8.3.5. 
Ocular Examinations 
Study sites must establish a close collaboration with a qualified eye care specialist such 
as an ophthalmologist or optometrist (for qualifications see Section 10.1) who will be 
responsible for assessing participants while they are on-study and managing participants 
who develop ocular symptoms or vision changes (see Table 8 for exceptions). 
Management of such participants must be performed in close communication with the 
GSK Medical Director and the site’s qualified eye care specialist. Participants will be 
assessed by a qualified eye care specialist such as an ophthalmologist or optometrist at 
screening/baseline in all arms. 
On-treatment ocular exams are to be performed Q3W, up to 5 days before dosing, from 
Cycle 2 onwards. If the participant is not being dosed, ocular examinations may be 
performed within 3 days of the Q3W visit. If a participant develops vision changes or 
other ocular symptoms, the participant should be promptly evaluated by a qualified eye 
care specialist such as an ophthalmologist or optometrist (as defined in Section 10.1). In 
case of persistent ocular examination findings, newly developed ocular symptoms, or 
vision changes, the participants will have further exams until resolution (to Grade 1 or 
baseline), or more frequently as clinically indicated by the qualified eye care specialist. 
If steroid eye drops are deemed medically necessary and prescribed, intraocular pressure 
must be monitored if used for >7 days. 
Participants with corneal events per the KVA scale (Grade 2 or higher) at the EOT visit 
will be followed by a qualified eye care specialist until full resolution of ophthalmic 
changes (Grade 1 or better) or start a new anti‑myeloma therapy, or up to 1 year 
(whichever comes first). 

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If the participant is in PFS follow-up, ocular assessments must be performed Q3W 
±3 days. If participant is in OS follow-up, ocular assessments must be performed Q12W 
±14 days. Additional examinations can be performed at the discretion of the eye care 
specialist and/or investigator. 
8.3.5.1. 
Ocular Examinations and Procedures (Eye Care Specialist’s Office, 
ALL Arms) 
A full screening/baseline ophthalmic examination for all participants (Arms A to E) 
must include the following assessments for both eyes (OU): 
1. Best corrected visual acuity (BCVA) 
2. Documentation of manifest refraction and the method used to obtain BCVA 
3. Current glasses prescription (if applicable) 
4. Anterior segment (slit lamp) examination with focus on the cornea and lens, 
including fluorescein staining of the cornea 
5. Tonometry (intraocular pressure measurement) 
6. Dilated funduscopic examination 
The on-treatment and follow-up ophthalmic examinations for all participants (Arms A 
to E) should include the following assessments for OU and will occur according to the 
SoA (Section 1.3): 
1. BCVA 
2. Documentation of manifest refraction and the method used to obtain BCVA 
3. Anterior segment (slit lamp) examination with focus on the cornea and lens, 
including fluorescein staining of the cornea 
4. Intraocular pressure measurement (if clinically indicated) 
5. Dilated fundoscopic examination (if clinically indicated) 
The EOT and last follow-up ophthalmic examination, if required, should match the 
screening/baseline examination. 
Additional examinations should be performed at the discretion of the qualified eye care 
specialist. 
8.3.5.2. 
Ocular Examinations and Procedures (Oncologist’s Office, Arm E 
ONLY) 
After ocular assessments by an eye care specialist (see Section 8.3.5.1), participants in 
Arm E will also undergo a visual acuity assessment in the oncologist’s office (according 
to the SoA [Section 1.3]), in order to determine dose modification decisions per 
Section 6.5.2. 

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8.3.6. 
Clinical Safety Laboratory Tests 
• 
See Section 10.13 for the list of clinical laboratory tests to be performed and the 
SoA (Section 1.3) for the timing and frequency. 
• 
The investigator must review the laboratory report, document this review, and 
record any clinically significant changes occurring during the study as an AE. The 
laboratory reports must be filed with the source documents. 
• 
All laboratory tests with values considered clinically significantly abnormal during 
participation in the study or within 70 days after the last dose of study treatment 
should be repeated until the values return to normal or baseline or are no longer 
considered significantly abnormal by the investigator or GSK Medical Director. 
• 
In the absence of a diagnosis, abnormal laboratory findings assessments or other 
abnormal results the investigator considers clinically significant will be recorded 
as an AE or SAE, if they meet the definition of an AE or SAE (refer to Section 
10.14.1 and Section 10.14.2). 
• 
If clinically significant values do not return to normal/baseline within a period of 
time judged reasonable by the investigator, the etiology should be identified and 
the sponsor notified. 
• 
Abnormal laboratory findings associated with the underlying disease are not 
considered clinically significant, unless judged by the investigator to be more 
severe than expected for the participant’s condition. 
• 
All protocol-required laboratory tests, as defined in Section 10.13, must be 
conducted in accordance with the Laboratory Manual and the SoA (Section 1.3). 
• 
Local laboratory results may be used to make decisions regarding treatment or 
management of AEs. If laboratory values from non-protocol-specified laboratory 
tests performed at the institution’s local laboratory require a change in participant 
management or are considered clinically significant by the investigator (e.g., 
AE/SAE or dose modification), then the results must be recorded. 
• 
Details for the preparation and shipment of samples for central laboratory 
assessments are provided in the Laboratory Manual. Also refer to the Laboratory 
Manual for appropriate processing and handling of samples to avoid duplicate 
and/or additional blood draws. 
• 
Before administration of the first dose of study treatment, results of laboratory 
assessments should be reviewed. Any laboratory test with a value outside the 
normal range may be repeated (before the first dose) at the discretion of the 
investigator. 
8.3.7. 
Pregnancy Testing 
• 
Refer to Section 5.1 for pregnancy testing entry criteria. 
• 
Serum pregnancy testing should be performed at screening in WOCBP, only. The 
first test should be performed within 10 to 14 days before the first dose and the 
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questionable cases (child-bearing status), follicle-stimulating hormone and estradiol 
(as needed in WONCPB potential only) should be performed at local laboratory. 
• 
Pregnancy testing after screening and Cycle 1 Day 1 may be either urine or serum 
(as required by local regulations) and must be performed with 72 hours before 
dosing. 
• 
Final pregnancy testing may be either urine or serum (as required by local 
regulations) and must be performed in WOCBP within 70 days after the last dose. 
Follow-up pregnancy assessment by telephone for WOCBP should be performed 
4 months after the last dose of study treatment. 
• 
Additional serum or urine pregnancy tests may be performed, as determined 
necessary by the investigator or required by local regulation, to establish the 
absence of pregnancy at any time during the participant’s participation in the study. 
8.3.8. 
Suicidal Ideation and Behavior Risk Monitoring 
Not applicable. 
8.4. 
Adverse Events, Serious Adverse Events, and Other Safety 
Reporting 
The definitions of an AE or SAE can be found in Section 10.14.1 and Section 10.14.2, 
respectively. 
AEs will be reported by the participant (or, when appropriate, by a caregiver, surrogate, 
or the participant’s legally authorized representative). 
The investigator and any qualified designees are responsible for detecting, documenting, 
and recording events that meet the definition of an AE or SAE and remain responsible for 
following-up AEs that are serious, considered related to the study treatment or the study, 
or that caused the participant to discontinue the study treatment (see Section 7.1). This 
includes events reported by the participant. 
The method of recording, evaluating, and assessing causality of AEs and SAEs and the 
procedures for completing and transmitting SAE reports are provided in Section 10.14.4 
and Section 10.14.5. 
8.4.1. 
Time Period and Frequency for Collecting Adverse Event and 
Serious Adverse Event Information 
• 
All AEs and SAEs will be collected from the start of study treatment until at least 
70 days after discontinuation of study treatment, regardless of initiation of a new 
anti-myeloma therapy or transfer to hospice, at the time points specified in the SoA 
(Section 1.3). However, any SAEs assessed as related to study participation (e.g., 
study treatment, protocol-mandated procedures, invasive tests, or change in existing 
therapy) will be recorded from the time a participant consents to participate in the 
study up to and including any follow-up. 

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• 
Medical occurrences that begin before the start of study treatment but after 
obtaining informed consent will be recorded as medical history/current medical 
conditions, not as AEs. 
• 
All SAEs will be recorded and reported to the sponsor or designee immediately and 
under no circumstance should this exceed 24 hours, as indicated in Section 10.14. 
The investigator will submit any updated SAE data to the sponsor within 24 hours 
of it being available. 
• 
A post-study AE/SAE is defined as any event that occurs outside of the AE/SAE 
reporting period defined in Table 13. 
• 
Investigators are not obligated to actively seek information on AEs or SAEs after 
the conclusion of study participation. However, if the investigator learns of any 
SAE, including a death, at any time after a participant has been discharged from the 
study, the investigator must record it in the medical records per the local country 
requirements. If the investigator considers the event to be reasonably related to the 
study treatment or study participation, the investigator must promptly notify the 
sponsor. 
• 
After the final data cutoff, participants still deriving clinical benefit in the opinion 
of their treating physician may continue to receive belantamab mafodotin in the 
PACT phase and/or will continue to receive treatment via a managed access 
program/drug supply program. 
For participants in the PACT phase of the study, GSK will continue to collect safety 
information including SAEs, AEs leading to treatment discontinuation, overdose and 
pregnancy cases and pre-specified ocular data via paper forms which will be reported 
directly to GSK (see SRM for details). SAEs, AEs leading to treatment discontinuation, 
overdose and pregnancy cases will be reported during the PACT treatment period and for 
up to 70 days after last dose and pre-specified ocular data will be reported until resolution 
unless the event is considered by the investigator to be unlikely to resolve, or the patient 
is lost to follow-up. Additionally, any SAEs that are ongoing at the time of the final data 
cutoff must be followed up to resolution unless the event is considered by the investigator 
unlikely to resolve, or the patient is lost to follow-up. Updates to these events will also 
occur via paper forms directly to GSK (see SRM for details). GSK retains the right to 
request additional information for any patient with ongoing AE(s)/SAE(s)/ocular events 
at EOS, if judged necessary.  
Ocular Follow-Up: 
For participants who continue to receive belantamab mafodotin as part of PACT:  
• 
Ocular exam schedule during PACT treatment: 
o Participants without ocular (including corneal) examinations findings, 
symptoms, or vision changes when entering the PACT phase will be required to 
have an ocular assessment at least every 12 weeks, or as clinically indicated, 
until the end of treatment. 
o For participants who at the time of entering PACT have ocular (including 
corneal) examinations findings, symptoms or vision changes (or develop these 
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(and prior to the next belantamab mafodotin infusion if dosing), until resolution 
(KVA Grade 1 or baseline). After resolution, the ocular exam assessment 
frequency reduces to at least every 12 weeks, or as clinically indicated, until the 
end of treatment. 
• 
Ocular exam schedule after end of PACT treatment: 
o It is advised that participants with treatment-related ocular examination findings 
at the end of the study continue to have ocular assessments as standard of care 
until resolution. Note that patients who continue to receive belantamab 
mafodotin via commercial source of a managed access program/drug supply 
program should follow ocular examination guidance provided by the 
source/program from which they are receiving belantamab mafodotin. 
o For participants without ocular (including corneal) examination findings, 
symptoms, or vision changes at the end of PACT treatment no further ocular 
exams are required. 
 
For participants who stopped belantamab mafodotin prior to PACT but have ongoing 
ocular events at the time of final study data cutoff/start of PACT:  
• 
Participants with treatment-related ocular (including corneal) examination findings, 
symptoms, or vision changes at the start of PACT have ocular assessments at least 
every 12 weeks for up to 12 months from the end of treatment or until resolution 
(KVA Grade 1 or baseline), or withdrawal of consent, whichever comes first. 
8.4.2. 
Method of Detecting Adverse Events and Serious Adverse Events 
Care will be taken not to introduce bias when detecting AEs and/or SAEs. Open-ended 
and nonleading verbal questioning of the participant is the preferred method to inquire 
about AE occurrence. 
8.4.3. 
Follow-up of Adverse Events and Serious Adverse Events 
After the initial AE/SAE report, the investigator is required to proactively follow each 
participant at subsequent visits/contacts. All SAEs, and non-AESIs (as defined in Section 
8.4.4), will be followed until the event is resolved, stabilized, otherwise explained, or the 
participant is lost to follow-up (as defined in Section 7.3). Further information on 
follow-up procedures is given in Section 10.14.4. 
8.4.4. 
Adverse Events of Special Interest 
AESIs for belantamab mafodotin are corneal events, thrombocytopenia, and IRRs. 
Severity of corneal events will be graded using the KVA scale (provided in Table 8). 
Severity of thrombocytopenia and IRRs will be graded using NCI-CTCAE Version 5.0. 
Guidelines for dose modifications and interruptions for management of common 
toxicities associated with the study treatment are provided in Section 6.5. 

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8.4.5. 
Regulatory reporting requirements for SAEs/AESIs 
• 
Prompt notification by the investigator to the sponsor of an SAE is essential so that 
legal obligations and ethical responsibilities toward the safety of participants and 
the safety of a study treatment under clinical investigation are met. 
• 
The sponsor has a legal responsibility to notify both the local regulatory authority 
and other regulatory agencies about the safety of a study treatment under clinical 
investigation. The sponsor will comply with country-specific regulatory 
requirements relating to safety reporting to the regulatory authority, IRBs/IECs, and 
investigators. 
• 
For SAEs/AESIs, the investigator must always provide an assessment of causality 
at the time of the initial report, as defined in the Section 10.3. 
• 
An investigator who receives an investigator safety report describing an SAE or 
other specific safety information (e.g., summary or listing of SAE) from the sponsor 
will review and then file it along with the Investigator’s Brochure and will notify 
the IRB/IEC, if appropriate according to local requirements. 
• 
Investigator safety reports must be prepared for suspected unexpected serious 
adverse reactions (SUSARs) according to local regulatory requirements and sponsor 
policy and forwarded to investigators as necessary. 
Table 13 
Timeframes for submitting SAE, pregnancy and other events reports 
to GSK  
Type of event 
Initial reports 
Follow-up of relevant information on a previous 
report 
Timeframe 
Documents 
Timeframe 
Documents 
SAEs 
24 hours* ‡ 
Paper/electronic AEs Report 
24 hours* 
Paper/electronic AEs Report 
Pregnancies  
24 hours* 
Paper pregnancy notification 
report/electronic pregnancy 
report  
24 hours * 
Paper pregnancy follow-up 
report/electronic pregnancy 
report  
AESIs  
24 hours** ‡ 
Paper/electronic AEs Report 
24 hours* 
Paper/electronic AEs Report 
AE = adverse event; AESI = adverse event of special interest; eCRF = electronic case report form; DRE = disease-
related event; PRE = population related event; SRT = Safety Review Team. 
* Timeframe allowed after receipt or awareness of the information by the investigator/site staff. 
**Timeframe allowed once the investigator determines that the event meets the protocol definition of an AESI  
‡ Paper AEs Report will be dated and signed by the investigator (or designee). For each SAE/AESI, the investigator(s) 
must document in the medical notes that they have reviewed the SAE/AESI and have provided an assessment of 
causality. 
8.4.6. 
Pregnancy 
• 
Details of all pregnancies in female participants will be collected after the start of 
study treatment and for 4 months after the last dose of study treatment. Details of all 
pregnancies in female partners of male participants will be collected after the start 
of study treatment and for 6 months after the last dose of study treatment. 
• 
If a pregnancy is reported, the investigator will record pregnancy information on the 
appropriate form and submit it to GSK within 24 hours of learning of the pregnancy 

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(first obtain the necessary signed informed consent from the female partner if the 
pregnancy occurs in the female partner of a male participant). While pregnancy 
itself is not considered to be an AE or SAE, any pregnancy complication or elective 
termination of a pregnancy for medical reasons will be reported as an AE or SAE. 
• 
Abnormal pregnancy outcomes (e.g., spontaneous abortion, fetal death, stillbirth, 
congenital anomalies, ectopic pregnancy) are considered SAEs and will be reported 
as such. 
• 
The pregnant participant/pregnant female partner will be followed to determine the 
outcome of the pregnancy. The investigator will collect follow-up information on 
the pregnant participant /pregnant female partner and the neonate for 6 to 8 weeks 
after delivery and the information will be forwarded to the sponsor. See Table 13 
for reporting timeframes. 
• 
Any post-study pregnancy-related SAE considered reasonably related to the study 
treatment by the investigator will be reported to the sponsor as described in 
Section 8.4.5. While the investigator is not obligated to actively seek this 
information in former female study participants/female partners of male 
participants, he or she may learn of an SAE through spontaneous reporting. 
• 
Any female participant who becomes pregnant while participating in the study must 
discontinue study treatment. 
8.4.7. 
Cardiovascular and Death Events 
For any cardiovascular events detailed in Section 10.14.3 and for all deaths, whether or 
not they are considered SAEs, specific Cardiovascular (CV) and Death sections of the 
eCRF will be required to be completed. These sections include questions regarding CV 
(including sudden cardiac death) and non-CV death. 
The CV eCRFs are presented as queries in response to reporting of certain CV MedDRA 
terms. The CV information should be recorded in the specific CV section of the CRF 
within 1 week of receipt of a CV Event data query prompting its completion. 
The Death eCRF is provided immediately after the occurrence or outcome of death is 
reported. Initial and follow-up reports regarding death must be completed within 1 week 
of when the death is reported. Record deaths due to the disease under study in the Death 
eCRF. Record deaths due to reasons other than the disease under study in the standard 
Death Details eCRF. 
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8.4.9. 
Medical device deficiencies 
Not applicable. 
8.5. 
Pharmacokinetics 
8.5.1. 
Blood Sample Collection for Pharmacokinetics 
Blood samples for pharmacokinetic analysis of belantamab mafodotin (ADC) and 
cys-mcMMAF will be collected for all participants at the time points indicated in the SoA 
(Section 1.3). Alterations may be made to the sampling schedule based on the results 
from analyses of emerging data. Such alterations, if made, will not require a protocol 
amendment and will be documented in the laboratory manual. 
Each pharmacokinetic sample should be collected as close as possible to the planned time 
relative to the administration of the drug being measured on pharmacokinetic sampling 
days. The actual date and time of each blood sample collection will be recorded. Details 
on pharmacokinetic blood sample collection including blood volumes, processing, 
storage, and shipping procedures are provided in the SRM. 
sBCMA samples should be collected at all pharmacokinetic time points as close as 
possible to the belantamab mafodotin pharmacokinetic sample. 
All pharmacokinetic, sBCMA, and ADA samples once collected can be analyzed if the 
sample date and time have been recorded. 
Pharmacokinetic and accompanying sBCMA sample collection may be terminated when 
sufficient data have been collected. 
8.5.2. 
Pharmacokinetic Sample Analysis 
Plasma pharmacokinetic sample analysis will be performed under the control of GSK. 
Concentrations of belantamab mafodotin and cys-mcMMAF will be determined in 
plasma samples using the currently approved bioanalytical methodology. The 
bioanalytical site will be detailed in the relevant sample processing documents (e.g., 
Central Laboratory Worksheet [CLW]) and raw data will be archived at the bioanalytical 
site for the specified portion of the retention period before being returned to the GSK 
archives for the reminder of the retention period. 
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8.6. 
Genetics 
A 6 mL blood sample for DNA isolation will be collected from participants who have 
consented to participate in the genetics analysis component of the study. Participation is 
optional. Participants who do not wish to participate in the genetic research may still 
participate in the study. 
In the event of DNA extraction failure, a replacement genetic blood sample may be 
requested from the participant. Signed informed consent will be required to obtain a 
replacement sample unless it was included in the original consent. 
Information regarding genetic research is included in Section 10.15. In approving the 
clinical protocol, the IRB/IEC and, where required, the applicable regulatory agency, are 
also approving the genetic research described unless otherwise indicated. Where required 
by regulatory authorities, approval of the genetic assessments can occur after approval is 
obtained for the rest of the study. In that case, written approval will indicate that approval 
of the genetic assessments is being deferred and the study, except for genetic 
assessments, can be initiated. If genetic assessments are not approved, they will not be 
conducted. 
8.7. 
Biomarkers/Translational Research 
Biomarker research is part of this study and will involve peripheral blood (serum and 
plasma), BM, and tumor biopsies. sBCMA and BCMA expression in tumor cells will be 
analyzed and the relationship of these biomarkers relative to response to belantamab 
mafodotin will be assessed. Additionally, any blood, serum, plasma, and BM samples 
collected during this study may be used to measure novel biomarkers to identify factors 
associated with the biological and clinical responses to belantamab mafodotin. If 
relevant, this approach may be extended to include the identification of biomarkers 
associated with AEs. Unless stated otherwise, these investigations may be performed 
irrespective of whether a response to belantamab mafodotin is observed. The novel 
biomarkers may involve DNA analysis, RNA analysis, cell analysis (T, B, and natural 
killer cells flow panel), and/or protein analysis. 
Samples will be collected at the time points indicated in the SoA (Section 1.3). The 
sample collection strategy may be adjusted on the basis of emerging data from this study 
or other studies involving belantamab mafodotin in order to ensure optimal evaluation of 
any potential biomarkers. Additionally, novel biomarkers may also be incorporated, as 
data warrant. These analyses may include but not be limited to: 
• 
BCMA expression by immunohistochemistry and/or DNA/RNA analysis performed 
on BM biopsies and/or aspirates 
• 
Measurements of the serum levels of sBCMA 
• 
Soluble factors 
• 
Parallel blood analyses that may evaluate effects on natural killer or other immune 
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8.7.1. 
Soluble B-Cell Maturation Antigen 
The BCMA receptor undergoes gamma-secretase mediated cleavage, leading to release 
of the BCMA extracellular domain as sBCMA into circulation [Laurent, 2015]. 
sBCMA will be measured in all treatment arms of this study. 
sBCMA samples should be collected at all pharmacokinetic time points for all 
participants, according the SoA (Section 1.3). 
Serum sBCMA sample analysis will be performed under the control of GSK using the 
currently approved analytical methodology. The bioanalytical site will be detailed in the 
relevant sample processing documents (e.g., CLW) and raw data will be archived at the 
analytical site for the specified portion of the retention period before being returned to the 
GSK archives for the reminder of the retention period. 
8.7.2. 
Tumor Biomarker Analysis 
While BCMA expression is present in all MM cells, there is some cell to cell variability 
and differences in membranous and cytosolic localization patterns. Therefore, it is 
important to determine if there is any association between the expression levels of 
BCMA on MM cells and clinical responses. BM samples will be collected during this 
study at the time points indicated in the SoA (Section 1.3). 
BCMA expression analysis to be performed preferably on a BM biopsy sample. Any 
remaining aspirate and/or biopsy sample will be used for biomarker research (which may 
include immune cell characterization and/or profiling and/or DNA/RNA analyses). 
8.7.3. 
RNA Transcriptome Research 
RNA expression studies may be conducted using RNA sequencing, quantitative reverse 
transcriptase-polymerase chain reaction and/or alternative equivalent technologies which 
can facilitate the simultaneous measurement of the relative abundances of RNA species 
resulting in an RNA expression profile for BM or other samples. The RNAs assayed may 
be those involved with the following: 
1. The pathogenesis of MM 
2. The absorption, distribution, metabolism, or excretion of belantamab mafodotin 
3. The participant’s response to belantamab mafodotin. 
In addition, continuing research may identify other proteins or regulatory RNAs that may 
be involved in the response to belantamab mafodotin or the pathogenesis of MM. The 
RNAs that code for these proteins and/or regulatory RNAs may also be studied. This 
would enable the evaluation of changes in RNA expression profiles that may correlate 
with biological responses relating to MM and the action of belantamab mafodotin. 
The samples may also be used to confirm findings by application of alternative 
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8.8. 
T, B, and Natural Killer Cells 
Whole blood will be collected and analyzed by flow cytometry for percentage and 
absolute counts of monocytes, T, B, and natural killer cells, as well as the expression of 
activation markers on these cell types to help inform on participant immune status. 
8.9. 
Immunogenicity Assessments 
Serum samples for the analysis of anti-belantamab mafodotin antibodies will be collected 
before each belantamab mafodotin infusion (at dose 1, 2, 4, 6, 9 and 12, see Table 4). 
These samples will be tested by the sponsor or sponsor’s designee. 
Anti-belantamab mafodotin antibody samples will be tested for anti-belantamab 
mafodotin antibodies using a tiered-testing scheme consisting of validated screening, 
confirmation, and titration assays. Briefly, all samples will be tested in the screening 
assay. Samples that screen positive are considered potentially positive and will be tested 
for specificity in a confirmation assay. Finally, titer values will be obtained for confirmed 
positive samples using a titration assay. The sample results (e.g., positive or negative) 
and titer values (positive samples only) will be reported. Samples that test positive for 
anti-belantamab mafodotin antibodies may be further characterized in a validated 
neutralizing antibody assay to determine the neutralizing activity of the antibodies. 
The detection and characterization of antibodies to belantamab mafodotin will be 
performed using validated assays. The anti-belantamab mafodotin antibody assay was 
designed to detect antibodies to belantamab mafodotin, the unconjugated monoclonal 
antibody, and the linker-payload portion of belantamab mafodotin. Anti-belantamab 
mafodotin antibody samples will be disposed 3 months after final approved results are 
provided to the clinical study team or its designee or upon documented study termination. 
Immunogenicity sample analysis will be performed under the control of GSK, using the 
currently approved analytical methodology. The analytical site will be detailed in the 
relevant sample processing documents (e.g., CLW) and raw data will be archived at the 
analytical site for the specified portion of the retention period before being returned to the 
GSK archives for the reminder of the retention period. 
Sample collection for immunogenicity (ADA) assessment may be terminated when 
sufficient data have been collected. 
8.10. 
Patient-Reported Outcomes 
PROs should be done at the start of the visit before any assessments and before any 
results are discussed. All participants will complete the self-administered version of each 
questionnaire, unless their vision or other factors prevents them from being able to 
complete the questionnaire on their own. Participants who are not able to complete the 
questionnaire on their own (e.g., vision problems) and so require assistance, should have 
the PROs administered to them in an interview-administered format. If the interviewer-
administered format is used, the questionnaires should be read to the participants 
verbatim, and participant responses should be recorded directly without any 
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participation in the treatment period or during follow-up), the interview-administered 
format should be used. 
The questionnaires will be administered to participants in different regions based on the 
availability of translated versions. For Arm E, in which dose modification decisions are 
informed by the results of the OSDI questionnaire, the OSDI must be available in the 
appropriate language in order for a participant to be randomized into this arm. 
8.10.1. 
Treatment and Tolerability-Related Patient-Reported Outcomes 
Three treatment-related PRO questionnaires will be performed in this study. More details 
about all participant questionnaires can be found in the SRM. 
8.10.1.1. 
Patient-Reported Outcomes version of the Common Terminology 
Criteria for Adverse Events (PRO-CTCAE) 
The PRO-CTCAE is a PRO measure developed to evaluate symptomatic toxicity in 
participants in oncology clinical studies [Basch, 2014]. The PRO-CTCAE was designed 
to be used as a companion to the CTCAE, the standard lexicon for AE reporting in 
oncology studies. The PRO-CTCAE includes an item library of 124 items representing 
78 symptomatic toxicities drawn from the CTCAE. The PRO-CTCAE provides a 
systematic yet flexible tool for descriptive reporting of symptomatic treatment side 
effects in oncology clinical studies. Up to 3 attributes are asked depending upon the 
relevance to the question, including frequency, severity, and interference with usual or 
daily activities. The recall period is “over the past 7 days”. In the present study, a 
selection of items from the PRO-CTCAE version 1.0 item library will be administered to 
participants. These items are mouth sores, problems tasting food, decreased appetite, 
nausea, vomiting, constipation, diarrhea, pain in abdomen, shortness of breath, cough, 
itchy skin, hives, numbness/tingling in hands or feet, blurry vision, flashing lights, 
floaters, watery eyes, fatigue/lack of energy, pain/burning with urination, bruising, chills, 
and nosebleeds. 
8.10.1.2. 
Ocular Surface Disease Index (OSDI) 
The OSDI is a 12-item questionnaire designed to assess both the frequency of dry eye 
symptoms and their impact on vision-related functioning [Dougherty, 2011; 
Schiffman, 2000]. The OSDI has demonstrated good reliability, validity, sensitivity, and 
specificity, and can be used as a complement to other clinical and participative measures 
of dry eye disease by providing a quantifiable assessment of dry eye symptom frequency 
and the impact of these symptoms on vision related functioning. The OSDI includes a 
Total Score and 3 domain scores of Ocular Symptoms (sensitivity to light, gritty eyes, 
painful or sore eyes, blurred vision, poor vision), Vision-Related Functioning (reading, 
driving at night, working on computer/ATM, watching TV) and Environmental Triggers 
(windy conditions, dry areas, air conditioning), with a recall period of “the last week”. 
The response options are based on frequency: “none of the time”, “some of the time”, 
“half of the time”, “most of the time”, and “all of the time”. 

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8.10.1.3. 
Functional Assessment of Cancer Therapy – General Population 
(FACT-GP5) 
The FACT-G (now in version 4) is a 27-item compilation of general questions divided 
into 4 primary quality of life domains: Physical Well-Being, Social/Family Well-Being, 
Emotional Well-Being, and Functional Well-Being [Cella, 1993]. It is considered 
appropriate for use with participants with any form of cancer and has also been used and 
validated in other chronic illness condition (for example, HIV/AIDS and multiple 
sclerosis) and in the general population (using a slightly modified version). 
The FACT-GP5 item is a single item from the FACT-G, which assesses how bothersome 
the side effects of treatment are for participants with cancer. The recall period is the past 
7 days, and the item has a 5 category response scale ranging from “0=Not at all” to 
“4=Very much”. This item is being included to assess the overall tolerability of treatment 
from the participant’s perspective. 
8.10.2. 
Health-Related Quality of Life 
Three HRQoL assessments will be performed in this study. More details about all 
participant questionnaires can be found in the SRM. 
8.10.2.1. 
European Organisation for Research and Treatment of Cancer Quality 
of Life Questionnaire 30-Item Core Module (EORTC-QLQ-C30) 
The EORTC-QLQ-C30 is a 30-item questionnaire containing both single- and multi-item 
measures [Aaronson, 1993]. These include 5 functional scales (Physical, Role, Cognitive, 
Emotional, and Social Functioning), 3 symptom scales (Fatigue, Pain, and 
Nausea/Vomiting), a Global Health Status/quality of life scale, and 6 single items 
(Constipation, Diarrhea, Insomnia, Dyspnea, Appetite Loss, and Financial Difficulties). 
Scores for each scale and single-item measure are averaged and transformed linearly to a 
score ranging from 0 to 100. A high score for functional scales and for Global Health 
Status/quality of life represent better functioning ability or HRQoL, whereas a high score 
for symptom scales and single items represents significant symptomatology 
[Proskorovsky, 2014]. 
8.10.2.2. 
European Organisation for Research and Treatment of Cancer Quality 
of Life Questionnaire 20-item Multiple Myeloma Module (EORTC-QLQ-
MY20) 
The EORTC-QLQ-MY20 is a supplement to the EORTC-QLQ-C30 instrument used in 
people with MM [Aaronson, 1993; Cocks, 2007]. The module comprises 20 questions 
that address four myeloma-specific HRQoL domains: Disease Symptoms, Side Effects of 
Treatment, Future Perspective, and Body Image. Three of the four QLQ-MY20 domains 
are multi-item scales: Disease Symptoms (includes bone aches or pain, back pain, hip 
pain, arm or shoulder pain, chest pain, and pain increasing with activity); Side Effects of 
Treatment (includes drowsiness, thirst, feeling ill, dry mouth, hair loss, upset by hair loss, 
tingling hands or feet, restlessness/agitation, acid indigestion/heartburn, and burning or 
sore eyes); and Future Perspective (includes worry about death and health in the future, 

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and thinking about illness). The Body Image scale is a single-item scale that addresses 
physical attractiveness. 
As with the EORTC-QLQ-C30, EORTC-QLQ-MY20 domain scores are averaged and 
transformed linearly to a score ranging from 0 to 100. A high score for Disease 
Symptoms represents a high level of symptomatology or problems [Proskorovsky, 2014]. 
8.10.2.3. 
Patient Global Impression Items 
The Patient Global Impression of Severity (PGIS) assesses global impression of 
symptoms severity at baseline and subsequent time points. The second question, the 
Patient Global Impression of Change (PGIC) serves to rate the global change in 
symptoms at subsequent time points. In addition to evaluating symptom severity and 
change, these questions serve as anchors to establish thresholds of clinically meaningful 
change for the questionnaires in the study [Guy, 1976]. 

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9. 
STATISTICAL CONSIDERATIONS AND DATA 
ANALYSES 
The primary focus of this study will be on identifying a dosing regimen with the potential 
to minimize the risk of ocular toxicity without a qualitatively clinically meaningful 
impact on efficacy, based upon the safety, clinical activity, and pharmacokinetic profiles. 
9.1. 
Statistical Hypothesis 
No formal hypothesis testing will be performed in this study. 
9.2. 
Sample Size Considerations  
Approximately 40 participants will be enrolled into Arms A [control], B, C, and D, each, 
and approximately 20 participants will be enrolled into Arm E (N=180). The sample size 
and associated operating characteristics were evaluated via simulations. 
An interim analysis is planned when approximately 15 participants each in Arms A to D 
have been enrolled and have received 2 doses of study treatment with 1 disease 
assessment following the second dose or confirmed PD per IMWG [Kumar, 2016] or 
death. Any arm in Arms B to D with ≤2 responders will be discontinued from further 
enrollment and arms with ≥3 responders will continue enrollment (see 
Section 9.5).Enrollment will continue as analysis is being performed. If Arm D is stopped 
due to futility, Arm E will also be stopped. If Arms B, C, D, or E are stopped due to 
futility, participants will be given the opportunity to switch to 2.5 mg/kg Q3W 
(Arm A/control regimen), provided the participant has not experienced PD; the data 
collected from participants after switching will not be included in the primary analysis 
and may be analyzed separately. 
Note: Enrolled means a participant’s, or their legally authorized representative’s, 
agreement to participate in a clinical study after completion of the informed consent 
process and screening. Potential participants who are screened for the purpose of 
determining eligibility for the study, but who do not participate in the study, are not 
considered enrolled, unless otherwise specified by the protocol. A participant will be 
considered enrolled if the informed consent is not withdrawn before participating in any 
study activity after screening. 
9.2.1. 
Sample Size Assumptions: Primary Endpoint 
Based on the Grade 2 incidence rate observed in the 95 participants in the 2.5 mg/kg 
Q3W arm of the DREAMM-2 study (based on the 20 September 2019 data cutoff date), 
the prior of the incidence rate in Arm A is assumed to follow a Beta (6.32, 3.68) 
distribution with a mean of 63.2% and an effective sample size of 10, which is 
down-weighted so that the prior is informative yet data to be collected in this study will 
still dominate the conclusion. The prior of those of Arms B to D are assumed to follow a 
Beta (0.41, 0.59) distribution with a mean of 41%, which corresponds to a 35% relative 
reduction from the incidence rate of 63.2%, and an effective sample size of 1. 

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The primary analysis will be performed at least 9 months after the first response of the 
last responder (i.e., PR, VGPR, CR, and sCR) or 12 months after the last participant is 
randomized into Arms A to D whichever comes first. 
The operating characteristics in Table 14 are summarized based on 40 participants per 
arm. The acceptance criterion is the posterior probability of the difference in incidence 
rates between the control and test arm being >0.17 is >0.7. The difference of 0.17 is 
chosen such that there is a reasonable chance of identifying an arm with improved safety 
in this study and the probability of falsely identifying an arm is well controlled. When the 
true incidence rates of Grade ≥2 are 63% and 40% in the control and test arms 
respectively, the probability of meeting acceptance criterion is 80%. When the true 
differences in incidence rates are 0, the probability of meeting acceptance criterion is 
within 4%, suggesting that the probability of falsely identifying an arm that is not 
actually safer than the control is very well controlled. In general, when there are 
40 participants per arm, the simulation has shown good operating characteristics. For the 
primary analysis, the arm that meets the interim threshold based on efficacy and has the 
highest posterior probability of meeting the acceptance criterion for safety will be 
identified. The lower 95% CI of the difference in incidence rates between the identified 
arm and control Arm A will need to be >2.5% in order for the identified arm to be 
declared to show an improved toxicity profile compared with that of the control arm. 
Table 14 
Study Safety Operating Characteristics 
Incidence rate of 
Grade 2 corneal event 
(KVA scale) 
Probability of identifying an arm that meets acceptance criterion: 
P (incidence rate of control – incidence rate of test arm >0.17) >0.7 
Control Arm 
Test Arm 
0.5 
0.1 
>0.99 
0.5 
0.2 
0.95 
0.5 
0.3 
0.67 
0.5 
0.35 
0.42 
0.5 
0.4 
0.23 
0.5 
0.45 
0.1 
0.5 
0.5 
0.04 
0.632 
0.1 
>0.99 
0.632 
0.2 
>0.99 
0.632 
0.3 
0.97 
0.632 
0.35 
0.92 
0.632 
0.4 
0.8 
0.632 
0.45 
0.56 
0.632 
0.5 
0.37 
0.632 
0.55 
0.18 
0.632 
0.6 
0.08 
0.632 
0.632 
0.03 
0.7 
0.1 
>0.99 
0.7 
0.2 
>0.99 
0.7 
0.3 
0.99 
0.7 
0.35 
0.99 
0.7 
0.4 
0.94 

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Incidence rate of 
Grade 2 corneal event 
(KVA scale) 
Probability of identifying an arm that meets acceptance criterion: 
P (incidence rate of control – incidence rate of test arm >0.17) >0.7 
Control Arm 
Test Arm 
0.7 
0.45 
0.84 
0.7 
0.5 
0.68 
0.7 
0.55 
0.42 
0.7 
0.6 
0.23 
0.7 
0.632 
0.16 
0.7 
0.7 
0.03 
Abbreviations: KVA=keratopathy visual acuity. 
9.2.2. 
Safety Stopping Rule for Arm E 
Unacceptable toxicity is defined as the rate of Grade 4 corneal events (KVA scale) being 
significantly (1-sided alpha of 0.025) higher than 5%. Continuous monitoring will be 
conducted once 5 participants are dosed in Arm E. The observed number of participants 
who experience Grade 4 corneal events (KVA scale) will be compared against the safety 
stopping rule in Table 15. Enrollment may stop for Arm E if the safety stopping rule is 
met based on the totality of the safety data. For example, if 2 out of 5 participants 
experience Grade 4 corneal events (KVA scale), enrollment for the arm may stop after 
review of all safety data. Operating characteristics for the stopping rule are provided in 
Section 10.16. 
If Arm E is stopped due to safety, and participants are still on treatment, they will be 
given the opportunity to switch to Arm A in which they will receive study treatment at 
2.5 mg/kg Q3W dosing regimen with dose modification now based on the KVA scale 
instead of on ocular symptoms and visual acuity assessments. 
Table 15 
Safety Stopping Rule for Arm E 
Number of Participants Dosed 
Stop if Number of Participants 
with Grade 4 Corneal Events 
(KVA Scale) is: 
Observed Rate 
5 
2 
0.4 
6-13 
3 
0.23-0.5 
14-20 
4 
0.2-0.29 
Abbreviations: KVA=keratopathy visual acuity. 

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9.3. 
Data Analysis Considerations  
9.3.1. 
Analysis Populations 
For purposes of analysis, the following study populations are defined (Table 16): 
Table 16 
Definitions of Study Analysis Populations 
Population 
Description 
All Screened 
The All Screened Population will consist of all participants who sign the ICF to 
participate in the clinical study. Participants in this population will be used for 
screen failure summary. 
ITT 
The ITT Population will consist of all randomized participants, whether or not 
randomized treatment was administered. This population will be based on the 
treatment to which the participant was randomized and will be the primary 
population for the analysis of efficacy data. Any participant who receives a 
treatment randomization number will be considered to have been randomized. 
Safety 
All randomized participants who receive at least 1 dose of study treatment. 
Participants will be analyzed according to the treatment they actually received. 
PK 
The PK Population will consist of those participants in the Safety Population from 
whom at least 1 post-treatment PK sample has been obtained and analyzed. This 
population will be the primary population for PK analyses. 
Evaluable  
population (IA only) 
The Evaluable Population for the interim analysis will consist of all participants 
who have received 2 doses of study treatment and have completed 1 disease 
assessment after the second dose, or confirmed PD or death. This population will 
be the primary population for futility assessment at Interim analysis only. 
Abbreviations: IA=interim analysis; ICF=Informed Consent Form; ITT=Intent-to-Treat; PK=pharmacokinetic. 
9.4. 
Key Elements of Statistical Analysis Plan  
Data will be listed and summarized according to the GSK reporting standards, where 
applicable. Complete details will be documented in the Statistical Analysis Plan (SAP). 
Any deviations from, or additions to, the original analysis plan described in this protocol 
will be documented in the SAP and final clinical study report (CSR). 
As it is anticipated that accrual will be spread thinly across centers and summaries of data 
by center would be unlikely to be informative, data from all participating centers will be 
pooled before analysis. 
All data up to the time of study completion/withdrawal from study/treatment switching 
will be included in the analysis, regardless of duration of treatment. 
As the duration of treatment for a given participant will depend on efficacy and 
tolerability, the duration of follow-up will vary between participants. Consequently, there 
will be no imputation for missing data. 
Demographic and baseline characteristics will be summarized. 
All statistical analyses will be performed by GSK (the sponsor) or under the authority of 
the sponsor. A general description of the statistical methods to be used to analyze the 
clinical activity and safety data is outlined below. Statistical analyses will be performed 

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for each treatment arm separately and the alternative regimens in Arm B to D will be 
compared to Arm A to decide whether a regimen has shown improved safety based on 
the acceptance criterion. 
9.4.1. 
Dosing Based on Baseline Disease Characteristics – Virtual 
Treatment Arm 
Approaches for individualized dosing will be investigated by combining participants 
from different treatment arms based on specific selection criteria to create a virtual 
“treatment arm” for the resulting dosing approach. Each virtual treatment arm can then be 
summarized for corneal toxicity and efficacy and compared to the treatment Arms A to 
D. Examples include the following: 
• 
International Staging System (ISS) stage-based dosing: 
o Arm B (1.9 mg/kg Q3W) for ISS I and II and Arm A (2.5 mg/kg Q3W) for 
ISS III. 
Combine the ISS I/II participants at the 1.9 mg/kg Q3W dose from Arm B and the 
ISS III participants at 2.5 mg/kg Q3W from Arm A to create an ISS stage-based 
dosing treatment arm of 1.9 mg/kg Q3W in ISS I/II and 2.5 mg/kg Q3W in 
ISS III. 
o Arm C (2.5 mg/kg Q6W) for ISS I, Arm B (1.9 mg/kg Q3W) for ISS II, and 
Arm A (2.5 mg/kg Q3W) for ISS III. 
Other similar analyses possibly also involving other disease characteristics at baseline 
may be included in the SAP, and specific details will be provided in the SAP. 
9.4.2. 
General Considerations 
Descriptive statistics for safety, efficacy, and pharmacokinetic data will be generated to 
summarize the information for each dosing regimen. Demographics, baseline 
characteristics, and efficacy will be summarized using the Intent-to-Treat (ITT) 
Population. AEs, clinical laboratory parameters, and vital signs will be summarized using 
the Safety Population. Pharmacokinetic parameter values will be summarized using the 
Pharmacokinetic (PK) Population. Appropriate subgroup analyses may be performed if 
data permit. 
9.4.3. 
Safety Analyses 
All safety analyses will be performed on the Safety Population. All serially collected 
safety endpoints (e.g., laboratory tests, vital signs, ECGs) will be summarized according 
to the scheduled, nominal visit at which they were collected and across all on-treatment 
time points using a “worst-case” analysis. Complete details of the safety analyses will be 
provided in the SAP. 

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Table 17 
Statistical Analysis Methods: Safety 
Endpoint 
Statistical Analysis Methods 
Primary 
Incidence rate of Grade ≥2 corneal events according to the KVA scale is the primary 
endpoint. It is calculated as the percentage of participants with Grade ≥2 corneal events 
assessed by KVA scale.  
Secondary 
• 
Cumulative event rate of corneal events to Week 16 (KVA scale) is defined as the 
percentage of corneal events of each grade out of all the events up to Week 16. 
• 
Incidence rate of corneal events by grade (KVA scale) is defined as the percentage of 
participants with corneal events by grade according to the KVA scale in the respective 
treatment group. 
• 
The exposure-adjusted incidence rate is defined as the number of participants with 
corneal events divided by the total exposure time among participants in the respective 
treatment group at risk of an initial occurrence of the event. 
• 
Median duration of dose delay is defined as the median duration in time of all the dose 
delays in the respective treatment group. 
• 
Percentage of participants requiring dose reduction is defined as the percentage of 
participants that require dose reduction out of all the participants in the respective 
treatment group. 
• 
Percentage of participants requiring dose delay is defined as the percentage of 
participants that require dose delay out of all the participants in the respective 
treatment group. 
• 
Percentage of participants requiring study treatment discontinuation is defined as the 
percentage of participants that require study treatment discontinuation out of all the 
participants in the respective treatment group. 
Cumulative incidence of corneal events by grade (KVA scale) is calculated as the 
number of new events divided by the total number of individuals in the population 
at risk for a specific time interval. Assuming that the times experiencing the event 
of interest are: 𝑡1, 𝑡𝑗−1, and 𝑡𝑗, the overall event (both events of interest and 
competing risk events) free rate up to, but not including time 𝑡𝑗, will be obtained 
from the Kaplan-Meier estimates and is denoted by 𝑆(𝑡𝑗). 
• 
A participant’s toxicity index score is defined as a function of the ordered toxicity 
grades, where the toxicity grades are represented in descending order by the 
sequence. The maximum toxicity grade is the integer part of the final score: 
𝑇𝐼= Σ𝑖=1
𝑛
𝑋𝑖
∏
(1 + 𝑋𝑗)
𝑖−1
𝑗=1
 
• 
Duration of corneal events (KVA scale) for each participant is defined as the sum of all 
the corneal events. 
• 
Percentage of time on study with corneal events (KVA scale) is defined as the 
percentage of time that a participant has corneal events out of the total time that a 
participant is on the study. 
• 
Change in BCVA (ΔlogMAR) is defined as the change of logMAR compared with 
baseline or the first visit after the cataract surgery. 
Exploratory Exploratory analyses will be described in the SAP. 
Abbreviations: AE=adverse event; (Δ)logMAR=(change in) logarithm of the minimum angle of resolution; 
KVA=keratopathy visual acuity; SAP=Statistical Analysis Plan. 

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9.4.3.1. 
Extent of Exposure 
The number of participants administered study treatment will be summarized according 
to the duration of therapy. 
9.4.3.2. 
Adverse Events 
AEs will be coded using the standard MedDRA and grouped by SOC. Severity of corneal 
events will be graded using the KVA scale (Table 8). Severity of all other AEs will be 
graded by the investigator according to the NCI-CTCAE Version 5.0. 
Events will be summarized by frequency and proportion of total participants, SOC, and 
preferred term. Separate summaries will be given for all AEs, treatment-related AEs, 
ocular AEs, SAEs, and AEs leading to discontinuation of study treatment. AEs, if listed 
in the NCI-CTCAE Version 5.0, will be summarized by the maximum grade. Otherwise, 
the AEs will be summarized by maximum intensity. 
Characteristics (e.g., number of occurrences, action taken, grade, etc.) of the following 
AEs of special interest will be summarized separately: corneal events, thrombocytopenia, 
and IRRs. 
The incidence of deaths and the primary cause of death will be summarized. 
9.4.3.3. 
Clinical Laboratory Evaluations 
The evaluation of clinical laboratory tests will focus on selected laboratory analytes from 
the hematology and blood chemistry panel. 
Hematology and clinical chemistry data will be summarized using frequencies and 
proportions according to NCI-CTCAE Version 5.0. Laboratory test results outside the 
reference ranges that do not have an associated NCI-CTCAE criterion will be 
summarized using proportions. Further details will be provided in the SAP. 
Descriptive statistics (mean, standard deviation, median, range) will be used to 
summarize observed laboratory values and change from baseline in observed value at 
each scheduled visit or worst-case postbaseline, as appropriate. 
9.4.3.4. 
Immunogenicity 
For each participant, the results and titers of anti-belantamab mafodotin binding 
antibodies will be listed for each assessment time point. The frequency and percentage of 
participants with positive and negative results will be summarized for each assessment 
time and overall for each participant by treatment arm and for all treatment arms 
combined. Detailed information will be included in the SAP. 
9.4.3.5. 
Other Safety Measures 
Data for vital signs and ECGs will be summarized based on pre-determined criteria 
identified to be of potential clinical concern. For continuous variables, these summaries 
will include sample size, mean, median, standard deviation, minimum, and maximum. 

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For categorical variables, the summaries will include frequencies and corresponding 
percentages. Further details will be provided in the SAP. 
9.4.4. 
Efficacy Analyses 
Analysis of efficacy endpoints will be based on investigator-assessed confirmed response 
and dates according to IMWG criteria [Kumar, 2016] with the ITT Population unless 
otherwise specified. The analytical methods planned for each endpoint are described in 
Table 18. 
The number and percentage of participants with the best confirmed response in the 
following response categories will be summarized by treatment arm: sCR, CR, VGPR, 
PR, overall response (sCR+CR+VGPR+PR), minimal response (MR), stable disease 
(SD), PD, and not evaluable. The corresponding exact 95% CI for ORR will also be 
provided. Participants with unknown or missing responses will be treated as 
non-responders, i.e., these participants will be included in the denominator when 
calculating percentages of response. 

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Table 18 
Statistical Analytical Methods: Efficacy 
Endpoint 
Description 
Secondary 
• 
ORR defined as percentage of participants with a confirmed PR or better (i.e., PR, 
VGPR, CR and sCR), according to the 2016 IMWG response criteria [Kumar, 2016]. 
• 
DoR is defined as the time from first documented evidence of PR or better until the 
earliest date of PD or death due to any cause among participants who achieve a 
response (i.e., confirmed PR or better) as assessed by the investigator per IMWG 
criteria [Kumar, 2016]. Responders without PD will be censored at the censoring time 
point for TTP.  
• 
Distribution of DoR will be summarized using the Kaplan-Meier method by treatment 
arm. The median, 25th, and 75th percentiles of DoR will be estimated and 
corresponding 95% Cis will be estimated using the Brookmeyer-Crowley method 
[Brookmeyer, 1982].  
• 
TTR is defined as the time between the date of randomization and the first 
documented evidence of response (PR or better), among participants who achieve a 
response (i.e., confirmed PR or better) as assessed by the investigator per IMWG 
criteria [Kumar, 2016]. 
• 
TTR will be summarized descriptively by treatment arm using medians and quartiles in 
the subset of participants with a confirmed response of PR or better as the best overall 
response. Sensitivity analysis will be conducted using investigator-assessed 
responses. 
• 
TTP is defined as the time from randomization until the earliest date of PD as 
assessed by the investigator per IMWG criteria [Kumar, 2016]], or death due to PD. 
Determination of dates of TTP event and dates for censoring will be described in the 
SAP. 
• 
TTP analysis will be conducted using a similar approach as for the PFS analysis. 
• 
PFS, defined as the time from randomization until the earliest date of documented PD 
as assessed by the investigator per IMWG criteria [Kumar, 2016] or death due to any 
cause. PFS will be summarized by arm, and median, first, and third quartiles of PFS 
will be estimated using the Kaplan-Meier method. 
• 
OS, defined as the interval of time from randomization to the date of death due to any 
cause. Participants who are alive will be censored at the date of last contact. OS will 
be summarized by arm, and median, first, and third quartiles of OS will be estimated 
using the Kaplan-Meier method.  
Exploratory Exploratory analyses will be described in the SAP. 
Abbreviations: CR=confirmed response; IMWG=International Myeloma Working Group; ORR=overall response rate; 
OS=overall survival; PD=progressive disease; PFS=progression-free survival; PR=partial response; 
SAP=Statistical Analysis Plan; sCR=stringent complete response; TTP=time to progression; TTR=time to 
response; VGPR=very good partial response. 
9.4.5. 
Pharmacokinetic Analyses 
9.4.5.1. 
Pharmacokinetic Data Analyses 
Pharmacokinetic analyses will be the responsibility of Clinical Pharmacology Modelling 
and Simulation, GSK. Population pharmacokinetic methods will be used for 
pharmacokinetic analyses. 
Plasma belantamab mafodotin concentration-time data may be combined with data from 
other studies and analyzed using a population pharmacokinetic approach. The initial 

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analysis will use the then-current population pharmacokinetic model to generate post-hoc 
belantamab mafodotin pharmacokinetic parameter estimates. Based on the individual 
post-hoc parameter values, dosing information, and sample collection times, belantamab 
mafodotin plasma concentrations at the time of sample collection will be predicted for 
each participant. Model evaluation will consist of comparison of model-predicted and 
observed concentrations. If necessary, model estimation will be performed. Results of 
this analysis may be provided in a separate report. 
CPMS analysts may be provided with population PK and PK/PD datasets for population 
PK and PK/PD model refinement before database lock. 
9.4.5.2. 
Statistical Analysis of Pharmacokinetic Data 
Statistical analyses of the pharmacokinetic data will be the responsibility of Clinical 
Pharmacology Modeling and Simulation (CPMS), GSK. 
Linear and semi-logarithmic individual concentration-time profiles and mean and median 
profiles (when appropriate) will be plotted for belantamab mafodotin and cys-mcMMAF. 
Concentrations of belantamab mafodotin and cys-mcMMAF will be listed for each 
participant and summarized (when appropriate) by planned time point and treatment arm. 
Pharmacokinetic parameters will be listed and summarized descriptively (mean, standard 
deviation, median, minimum, maximum, geometric mean, and the standard deviation, 
CV%, and 95% CI of log-transformed parameters) by cycle and treatment arm for each 
analyte. 
9.4.6. 
Pharmacokinetic/Pharmacodynamic Analyses 
If deemed appropriate and if data permit, exposure-response relationships between 
belantamab mafodotin exposure and clinical activity and/or toxicity may be explored 
using population methods. If data permit, the effects of covariates may be explored. Data 
may be combined with data from other studies and results of this analysis may be 
provided in a separate report. 
9.4.7. 
Biomarker/Translational Research Analyses 
BCMA expression in BM samples and sBCMA levels in circulation obtained pre-dose 
will be quantified and reviewed/analyzed for a potential relationship to response. 
Post-dose measurements of sBCMA will be evaluated for dynamic changes during and 
after treatment. If data permit, additional exploratory analyses may be performed for 
novel biomarkers. Data for these exploratory analyses that are received after database 
freeze will not constitute a database unfreeze and, if warranted, the results of these 
analyses will be provided in a separate report. 
Full details of analysis approaches will be provided in the SAP. 

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9.4.8. 
Patient-Reported Outcomes Analyses 
Group-level descriptive statistics and evaluation of within-participant meaningful change 
will be used to summarize scores derived from different questionnaires and change from 
baseline at each scheduled visit. Additional details of these analyses will be provided in 
the SAP. 
9.5. 
Interim Analysis 
An interim analysis is planned when approximately 15 participants each in Arms A to D 
have received 2 doses of study treatment with 1 disease assessment following the second 
dose or confirmed PD per IMWG [Kumar, 2016] or death.  
Table 19 displays the probability of stopping an arm early at interim analysis according to 
different true response rates of the experimental regimens (Arms B to D). The interim 
analysis threshold of 2 responders provides reasonable protection of study participants 
from an ineffective treatment. 
Table 19 
Arm Stopping Probability at Interim Analysis by True Response Rate 
True Response Rate 
Probability of Arm Stopping at ≤2 Responders 
0.31 
0.11 
0.25 
0.24 
0.2 
0.4 
0.15 
0.6 
If Arm D is stopped due to futility, Arm E will also be stopped. If Arms B, C, D, or E are 
stopped due to futility, and participants are still on treatment, they will be given the 
opportunity to switch to 2.5 mg/kg Q3W (Arm A/control regimen) with dose 
modifications based on the KVA scale. 
Available data from Arm E will be provided at the time of the interim analysis.  
Additional interim analyses may also be conducted as deemed necessary for decision 
making by the Independent Data Monitoring Committee (IDMC). 
The SAP will describe the planned interim analyses in greater detail. 
9.5.1. 
Independent Data Monitoring Committee 
An IDMC consisting of at least 2 physicians and 1 statistician will review safety and 
efficacy data as defined in the IDMC Charter. Additional details, including the list of 
outputs supporting decision making at the interim analysis, will be provided in the IDMC 
Charter. 
The first IDMC review meeting is planned when approximately 15 participant each in 
Arms A to D have received 2 doses of study treatment with 1 disease assessment after the 
second dose, or confirmed PD per IMWG [Kumar, 2016] or death. Other IDMC review 

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meetings will be planned on an ad-hoc basis based on any safety signals. Additional 
details will be provided in the IDMC Charter. 
10. 
SUPPORTING DOCUMENTATION AND OPERATIONAL 
CONSIDERATIONS 
10.1. 
Appendix 1: Eye Care Specialist’s Qualifications and 
Requirements 
For examiners with a degree in ophthalmology or optometry, those involved in eye 
evaluations in the protocol must be able to provide comprehensive eye care to 
participants, ranging from routine check-ups to treatment and ongoing management of 
visual disease. This includes, at a minimum, the ability to perform the following 
activities: 
• 
Comprehensive eye examination 
• 
Visual acuity with manual refraction examination and analysis of results 
• 
Anterior segment (slit lamp) examination and analysis of results 
• 
Intraocular pressure measurement 
• 
Dilated fundoscopic examination 
• 
Diagnosis and treatment of ocular issues and diseases such as keratopathy or 
glaucoma 

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10.2. 
Appendix 2: International Staging System for Multiple 
Myeloma 
The International Staging System (ISS) for multiple myeloma will be used to stratify 
participants into this study; the staging guidelines are as follows: 
Stage 
Criteria 
I 
Serum β2-microglobulin <3.5 mg/L, serum albumin ≥3.5 g/dL 
II 
Not Stage I or III 
III 
Serum β2-microglobulin ≥5.5 mg/L 
Source: Greipp, 2005. 

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10.3. 
Appendix 3: Guidelines for the Determination of the Number 
of Prior Lines of Therapy in Multiple Myeloma 
The number of prior lines of anti-multiple myeloma therapy will be used to stratify 
participants into this study and should be determined according to the guidelines by 
Rajkumar et al [Rajkumar, 2015] as follows: 
Definition of Line of Therapy 
• 
A line of therapy consists of the following: 
• 
≥1 complete cycle of a single agent or 
• 
A regimen consisting of a combination of several drugs or 
• 
A planned sequential therapy of various regimens (e.g., 3 to 6 cycles of initial 
therapy with bortezomib-dexamethasone [VD] followed by stem cell transplantation 
[SCT], consolidation, and lenalidomide maintenance is considered 1 line). 
New Line of Therapy 
A treatment is considered a new line of therapy if any 1 of the following 3 conditions are 
met: 
1. If a line of therapy is discontinued for any reason and a different therapy is 
started, it should be considered a new line of therapy. 
Note: A regimen/line is considered to have been discontinued if all the drugs in that 
given regimen have been stopped. A line is not considered to have been discontinued 
if some of the drugs of the regimen, but not all, have been discontinued. 
• 
For example, toxicity with lenalidomide plus low-dose dexamethasone (RD) as 
pre-transplant induction, and therefore treatment is switched to bortezomib, 
cyclophosphamide, and dexamethasone (VCD). In that case, RD is counted as line 1 
and VCD (and subsequent planned SCT) as line 2. 
2. Unplanned addition or substitution of 1 or more drugs (or combination of 
drugs) in an existing regimen due to any reason is considered a new line of 
therapy. 
• 
For example, RD as initial therapy, and, due to inadequate response, bortezomib is 
added (RVD); counted as 2 lines. In that case, enter RD as line 1 and RVD as line 2. 
3. In patients undergoing >1 SCT (except in the case of a planned tandem SCT 
with a predefined interval [such as 3 months]), each SCT (autologous or 
allogeneic) should be considered a new line of therapy regardless of whether the 
conditioning regimen used is the same or different. 
• 
For example, post-transplant observation without maintenance, and then, due to 
paraprotein rise 6 months later, lenalidomide is started, which is not planned 
maintenance; hence, lenalidomide will be considered as a new line. 

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Interruptions and Dose Modifications: 
1. If a regimen is interrupted or discontinued for any reason and the same drug or 
combination is restarted without any other intervening regimen, then it should be 
counted as a single line. 
• 
For example, RD as initial therapy for 2 years, then stopped due to plateau phase (or 
any other cause), and then restarted 6 months later due to progression: this should be 
counted as 1 line. 
2. If a regimen is interrupted or discontinued for any reason, and then restarted at a later 
time point but 1 or more other regimens were administered in between, or the 
regimen is modified through the addition of 1 or more agents, then it should be 
counted as 2 lines 
• 
For example: RVD followed by progression at some point, and then VCD is used; 
then, RVD is used again as a salvage strategy: this is counted as 3 lines. Enter RVD 
as line 1, VCD as line 2, and then RVD as line 3. 
3. Modification of the dosing of the same regimen should not be considered a new line 
of therapy. 

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10.4. 
Appendix 4: Decentralized and Remote Assessment 
Approaches 
Decentralized Ophthalmologic Examinations 
Where applicable country and local regulations and infrastructure allow, 
protocol-required eye examinations may be done at a specified alternative eye care 
specialist clinic. Activities that may be done as part of decentralized eye examinations 
must follow the schedule provided in the SoA (Section 1.3) and include the following: 
• 
Visual acuity by near-chart visual acuity or pinhole 
• 
Slit lamp examination 
• 
Tonometry (intraocular pressure measurement) 
• 
Ophthalmoscopy 
The participant should be informed of any potential risks associated with decentralized 
ophthalmologic examinations and sign a revised ICF, if required. IRBs/IECs should be 
informed and/or approve of this change in approach and the process documented in study 
files. 
Remote Patient-Reported Outcomes Administration 
Where applicable country and local regulations and infrastructure allow, remote 
patient-reported outcome (PRO) administration may be permitted. Remote PRO 
administration is defined as administration of protocol PROs by a qualified third party 
over the telephone. The remote PRO administrator will use the versions of the PROs 
designed for verbal administration. The remote PRO administrator will have access to the 
electronic PRO portal for the study and input participant responses as the interview is 
being conducted. 
The participant should be informed of any potential risks associated with the remote PRO 
administration and sign a revised ICF if required. IRBs/IECs should be informed and/or 
approve of this change in approach and the process documented in study files. 

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10.5. 
Appendix 5: Modified Diet in Renal Disease Formula 
The Modified Diet in Renal Disease (MDRD) formula for calculating the estimated 
glomerular filtration rate (eGFR) is as follows: 
eGFR = 175 × (serum creatinine)-1.154 × (Age)-0.203 × (0.742 if female) × (1.212 if 
African American) 
eGFR is expressed in mL/min/1.73 m2, serum creatinine is expressed in mg/dL, and age 
is expressed in years. 
The following website will auto-calculate the creatinine clearance: 
http://nephron.org/cgi-bin/MDRD_GFR/cgi 

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10.6. 
Appendix 6: Liver Safety Required Actions and Follow-Up 
Assessments 
Liver chemistry stopping and increased monitoring criteria have been designed to 
assure participant safety and evaluate liver event etiology. 
Liver chemistry stopping criteria and required follow-up assessments are as follows: 
Liver Chemistry Stopping Criteria – Liver Stopping Event 
ALT-absolute 
ALT 5xULN 
ALT Increase 
ALT 3xULN persists for 4 weeks 
Bilirubin1, 2 
ALT 3xULN and total bilirubin 2xULN (>35% 
direct bilirubin)  
INR2  
ALT 3xULN and INR>1.5 
Cannot Monitor 
ALT 3xULN and cannot be monitored weekly for 
4 weeks 
Symptomatic3 
ALT 3xULN associated with symptoms (new or 
worsening) believed to be related to liver injury or 
hypersensitivity 
Required Actions, Monitoring, and Follow-Up Assessments 
Actions 
Follow-Up Assessments 
• 
Immediately discontinue study treatment 
• 
Report the event to GSK within 24 hours 
• 
Complete the liver event form and complete 
SAE data collection tool if the event also meets 
the criteria for an SAE2 
• 
Perform liver event follow-up assessments as 
described in the Follow-Up Assessments 
column 
• 
Monitor the participant until liver chemistries 
resolve, stabilize, or return to within baseline 
(see MONITORING) 
MONITORING: 
If ALT3xULN and total bilirubin 2xULN or 
INR>1.5: 
• 
Repeat liver chemistries (include ALT, AST, 
ALP, total bilirubin, and INR) and perform liver 
event follow-up assessments within 24 hours 
• 
Monitor participants twice weekly until liver 
chemistries resolve, stabilize, or return to within 
baseline 
• 
A specialist or hepatology consultation is 
recommended 
For all other criteria (bilirubin <2xULN and 
INR1.5): 
• 
Repeat liver chemistries (include ALT, AST, 
ALP, total bilirubin, and INR) and perform liver 
• 
Viral hepatitis serology4 
• 
Obtain INR and recheck with each liver 
chemistry assessment until the 
aminotransferases values show downward 
trend 
• 
Blood sample for PK analysis and a blood 
sample for sBCMA, obtained within 70 days 
after last dose of belantamab mafodotin5 
• 
Serum CPK, LDH, GGT, GLDH, and serum 
albumin 
• 
Fractionate bilirubin, if total bilirubin 2xULN 
• 
Obtain complete blood count with differential 
to assess eosinophilia 
• 
Record the appearance or worsening of 
clinical symptoms of liver injury, or 
hypersensitivity, on the liver event form 
• 
Record use of concomitant medications on 
the concomitant medications report form 
including acetaminophen, herbal remedies, 
recreational drugs, or other over-the-counter 
medications 
• 
Record alcohol use on the liver event alcohol 
intake report form 
If ALT3xULN and total bilirubin 2xULN or 
INR>1.5 obtain the following in addition to the 
assessments listed above: 
• 
Anti-nuclear antibody, anti-smooth muscle 
antibody, Type 1 anti-liver kidney microsomal 

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event follow-up assessments within 24 to 
72 hours 
• 
Monitor participants weekly until liver 
chemistries resolve, stabilize, or return to within 
baseline 
RESTART/RECHALLENGE: 
• 
Restart/rechallenge is allowed per protocol, 
but do not resume study treatment unless 
GSK approval is granted. If 
restart/rechallenge is not granted, 
permanently discontinue study treatment and 
continue participant in the study for any 
protocol-specified follow-up assessments. 
Refer to restart/rechallenge guidelines in 
Section 10.12. 
antibodies, and quantitative total 
immunoglobulin G (IgG or gamma globulins) 
• 
Serum acetaminophen adduct assay should 
be conducted (where available) to assess 
potential acetaminophen contribution to liver 
injury unless acetaminophen use is very 
unlikely in the preceding week (e.g., where 
the participant has been resident in the 
clinical unit throughout) 
• 
Liver imaging (ultrasound, MRI, or CT) to 
evaluate liver disease; (complete liver imaging 
form) 
• 
Liver biopsy may be considered and 
discussed with local specialist if available, for 
instance: 
o In participants when serology raises the 
possibility of autoimmune hepatitis 
o In participants when suspected 
drug-induced liver injury progressor or 
fails to resolve on withdrawal of study 
treatment 
o In participants with acute or chronic 
atypical presentation 
• 
If liver biopsy conducted, complete liver 
biopsy form 
Abbreviations: ALT=alanine aminotransferase; AST=aspartate aminotransferase; CPK=serum creatine phosphokinase; 
CT=computed tomography; DNA=deoxyribonucleic acid; eCRF=electronic Case Report Form; GGT=gamma 
glutamyl transferase; GLDH=glutamate dehydrogenase; GSK=GlaxoSmithKline; Ig=immunoglobulin; 
INR=international normalized ratio; LDH=lactate dehydrogenase; MRI=magnetic resonance imaging; 
PK=pharmacokinetic(s); RNA=ribonucleic acid; SAE=serious adverse event; sBCMA=soluble B-cell maturation 
antigen; SRM=Study Reference Manual; ULN=upper limit of normal. 
1. 
Serum bilirubin fractionation should be performed if testing is available. If serum bilirubin fractionation is not 
immediately available, discontinue study treatment for that participant if ALT 3xULN and bilirubin 2xULN. 
Additionally, if serum bilirubin fractionation testing is unavailable, record presence of detectable urinary 
bilirubin on dipstick, indicating direct bilirubin elevations and suggesting liver injury. 
2. 
All events of ALT 3xULN and total bilirubin 2xULN (>35% direct bilirubin) or ALT 3xULN and INR>1.5, which 
may indicate severe liver injury (possible “Hy’s law”), must be reported as an SAE (excluding studies of 
hepatic impairment or cirrhosis); the INR threshold value stated will not apply to participants receiving 
anticoagulants 
3. 
New or worsening symptoms believed to be related to liver injury (such as fatigue, nausea, vomiting, right upper 
quadrant pain or tenderness, or jaundice) or believed to be related to hypersensitivity (such as fever, rash, or 
eosinophilia) 
4. 
Includes: Hepatitis A IgM antibody; hepatitis B surface antigen, and hepatitis B core antibody (IgM); hepatitis C 
RNA; cytomegalovirus IgM antibody; Epstein-Barr viral capsid antigen IgM antibody (or if unavailable, obtain 
heterophile antibody or monospot testing); hepatitis E IgM antibody. In those with underlying chronic hepatitis B at 
study entry (identified by positive hepatitis B surface antigen) quantitative hepatitis B DNA and hepatitis delta 
antibody. If hepatitis delta antibody assay cannot be performed, it can be replaced with polymerase chain reaction 
of hepatitis D RNA virus (where needed) [Le Gal, 2005]. 
5. 
Record the date/time of the PK blood sample draw and the date/time of the last dose of study treatment before the 
blood sample draw on the eCRF. If the date or time of the last dose is unclear, provide the participant’s best 
approximation. If the date/time of the last dose cannot be approximated or a PK sample cannot be collected in the 
time period indicated above, do not obtain a PK sample. Instructions for sample handling and shipping are in the 
laboratory manual. 

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Oncology liver chemistry increased monitoring criteria with continued therapy are 
as follows: 
Liver Chemistry Increased Monitoring Criteria and Actions with Continued Study Treatment – 
Liver Monitoring Event 
Criteria 
Actions 
• 
ALT 3xULN but <5xULN and total bilirubin 
<2xULN or INR 1.5, without symptoms believed 
to be related to liver injury or hypersensitivity and 
who can be monitored weekly for 4 weeks 
• 
Notify the GSK Medical Director within 
24 hours of learning of the abnormality to 
discuss participant safety 
• 
Participant can continue study treatment 
• 
Participant must return weekly for repeat 
liver chemistries (ALT, AST, ALP, total 
bilirubin, and INR) until they resolve, 
stabilize, or return to within baseline 
• 
If, at any time, participant meets the liver 
chemistry stopping criteria, proceed as 
described above 
• 
If, after 4 weeks of monitoring, ALT 
<3xULN, total bilirubin <2xULN, and INR 
1.5, monitor participants twice monthly 
until liver chemistries resolve or return to 
within baseline 
Abbreviations: ALP=alkaline phosphatase; ALT=alanine aminotransferase; AST=aspartate aminotransferase; 
GSK=GlaxoSmithKline; INR=international normalized ratio; ULN=upper limit of normal. 

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10.7. 
Appendix 7: Country-Specific Requirements 
France 
• Additional inclusion criterion for participants in France: A participant is eligible to be 
included in the study only if they are either affiliated to or a beneficiary of a social 
security category. 
• Additional inclusion criterion for participants in France: Only participants who have 
failed at least 4 prior lines of anti-myeloma therapies will be included in the study. 
South Korea 
• Modified inclusion criterion 1 for participants in South Korea: In South Korea, a 
participant must be over 19 years of age inclusive at the time of signing the informed 
consent. 
Taiwan 
• Modified inclusion criterion 1 for participants in Taiwan: In Taiwan, a participant 
must be at least 20 years of age at the time of signing the informed consent. 
Thailand 
• Modified inclusion criterion 1 for participants in Thailand: In Thailand, a participant 
must be at least 20 years of age at the time of signing the informed consent. 
 

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10.8. 
Appendix 8: Eastern Cooperative Oncology Group (ECOG) 
Performance Status 
Performance 
Grade 
Description 
0 
Normal activity. Fully active, able to carry on all pre-disease performance without 
restriction. 
1 
Symptoms, but ambulatory. Restricted in physically strenuous activity, but ambulatory 
and able to carry out work of a light or sedentary nature (e.g., light housework, office 
work) 
2 
In bed <50% of the time. Ambulatory and capable of all self-care, but unable to carry 
out any work activities. Up and about more than 50% of waking hours. 
3 
In bed >50% of the time. Capable of only limited self-care, confined to bed or chair 
more than 50% of waking hours. 
4 
100% bedridden. Completely disabled. Cannot carry on any self-care. Totally confined 
to bed or chair. 
5 
Dead. 
Source: Oken, 1982. 

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10.9. 
Appendix 9: Contraceptive and Barrier Guidance 
Contraceptive and barrier guidance for participants is provided in this appendix. 
10.9.1. 
Definitions 
Woman of Childbearing Potential (WOCBP) 
Women in the following categories are considered WOCBP (fertile): 
1. After menarche 
2. From the time of menarche until becoming post-menopausal unless permanently 
sterile (see below) 
Note: 
• A post-menopausal state is defined as no menses for 12 months without an alternative 
medical cause. 
o A high follicle-stimulating hormone (FSH) level in the post-menopausal range 
may be used to confirm a post-menopausal state in women not using hormonal 
contraception or hormone replacement therapy (HRT). However, in the absence 
of 12 months of amenorrhea, confirmation with >1 FSH measurement is required. 
o Females on HRT and whose menopausal status is in doubt will be required to use 
one of the non-estrogen hormonal, highly effective contraception methods if they 
wish to continue their HRT during the study. Otherwise, they must discontinue 
HRT to allow confirmation of post-menopausal status before study enrollment. 
• Permanent sterilization methods (for the purpose of this study) include: 
o Documented hysterectomy 
o Documented bilateral salpingectomy 
o Documented bilateral oophorectomy 
For individuals with permanent infertility due to an alternate medical cause other 
than the above, (e.g., Mullerian agenesis, androgen insensitivity, gonadal 
dysgenesis), investigator discretion should be applied to determining study entry. 
Note: Documentation can come from the site personnel’s review of the 
participant’s medical records, medical examination, or medical history interview. 
If fertility is unclear (e.g., amenorrhea in adolescents or athletes) and a menstrual 
cycle cannot be confirmed before first dose of study treatment, additional 
evaluation should be considered. 

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Woman of Nonchildbearing Potential (WONCBP) 
Women in the following categories are considered WONCBP: 
1. Pre-menopausal female with permanent infertility due to one of the following 
procedures (for the purpose of this study): 
a. 
Documented hysterectomy 
b. Documented bilateral salpingectomy 
c. 
Documented bilateral oophorectomy 
For individuals with permanent infertility due to an alternate medical cause other 
than the above, (e.g., Mullerian agenesis, androgen insensitivity, gonadal 
dysgenesis), investigator discretion should be applied to determining study entry. 
Note: Documentation can come from the site personnel’s review of the 
participant’s medical records, medical examination, or medical history interview. 
2. Postmenopausal female 
A postmenopausal state is defined as no menses for 12 months without an alternative 
medical cause. 
• A high FSH level in the post-menopausal range may be used to confirm a 
post-menopausal state in women not using hormonal contraception or HRT. 
However, in the absence of 12 months of amenorrhea, confirmation with more 
than one FSH measurement is required. 
• Females on HRT and whose menopausal status is in doubt must discontinue HRT 
to allow confirmation of post-menopausal status before study enrollment. 

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10.9.2. 
Contraception Guidance 
CONTRACEPTIVESa ALLOWED DURING THE STUDY INCLUDE: 
Highly Effective Methodsb That Have Low User Dependency  
Implantable progestogen-only hormone contraception associated with inhibition of ovulationc 
IUD 
IUSc 
Bilateral tubal occlusion 
Azoospermic partner (vasectomized or due to a medical cause) 
• 
Azoospermia is a highly effective contraceptive method provided that the partner is the sole sexual 
partner of the woman of childbearing potential and the absence of sperm has been confirmed. If not, 
an additional highly effective method of contraception should be used. Spermatogenesis cycle is 
approximately 90 days. 
Note: Documentation of azoospermia for a male participant can come from the site personnel’s 
review of the participant’s medical records, medical examination, or medical history interview. 
Highly Effective Methodsb That Are User-Dependent 
Combined (estrogen- and progestogen-containing) hormonal contraception associated with inhibition of 
ovulationc 
• 
Oral 
• 
Intravaginal 
• 
Transdermal 
• 
Injectable 
Progestogen-only hormone contraception associated with inhibition of ovulationc 
• 
Oral 
• 
Injectable 
Sexual abstinence 
• 
Sexual abstinence is considered a highly effective method only if defined as refraining from 
heterosexual intercourse during the entire period of risk associated with the study treatment. The 
reliability of sexual abstinence needs to be evaluated in relation to the duration of the study and the 
preferred and usual lifestyle of the participant. 
Abbreviations: CTFG=Clinical Trial Facilitation Group; IUD=intrauterine device; IUS= Intrauterine hormone-releasing 
system; LAM=lactational amenorrhea method. 
Note: Periodic abstinence (calendar, symptom-thermal, post-ovulation methods), withdrawal (coitus interruptus), 
spermicides only, and LAM are not acceptable methods of contraception for this study. Male condom and female 
condom should not be used together (due to risk of failure from friction). 
a. 
Contraceptive use by men or women should be consistent with local regulations regarding the use of 
contraceptive methods for those participating in clinical studies. 
b. 
Failure rate of <1% per year when used consistently and correctly. Typical use failure rates differ from those when 
used consistently and correctly. 
c. 
Male condoms must be used in addition to hormonal contraception. If locally required, in accordance with CTFG 
guidelines, acceptable contraceptive methods are limited to those which inhibit ovulation as the primary mode of 
action. 

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10.10. 
Appendix 10: Regulatory, Ethical, and Study Oversight 
Considerations 
10.10.1. 
Regulatory and Ethical Considerations 
• This study will be conducted in accordance with the protocol and with the following 
considerations: 
o Consensus ethical principles derived from international guidelines including the 
Declaration of Helsinki and Council for International Organizations of Medical 
Sciences (CIOMS) international ethical guidelines 
o Applicable International Council for Harmonisation of Technical Requirements 
for Pharmaceuticals for Human Use (ICH) Good Clinical Practice (GCP) 
guidelines 
o Applicable laws and regulations. 
• The protocol, protocol amendments, Informed Consent Form (ICF), Investigator’s 
Brochure, and other relevant documents (e.g., advertisements) must be submitted to 
an Institutional Review Board (IRB)/Independent Ethics Committee (IEC) by the 
investigator and reviewed and approved by the IRB/IEC before the study is initiated. 
• Any amendments to the protocol will require IRB/IEC and regulatory authority 
approval before implementation of changes made to the study design, as per national 
requirements, except for changes necessary to eliminate an immediate hazard to study 
participants. 
• Protocols and any substantial amendments to the protocol will require health 
authority approval before initiation, except for changes necessary to eliminate an 
immediate hazard to study participants. 
• The investigator will be responsible for the following actions: 
o Providing written summaries of the status of the study to the IRB/IEC annually or 
more frequently in accordance with the requirements, policies, and procedures 
established by the IRB/EC 
o Notifying the IRB/IEC of serious adverse events or other significant safety 
findings as required by IRB/IEC procedures 
o Providing oversight of the conduct of the study at the site and adherence to 
requirements of 21 Code of Federal Regulations (CFR), ICH guidelines, the 
IRB/IEC, European regulation 536/2014 for clinical studies (if applicable), and all 
other applicable local regulations. 
10.10.2. 
Financial Disclosure 
Investigators and sub-investigators will provide the sponsor with sufficient, accurate 
financial information as requested to allow the sponsor to submit complete and accurate 
financial certification or disclosure statements to the appropriate regulatory authorities. 
Investigators are responsible for providing information on financial interests during the 
course of the study and for 1 year after completion of the study. 

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10.10.3. 
Informed Consent Process 
• The investigator or his/her representative will explain the nature of the study, 
including the risks and benefits, to the participant or their legally authorized 
representative and answer all questions regarding the study. 
• Participants must be informed that their participation is voluntary. Participants or 
their legally authorized representative will be required to sign a statement of informed 
consent that meets the requirements of 21 CFR 50, local regulations, ICH guidelines, 
privacy and data protection requirements, where applicable, and the IRB/IEC or study 
center. 
• Sample testing will be done in accordance with the recorded consent of the individual 
participant. 
• The medical record must include a statement that written informed consent was 
obtained before the participant was enrolled in the study and the date the written 
consent was obtained. The authorized person obtaining the informed consent must 
also sign the ICF. 
• Participants must be re-consented to the most current version of the ICF(s) during 
their participation in the study. 
• A copy of the ICF(s) must be provided to the participant or their legally authorized 
representative. 
GSK (alone or working with others) may use participant’s coded study data and samples 
and other information to carry out this study; understand the results of this study; learn 
more about belantamab mafodotin or about the study disease; publish the results of these 
research efforts; work with government agencies or insurers to have belantamab 
mafodotin approved for medical use or approved for payment coverage. 
The ICF contains a separate section that addresses the use of participant data and 
remaining samples for optional further research. The investigator or authorized designee 
will inform each participant of the possibility of further research not related to the 
study/disease. Participants will be told that they are free to refuse to participate and may 
withdraw their consent at any time and for any reason during the storage period. A 
separate signature will be required to document a participant’s agreement to allow any 
participant data and/or remaining leftover samples to be used for further research not 
related to the study/disease. Participants who decline further research will tick the 
corresponding “No” box. 
In case of unexpected pregnancy, participant must be informed that PI such as date of 
birth and sex of the baby will be collected as part of safety follow-up. Consent for 
collection of information about the baby may be obtained from the participant and/or 
their partner per local regulations. 
If partners of male participants become pregnant during the study, consent will need to be 
obtained or notification given per local regulation to the partner before collecting their PI 
such as, last menstrual period and year of birth, or the PI such as date of birth and sex of 
their baby as part of safety follow-up. 

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10.10.4. 
Data Protection 
• Participants will be assigned a unique identifier by the sponsor. Any participant 
records or datasets that are transferred to the sponsor will contain the identifier only; 
participant names or any information which would make the participant identifiable 
will not be transferred. 
• The participant must be informed that his/her personal study-related data will be used 
by the sponsor in accordance with local data protection law. The level of disclosure 
must also be explained to the participant who will be required to give consent for 
their data to be used as described in the informed consent. 
• The participant must be informed that his/her medical records may be examined by 
Clinical Quality Assurance auditors or other authorized personnel appointed by the 
sponsor, by appropriate IRB/IEC members, and by inspectors from regulatory 
authorities. 
10.10.5. 
Committees Structure 
An Independent Data Monitoring Committee (IDMC) consisting of at least 2 physicians 
and 1 statistician will review safety and efficacy data as defined in the IDMC Charter. 
Additional details, including the list of outputs supporting decision making at the interim 
analysis, will be provided in the IDMC Charter. 
The first IDMC review meeting is planned when approximately 15 participants each in 
Arms A to D have received 2 doses of study treatment with 1 disease assessment 
following the second dose, or confirmed PD per IMWG [Kumar, 2016] or death. Other 
IDMC review meetings will be planned on an adhoc basis based on any safety signals. 
Additional details will be provided in the IDMC Charter. 
Available data from Arm E will be provided at the time of the IDMC. 
An SRT is in place for each GSK product. It comprises a global cross-functional team 
responsible for the ongoing assessment of benefit-risk for a product. The SRT contribute 
to the continual assessment of incoming new efficacy and safety information. 
10.10.6. 
Dissemination of Clinical Study Data 
• Where required by applicable regulatory requirements, an investigator signatory will 
be identified for the approval of the CSR. The investigator will be provided 
reasonable access to statistical tables, figures, and relevant reports and will have the 
opportunity to review the complete study results at a GSK site or other mutually 
agreeable location. 
• GSK will also provide all investigators who participated in the study with a summary 
of the study results and will tell the investigators what treatment their participants 
received. The investigator(s) is/are encouraged to share the summary results with the 
study participants, as appropriate. 
• Under the framework of the SHARE initiative, GSK intends to make anonymized 
participant-level data from this study available to external researchers for scientific 
analyses or to conduct further research that can help advance medical science or 

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improve participant care. This helps ensure the data provided by study participants 
are used to maximum effect in the creation of knowledge and understanding. 
Requests for access may be made through www.clinicalstudydatarequest.com. 
• The procedures and timing for public disclosure of the protocol and results summary 
and for development of a manuscript for publication for this study will be in 
accordance with GSK Policy. 
10.10.7. 
Data Quality Assurance 
• All participant data relating to the study will be recorded on printed or electronic Case 
Reports Forms (eCRFs) unless transmitted to the sponsor or designee electronically 
(e.g., laboratory data). The investigator is responsible for verifying that data entries 
are accurate and correct by physically or electronically signing the CRF. 
• Guidance on completion of CRFs will be provided in the Case Report Form 
Completion Guidelines. 
• Quality tolerance limits (QTLs) will be pre-defined in the QTL Plan to identify 
systematic issues that can impact participant rights, safety and/or reliability of study 
results. These pre-defined parameters will be monitored during and at the end of the 
study and all deviations from the QTLs and remedial actions taken will be 
summarized in the CSR. 
• The investigator must permit study-related monitoring, audits, IRB/IEC review, and 
regulatory agency inspections and provide direct access to source data documents. 
• Monitoring details describing strategy, including definition of study critical data 
items and processes (e.g., risk-based initiatives in operations and quality such as risk 
management and mitigation strategies and analytical risk-based monitoring), 
methods, responsibilities, and requirements, including handling of noncompliance 
issues and monitoring techniques (central, remote, or on-site monitoring), are 
provided in the Monitoring Plan. 
• The sponsor or designee is responsible for the data management of this study 
including quality checking of the data. Detailed information about study data 
collection and management process including systems used can be found in the study 
Data Management Plan. 
• The sponsor assumes accountability for actions delegated to other individuals (e.g., 
contract research organizations). 
• Records and documents, including signed ICF, pertaining to the conduct of this study 
must be retained by the investigator for 25 years from the issue of the final 
CSR/equivalent summary unless local regulations or institutional policies require a 
longer retention period. No records may be destroyed during the retention period 
without the written approval of the sponsor. No records may be transferred to another 
location or party without written notification to the sponsor. In the event of a conflict 
between this protocol and the fully executed clinical study agreement, the protocol 
shall prevail with respect to records retention. 
Additional information regarding remote data management and monitoring are provided 
in Section 10.17. 

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10.10.8. 
Source Documents 
• For this study, there will be source data recorded directly into the eCRF (i.e., no prior 
written or electronic record of data is available). 
• Source documents provide evidence for the existence of the participant and 
substantiate the integrity of the data collected. Source documents are filed at the 
investigator’s site. 
• Data reported in the eCRF that are transcribed from source documents must be 
consistent with the source documents or the discrepancies must be explained. The 
investigator may need to request previous medical records or transfer records, 
depending on the study. Also, current medical records must be available. 
• Definition of what constitutes source data and its origin can be found in the SRM. 
• The investigator must maintain accurate documentation (source data) that supports 
the information entered in the CRF. 
• Study monitors will perform ongoing source data verification to confirm that data 
entered into the CRF by authorized site personnel are accurate, complete, and 
verifiable from source documents; that the safety and rights of participants are being 
protected; and that the study is being conducted in accordance with the currently 
approved protocol and any other study agreements, ICH GCP, and all applicable 
regulatory requirements. 
10.10.9. 
Study and Site Start and Closure 
First Act of Recruitment 
The study start date is the date on which the clinical study’s first participant’s first visit 
(FSFV) occurs (i.e., the date the first participant is screened). 
Study/Site Termination 
GSK or designee reserves the right to close the study site or terminate the study at any 
time for any reason at the sole discretion of GSK. Study sites will be closed upon study 
completion. A study site is considered closed when all required documents and study 
supplies have been collected and a study-site closure visit has been performed. 
The investigator may initiate study-site closure at any time, provided there is reasonable 
cause and sufficient notice is given in advance of the intended termination. 
Reasons for the early closure of a study site by the sponsor or investigator may include 
but are not limited to the following: 
For study termination: 
• Discontinuation of further study treatment development. 

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For site termination: 
• Failure of the investigator to comply with the protocol, the requirements of the 
IRB/IEC or local health authorities, the sponsor’s procedures, or GCP guidelines 
• Inadequate or no recruitment of participants (evaluated after a reasonable amount of 
time) by the investigator 
• If the study is prematurely terminated or suspended, the sponsor shall promptly 
inform the investigators, the IRBs/IECs, the regulatory authorities, and any contract 
research organization(s) used in the study of the reason for termination or suspension, 
as specified by the applicable regulatory requirements. The investigator shall 
promptly inform the participant and should assure appropriate participant therapy 
and/or follow-up. 
10.10.10. Publication Policy 
GSK seeks to publish medically or scientifically significant results in searchable peer-
reviewed scientific literature within 18 months from LSLV. GSK follows International 
Committee of Medical Journal Editors standards for authorship and uses good 
publications practices to guide publications. 
• The results of this study may be published or presented at scientific meetings. If this 
is foreseen, the investigator agrees to submit all manuscripts or abstracts to the 
sponsor before submission. This allows the sponsor to protect proprietary information 
and to provide comments. 
• The sponsor will comply with the requirements for publication of study results. In 
accordance with standard editorial and ethical practice, the sponsor will generally 
support publication of multi-center studies only in their entirety and not as individual 
site data. In this case, a coordinating investigator will be designated by mutual 
agreement. 
• Authorship will be determined by mutual agreement and in line with International 
Committee of Medical Journal Editors authorship requirements. 

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10.11. 
Appendix 11: New York Heart Association Classification 
The New York Heart Association Functional Classification: Class I, II, III, or IV Heart 
Failure [Dolgin, 1994] provides a simple way of classifying the extent of heart failure. It 
places participants in 1 of 4 categories based on the level of limitation experienced during 
physical activity as follows: 
Class 
Symptoms 
Class I 
(Mild) 
No limitation of physical activity. Ordinary physical activity does not cause undue fatigue, 
palpitation, or dyspnea (shortness of breath). 
Class II 
(Mild) 
Slight limitation of physical activity. Comfortable at rest, but ordinary physical activity results 
in fatigue, palpitation, or dyspnea. 
Class III 
(Moderate) 
Marked limitation of physical activity. Comfortable at rest, but less than ordinary physical 
activity results in fatigue, palpitation, or dyspnea. 
Class IV 
(Severe) 
Unable to carry out any physical activity without discomfort. Symptoms of cardiac 
insufficiency at rest. If any physical activity is undertaken, discomfort is increased. 

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10.12. 
Appendix 12: Liver Safety Drug Restart or Rechallenge 
Guidelines 
• If participant meets liver chemistry stopping criteria, do not restart/rechallenge 
participant with study treatment unless all of the following criteria are met: 
• GlaxoSmithKline (GSK) approval is granted (see following description), and 
• Institutional Review Board (IRB) and/or Independent Ethics Committee (IEC) 
approval is obtained, if required, and 
• Separate consent for treatment restart/rechallenge is signed by the participant and the 
participant is informed of any associated risks. 
If GSK approval to restart/rechallenge participant with study treatment is not granted, 
then the participant must permanently discontinue study treatment and may continue in 
the study for protocol-specified follow-up assessments. 
Rechallenge After Liver Stopping Events that are Possibly Related to Study 
Treatment 
After drug-induced liver injury (DILI), drug rechallenge is associated with a 
13% mortality across all drugs in prospective studies [Andrade, 2009]. Clinical 
outcomes vary by drug, with nearly 50% fatality with halothane re-administered within 
1 month of initial injury. However, some drugs seldom result in recurrent liver injury or 
fatality. 
Risk factors for a fatal drug rechallenge outcome include the following: 
• Hypersensitivity with initial liver injury (e.g., fever, rash, eosinophilia) 
[Andrade, 2009] 
• Jaundice or bilirubin >2xupper limit of normal (ULN) with initial liver injury (direct 
bilirubin >35% of total) 
• Ongoing severe liver injury defined by ALT >3xULN, bilirubin >2xULN (direct 
bilirubin >35% of total), or international normalized ratio >1.5 
• Serious adverse event or fatality has earlier been observed with drug rechallenges 
[Hunt, 2010; Papay, 2009] 
• Evidence of drug-related non-clinical liability (e.g., reactive metabolites, 
mitochondrial impairment) [Hunt, 2010]. 
Rechallenge refers to resuming study treatment after DILI. Because of the risks 
associated with rechallenge after DILI, this should only be considered for a participant 
for whom there is compelling evidence of benefit from a critical or life-saving medicine, 
there is no alternative approved medicine available, and a benefit/risk assessment of 
rechallenge is considered to be favorable. 

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Approval by GSK for rechallenge with study treatment can be considered when the 
following criteria are met: 
• Principal investigator requests consideration of rechallenge with study treatment for a 
participant who is receiving compelling benefit with study treatment that exceeds 
risk, and no effective alternative therapy is available 
• IRB/IEC approval for rechallenge with study treatment must be obtained, as required 
If the rechallenge is approved by GSK in writing: 
• The participant must be provided with a clear description of the possible benefits and 
risks of study treatment administration, including the possibility of recurrent, more 
severe liver injury or death 
• The participant must also provide signed informed consent specifically for the 
rechallenge with study treatment. Documentation of informed consent must be 
recorded in the study file. 
• Study treatment must be administered at the dose specified by GSK 
• Participants approved by GSK for rechallenge with study treatment must return to the 
clinic twice a week for liver chemistry tests until stable liver chemistries have been 
demonstrated and then standard laboratory monitoring may resume as per protocol 
• If, after study treatment rechallenge, the participant meets protocol-defined liver 
chemistry stopping criteria, study treatment should be permanently discontinued 
• GSK Medical Director and the IRB/IEC must be informed of the participant’s 
outcome after study treatment rechallenge 
• GSK must be notified of any adverse events, as per Section 8.4 and Section 10.14 
Restart After Transient Resolving Liver Stopping Events Not Related to Study 
Treatment 
Restart refers to resuming study treatment after liver stopping events in which there is a 
clear underlying cause (other than DILI) of the liver event (e.g., biliary obstruction, 
pancreatic events, hypotension, acute viral hepatitis). Furthermore, restart is not permitted 
following a liver stopping event when the underlying cause was alcohol-related hepatitis. 
Approval by GSK for study treatment restart can be considered when the following 
criteria are met: 
• Principal investigator requests consideration for study treatment restart if liver 
chemistries have a clear underlying cause (e.g., biliary obstruction, hypotension, and 
liver chemistries have improved to normal or are within 1.5×baseline and ALT 
<3×ULN) 
• Possible study treatment-induced liver injury has been excluded by the principal 
investigator and the study team. This includes the absence of markers of 
hypersensitivity (otherwise unexplained fever, rash, eosinophilia). Where a study 
treatment has an identified genetic marker associated with liver injury (e.g., lapatinib, 

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abacavir, amoxicillin/clavulanate), the presence of the marker should be excluded. If 
study treatment-related liver injury cannot be excluded, the guidance on rechallenge 
will apply (Section 7.1.5) 
• There is no evidence of alcohol-related hepatitis 
• IRB/IEC approval of study treatment restart must be obtained, as required 
If restart of study treatment is approved by GSK in writing: 
• The participant must be provided with a clear description of the possible benefits and 
risks of study treatment administration, including the possibility of recurrent, more 
severe liver injury or death 
• The participant must also provide signed informed consent specifically for the study 
treatment restart. Documentation of informed consent must be recorded in the study 
file. 
• Study treatment must be administered at the dose specified by GSK 
• Participants approved by GSK for restart of study treatment must return to the clinic 
once a week for liver chemistry tests until stable liver chemistries have been 
demonstrated and then standard laboratory monitoring may resume as per protocol 
• If a participant meets protocol-defined liver chemistry stopping criteria after study 
treatment restart, the study treatment should be permanently discontinued 
• GSK Medical Director and the IRB/IEC must be informed of the participant’s 
outcome after study treatment restart 
• GSK must be notified of any adverse events, as per Section 8.4 and Section 10.14 
 

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10.13. 
Appendix 13: Clinical Laboratory Tests 
A list of clinical laboratory tests required during the study is included in Table 20. See 
the SoA (Section 1.3) for the timing and frequency. 
Protocol-specific requirements for inclusion or exclusion of participants are detailed in 
Section 5. 
Additional tests may be performed at any time during the study as determined necessary 
by the investigator or required by local regulations. 
Investigators must document their review of each laboratory safety report. 
Table 20 
Protocol-Required Clinical Laboratory Tests 
Hematology1,2 
• 
Platelet count 
• 
RBC count 
• 
WBC count 
(absolute) 
 
• 
Hemoglobin 
• 
Hematocrit 
RBC Indices: 
• 
MCV 
• 
MCH 
• 
MCHC 
Automated WBC 
Differential (%) or Absolute: 
• 
Neutrophils 
• 
Lymphocytes 
• 
Monocytes 
• 
Eosinophils 
• 
Basophils 
Clinical Chemistry1,2 
• 
BUN 
• 
Creatinine 
• 
Glucose 
• 
Sodium  
• 
Magnesium 
• 
Potassium 
• 
Chloride 
• 
Carbon dioxide 
(CO2 or bicarbonate) 3 
• 
Calcium 
• 
Phosphorous 
• 
AST 
• 
ALT 
• 
GGT 
• 
ALP 
• 
CK 
• 
Total and direct 
bilirubin 
• 
Uric acid 
• 
Albumin 
• 
Total protein 
• 
LDH 
Urine Tests 
• 
Urinalysis1,2 
o Specific gravity, pH, glucose, protein, blood, and ketones by dipstick 
o Microscopic examination (if blood or protein is detected by dipstick) 
• 
Spot urine (ACR)4,5 
Other Laboratory Tests 
• 
eGFR1 
• 
HBsAg5; HBcAb5, HCAb1, HBV DNA5 (see note), HCV RNA5 (see note) 
Note: HBV DNA testing must be done to determine participant eligibility if HBsAg+ or HBcAb+ 
Note: HCV RNA testing must be done to determine participant eligibility if HCAb+ 
• 
Pregnancy test (urine or serum)1;FSH1, and estradiol1 (as needed in WONCBP only) 
Disease Evaluation Laboratory Tests6 
• 
2-microglobulin 
• 
UPEP (on 24 h urine collection), urine immunofixation (urine M protein calculation) 
• 
SPEP; serum immunofixation (serum M protein calculation) 
• 
Serum kappa, lambda FLC, FLC ratio 
• 
IgG, IgM, IgA, IgD/IgE7 
• 
Calcium corrected for albumin (serum) 

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Bone Marrow Aspiration/Biopsy 
• 
BM aspirate and/or biopsy for disease assessments (screening, CR, and PD [only if PD not evident 
otherwise])1 
• 
BM aspirate for FISH testing5,8 
• 
BM aspirate and/or biopsy for BCMA expression and biomarker research6 
• 
BM biopsy to confirm sCR (by IHC)5 
PK and ADA6 
• 
Samples for belantamab mafodotin PK analysis (cys-MMAF and ADC) 
• 
Samples for anti-belantamab mafodotin antibody analysis (immunogenicity) 
Biomarker Measurements6 
• 
sBCMA (serum) 
• 
TBNK panel (whole blood) 
Optional Laboratory Tests 
• 
Genetic Sample9 
Abbreviations: ACR=albumin/creatinine ratio; ADA=anti-drug antibody; ALP=alkaline phosphatase; ALT=alanine 
aminotransferase; AST=aspartate aminotransferase; BCMA-B-cell maturation antigen; BM=bone marrow; 
BUN=blood urea nitrogen; CK=creatine kinase; CO2=carbon dioxide; eGFR=estimated glomerular filtration rate; 
FISH=fluorescence-in-situ hybridization; FLC=free light chain; FSH=follicle-stimulating hormone; 
GGT=gamma-glutamyl transferase; HBsAg=hepatitis B surface antigen; HBcAb=hepatitis B core antibody; 
HCAb=hepatitis C antibody; HCV=hepatitis C virus; Ig=immunoglobulin; LDH=lactate dehydrogenase; 
MCH=mean corpuscular hemoglobin; MCHC=mean corpuscular hemoglobin concentration; MCV=mean 
corpuscular volume; PD=progressive disease; PK=pharmacokinetic(s); RBC=red blood cell; sBCMA=soluble 
B-cell maturation antigen; sCR=stringent complete response; SPEP=serum protein electrophoresis; TBNK=T, B, 
and natural killer cells; UPEP=urine protein electrophoresis; WBC=white blood cell; WONCBP=women of 
nonchildbearing potential. 
1. 
To be performed at local laboratory.  
2. 
Hematology, clinical chemistry, and urinalysis should be performed and reviewed 72 hours prior to dosing. 
3. 
Performed only if considered local standard of care. 
4. 
ACR (spot urine preferably from first void). Urine dipstick for protein may be used to assess for presence of urine 
protein. ACR must be collected at screening and thereafter to be done in any participant with urine dipstick result 
of ≥2+ (during study treatment), or with positive protein if urine dipstick protein quantification is not available. ACR 
will be performed at a local laboratory. If local testing is not available, then central testing will be performed. 
5. 
If not available locally, can be performed centrally. 
6. 
To be performed at central laboratory.  
7. 
Only for participants with IgD/E myeloma. 
8. 
FISH testing at least for: t(4;14), t(14;16), amp(1q), del(1p) and del(17p13). If participant is known to have tested 
positive for t(4;14) or t(14/16) on previous tests regardless of time frame, FISH for these translocations does not 
need to be repeated. FISH results for amp(1q), del(1p) and del(17p13) from samples taken within 60 days before 
the first dose are acceptable. 
9. 
Informed consent for optional sub-studies (e.g., genetic research) must be obtained once the participant meets all 
eligibility criteria before collecting a sample. 

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10.14. 
Appendix 14: Adverse Events and Serious Adverse Events: 
Definitions and Procedures for Recording, Evaluating, 
Follow-up, and Reporting 
10.14.1. 
Definition of Adverse Event 
AE Definition 
• 
An adverse event (AE) is any untoward medical occurrence in a clinical study participant, temporally 
associated with the use of a study treatment, whether or not considered related to the study 
treatment. 
Note: An AE can therefore be any unfavorable and unintended sign (including an abnormal 
laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of 
a study treatment. 
Events Meeting the AE Definition 
• 
Any abnormal laboratory test results (hematology, clinical chemistry, or urinalysis) or other safety 
assessments (e.g., electrocardiogram, radiological scans, vital signs measurements), including those 
that worsen from baseline considered clinically significant in the medical and scientific judgment of 
the investigator (i.e., not related to progression of underlying disease). 
• 
Exacerbation of a chronic or intermittent pre-existing condition including either an increase in 
frequency and/or intensity of the condition. 
• 
New condition detected or diagnosed after study treatment administration even though it may have 
been present before the start of the study. 
• 
Signs, symptoms, or the clinical sequelae of a suspected treatment-treatment interaction. 
• 
Signs, symptoms, or the clinical sequelae of a suspected overdose of either study treatment or a 
concomitant medication. Overdose per se will not be reported as an AE/serious adverse event (SAE) 
unless it is an intentional overdose taken with possible suicidal/self-harming intent. Such overdoses 
should be reported regardless of sequelae. 
• 
“Lack of efficacy” or “failure of expected pharmacological action” per se will not be reported as an AE 
or SAE. Such instances will be captured in the efficacy assessments. However, the signs, 
symptoms, and/or clinical sequelae resulting from lack of efficacy will be reported as AE or SAE if 
they fulfill the definition of an AE or SAE. 
Events NOT Meeting the AE Definition  
• 
Any clinically significant abnormal laboratory findings or other abnormal safety assessments that are 
associated with the underlying disease, unless judged by the investigator to be more severe than 
expected for the participant’s condition. 
• 
The disease/disorder being studied or expected progression, signs, or symptoms of the 
disease/disorder being studied, unless more severe than expected for the participant’s condition. 
• 
Medical or surgical procedure (e.g., endoscopy, appendectomy): the condition that leads to the 
procedure is the AE. 
• 
Situations in which an untoward medical occurrence did not occur (social and/or convenience 
admission to a hospital). 
• 
Anticipated day-to-day fluctuations of pre-existing disease(s) or condition(s) present or detected at 
the start of the study that do not worsen. 

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10.14.2. 
Definition of Serious Adverse Event 
An SAE is defined as any untoward medical occurrence that, at any dose, meets one or more of 
the following criteria: 
a. Results in death 
b. Is life-threatening 
The term “life-threatening” in the definition of “serious” refers to an event in which the participant was at 
risk of death at the time of the event. It does not refer to an event which, hypothetically, might have 
caused death if it were more severe. 
c. Requires inpatient hospitalization or prolongation of existing hospitalization 
• 
In general, hospitalization signifies that the participant has been admitted (usually involving at 
least an overnight stay) at the hospital or emergency ward for observation and/or treatment that 
would not have been appropriate in the physician’s office or outpatient setting. Complications 
that occur during hospitalization are an AE. If a complication prolongs hospitalization or fulfills 
any other serious criteria, the event is serious. When in doubt as to whether “hospitalization” 
occurred or was necessary, the AE should be considered serious. 
• 
Hospitalization for elective treatment of a pre-existing condition that did not worsen from 
baseline is not considered an AE. 
d. Results in persistent or significant disability/incapacity 
• 
The term disability means a substantial disruption of a person’s ability to conduct normal life 
functions. 
• 
This definition is not intended to include experiences of relatively minor medical significance 
such as uncomplicated headache, nausea, vomiting, diarrhea, influenza, and accidental trauma 
(e.g., sprained ankle) that may interfere with or prevent everyday life functions, but do not 
constitute a substantial disruption. 
e. Is a congenital anomaly/birth defect 
f. 
Other situations: 
• 
Possible Hy’s law case: alanine aminotransferase ≥3x upper limit of normal (ULN) and total 
bilirubin ≥2xULN (>35% direct bilirubin) or international normalized ratio >1.5 must be reported 
as an SAE. 
• 
Medical or scientific judgment should be exercised by the investigator in deciding whether SAE 
reporting is appropriate in other situations such as significant medical events that may 
jeopardize the participant or may require medical or surgical intervention to prevent one of the 
other outcomes listed in the above definition. These events should usually be considered 
serious. 
• 
Examples of such events include invasive or malignant cancers, intensive treatment for allergic 
bronchospasm, blood dyscrasias, convulsions, or development of treatment dependency or 
treatment abuse. 
10.14.3. 
Definition of Cardiovascular Events 
Cardiovascular Events (CV) Definition: 
Investigators will be required to fill out the specific CV event page of the electronic Case Report Form 
(eCRF) for the following AEs and SAEs: 
• 
Myocardial infarction/unstable angina 
• 
Congestive heart failure 
• 
Arrhythmias 
• 
Valvulopathy 
• 
Pulmonary hypertension 
• 
Cerebrovascular events/stroke and transient ischemic 
attack 
• 
Peripheral arterial thromboembolism 
• 
Deep venous thrombosis/pulmonary 
embolism 
• 
Revascularization 

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10.14.4. 
Recording and Follow-Up of Adverse Events and Serious 
Adverse Events 
Recording of AEs and SAEs 
• 
When an AE/SAE occurs, it is the responsibility of the investigator to review all documentation (e.g., 
hospital progress notes, laboratory results, and diagnostics reports) related to the event. 
• 
The investigator will then record all relevant AE/SAE information. 
• 
It is not acceptable for the investigator to send photocopies of the participant’s medical records to 
GlaxoSmithKline (GSK) in lieu of completion of the GSK required form. 
• 
There may be instances when copies of medical records for certain cases are requested by GSK. In this 
case, all participant identifiers, with the exception of the participant number, will be redacted on the copies 
of the medical records before submission to GSK. 
• 
The investigator will attempt to establish a diagnosis of the event based on signs, symptoms, and/or other 
clinical information. Whenever possible, the diagnosis (not the individual signs/symptoms) will be 
documented as the AE/SAE. 
Assessment of Intensity 
The investigator will make an assessment of intensity for each AE and SAE reported during the study and 
assign it to one of the following categories: 
• 
Mild: Asymptomatic or mild symptoms; clinical or diagnostic observations only; intervention not indicated. 
• 
Moderate: Minimal, local, or noninvasive intervention indicated; limiting age-appropriate instrumental 
Activities of Daily Living (ADL). Instrumental ADL refers to preparing meals, shopping for groceries or 
clothes, using the telephone, managing money, etc. 
• 
Severe: Severe or medically significant but not immediately life-threatening; hospitalization or 
prolongation of hospitalization indicated; disabling, limiting self-care ADL. Self-care ADL refers to bathing, 
dressing and undressing, feeding self, using the toilet, taking medications, and not bedridden. 
Assessment of Causality 
The investigator is obligated to assess the relationship between study treatment and each occurrence of each 
AE/SAE. The investigator will use clinical judgment to determine the relationship. 
• 
A reasonable possibility of a relationship conveys that there are facts, evidence, and/or arguments to 
suggest a causal relationship, rather than a relationship cannot be ruled out. 
• 
Alternative causes, such as underlying disease(s), concomitant therapy, and other risk factors, as well as 
the temporal relationship of the event to study treatment administration, will be considered and 
investigated. 
• 
The investigator will also consult the Investigator’s Brochure and/or Product Information, for marketed 
products, in his/her assessment. 
• 
For each AE/SAE, the investigator must document in the medical notes that he/she has reviewed the 
AE/SAE and has provided an assessment of causality. 
• 
There may be situations in which an SAE has occurred, and the investigator has minimal information to 
include in the initial report to GSK. However, it is very important that the investigator always make an 
assessment of causality for every event before the initial transmission of the SAE data to GSK. 
• 
The investigator may change his/her opinion of causality in light of follow-up information and send an SAE 
follow-up report with the updated causality assessment. 
• 
The causality assessment is one of the criteria used when determining regulatory reporting requirements. 
Follow-up of AEs and SAEs 
• 
The investigator is obligated to perform or arrange for the conduct of supplemental measurements and/or 
evaluations as medically indicated or as requested by GSK to elucidate the nature and/or causality of the 
AE or SAE as fully as possible. This may include additional laboratory tests or investigations, 
histopathological examinations, or consultation with other health care professionals. 
• 
New or updated information will be recorded in the originally submitted documents. 
• 
The investigator will submit any updated SAE data to GSK within 24 hours of receipt of the information. 

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10.14.5. 
Reporting of Serious Adverse Events to GlaxoSmithKline 
SAE Reporting to GSK via Electronic Data Collection Tool 
• 
The primary mechanism for reporting an SAE to GSK will be the electronic data collection tool. 
• 
If the electronic system is unavailable, then the site will use the paper SAE data collection tool (see 
next section) to report the event within 24 hours. 
• 
The site will enter the SAE data into the electronic system as soon as it becomes available. 
• 
After the study is completed at a given site, the electronic data collection tool will be taken offline to 
prevent the entry of new data or changes to existing data. 
• 
If a site receives a report of a new SAE from a study participant or receives updated data on a 
previously reported SAE after the electronic data collection tool has been taken offline, then the site 
can report this information on a paper SAE form (see next section) or to the GSK Medical 
Director/SAE Coordinator by telephone. 
• 
Contacts for SAE reporting can be found in the Study Reference Manual (SRM). 
SAE Reporting to GSK via Paper Data Collection Tool 
• 
Facsimile transmission of the SAE paper data collection tool is the preferred method to transmit this 
information to the GSK Medical Director/SAE Coordinator. 
• 
In rare circumstances and in the absence of facsimile equipment, notification by telephone is 
acceptable with a copy of the SAE data collection tool sent by overnight mail or courier service. 
• 
Initial notification via telephone does not replace the need for the investigator to complete and sign 
the SAE data collection tool within the designated reporting time frames. 
• 
Contacts for SAE reporting can be found in the SRM. 

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10.15. 
Appendix 15: Genetics 
USE/ANALYSIS OF DNA 
• 
Genetic variation may impact a participant’s response to study treatment, 
susceptibility, severity, and progression of disease. Variable response to study 
treatment may be due to genetic determinants that impact drug absorption, 
distribution, metabolism, and excretion; mechanism of action of the drug; disease 
etiology; and/or molecular subtype of the disease being treated. Therefore, where 
local regulations and IRB/IEC allow, a blood sample will be collected for 
deoxyribonucleic acid (DNA) analysis. 
• 
DNA samples will be used for research related to belantamab mafodotin or MM and 
related diseases. They may also be used to develop tests/assays (including diagnostic 
tests) related to belantamab mafodotin or study treatments of this drug class, and 
MM. Genetic research may consist of the analysis of 1 or more candidate genes or 
the analysis of genetic markers throughout the genome or analysis of the entire 
genome (as appropriate). 
• 
DNA samples will be analyzed for relationships between genetic variants in the host 
and response to belantamab mafodotin. A detailed description of any planned 
analyses will be documented in a Statistical Analysis Plan (SAP) before initiation of 
analyses. Planned analyses and results of genetic investigations will be reported 
either as part of the clinical SAP and CSR, or in a separate genetics SAP and report, 
as appropriate. 
• 
The samples may be analyzed as part of a multi-study assessment of genetic factors 
involved in the response to belantamab mafodotin or study interventions of this 
class. The results of genetic analyses may be reported in the CSR or in a separate 
study summary. 
• 
The sponsor will store the DNA samples in a secure storage space with adequate 
measures to protect confidentiality. 
• 
The samples will be retained while research on belantamab mafodotin (or study 
treatments of this class) or MM continues, but no longer than 15 years after the last 
participant’s last visit or other period as per local requirements. 

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10.16. 
Appendix 16: Operating Characteristics of the Safety 
Stopping Rule for Arm E 
 

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10.17. 
Appendix 17: Data Management/Monitoring 
Source Data Verification/Source Document Review (SDV/SDR) 
During periods in which on-site monitoring is not permitted, GlaxoSmithKline (GSK) 
will consider remote Source Data Verification/Source Document Review (SDV/SDR) 
where permitted by the clinical site/institution and in accordance with local law and 
regulatory guidance documents. 
Remote SDV/SDR will be proposed to study sites to meet a participant and/or critical 
data quality need, e.g., to assess participant safety or to ensure data integrity. The study 
specific monitoring plan will be updated in accordance with remote monitoring practices 
adopted for the country/study. The Informed Consent Form will be updated in line with 
local regulations to permit remote monitoring practices. In case of remote SDV/SDR, 
GSK will work with the site to ensure participant privacy. 
Electronic Case Report Form Final or Interim Sign-Off Process 
The principal investigator is responsible for ensuring that the data within the electronic 
Case Report Form (eCRF) casebook and any other data sources utilized during the study 
for each study participant is complete and consistent with source documents throughout 
the study (ICH GCP 4.9.1 and 4.9.2). The principal investigator may sign/re-sign the 
eCRF from any computer/location by accessing the electronic data capture platform) 
using his/her unique eCRF login credentials. 
Essential Document Sign-Off Process 
If an investigator is unable to print and sign essential documents such as 
Protocol/Amendment signature page, then Email approval can be accepted by replying to 
the relevant email that is sent by GSK. Note that unblinding procedures remain the same 
as those documented in the protocol and other study-related documents. 

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10.18. 
Appendix 18: Progression-Free Survival Event and 
Censoring Rules 
Situation 
Date of Event 
(Progression/Death) or Censoreda  
Event 
(Progression/Death) or Censored 
No adequate baseline 
assessments and the 
participant has not died (if 
the participant has died, 
follow the rules for death 
indicated at the bottom of 
the table) 
Randomization 
Censored 
No post-baseline 
assessments and the 
participant has not died (if 
the participant has died, 
follow the rules for death 
indicated at the bottom of 
the table) 
Randomization 
Censored 
PD documented between 
scheduled visits and 
progression documented 
without extended loss-to-
follow-up timee 
Date of assessment of PDb 
(1) min (Date of next scheduled visit, 
date of death) 
Event 
(1) Event 
With post-baseline 
assessment but no PD (or 
death)  
Date of last “adequate” assessment of 
responsec 
Censored 
No adequate post-baseline 
assessment before start of 
new anti-myeloma therapy 
Randomization  
Censored 
With adequate post-baseline 
assessment and new 
anti-myeloma therapy 
started (before documented 
PD).d 
Date of last “adequate” assessment of 
responsec (on or before starting 
anti-myeloma therapy) 
(1) Date of starting new anti-myeloma 
therapy 
Censored 
(1) Event 
Death before first scheduled 
assessment (or death at 
baseline or without any 
adequate assessments) 
Date of death 
Event 
Death between adequate 
assessment visits  
Date of death 
Event 

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Situation 
Date of Event 
(Progression/Death) or Censoreda  
Event 
(Progression/Death) or Censored 
Death or PD after missing 
2 or more scheduled 
assessments 
Date of last “adequate” assessment of 
responseb (before missed 
assessments): since disease 
assessment is every 3 weeks, a window 
of 49 days (6 weeks + 7-day window) 
will be used to determine whether there 
is extended time without adequate 
assessment. If the time difference 
between PD or death and last adequate 
disease assessment is more than 
49 days, PFS will be censored at the 
last adequate disease assessment 
before PD or death. 
(1) Date of death or progression 
Censored 
(1) Event 
(1) Treatment 
discontinuation due to 
clinical PD before PD or 
death 
(1) Date of treatment discontinuation 
(1) Event 
Abbreviations: CR=complete response; FLC=free light chain; MR=minimal response; PD=progressive disease; 
PEP=protein electrophoresis; PFS=progression-free survival; PR=partial response; sCR=stringent complete 
response; SD=stable disease; VGPR=very good partial response. 
Note: (1) Rules to be applied for PFS sensitivity analysis. 
a. 
Event or censored are based on confirmed responses. 
b. 
The earliest of (i) Date of serum/urine PEP test (if progression is based on increase in serum or urine M protein); 
or (ii) Date of radiological assessment of extramedullary disease (if progression is based on increase in the size of 
existing plasmacytoma or appearance of new soft tissue plasmacytoma, or (iii) Date of last radiological 
assessment of bone lesions (if progression is based on increase in the size of existing bone lesions or 
appearance of new bone lesions), or (iv) Date of laboratory test for FLC (if progression is based on increase of 
difference between involved and uninvolved FLCs). 
c. 
An adequate assessment is defined as an assessment where the response is sCR, CR, PR, VGPR, MR, or SD. 
d. 
If PD and new anti-myeloma therapy occur on the same day, assume the progression was documented first (e.g., 
the outcome is progression and the date is the date of the assessment of progression). 
e. 
Extended loss-to-follow-up time = 6 weeks + 7 day window = 49 day window; Without extended loss-to-follow-up 
time is defined as:  49 days; after an extended loss-to-follow-up time is defined as: >49 days. 

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10.19. 
Appendix 19: Visual Acuity Conversion 
Snellen 
Snellen (Metric) 
logMAR 
Decimal 
No light perceptiona 
No light perception 
4.0 
No light perception 
Light perceptiona 
Light perception 
3.9 
Light perception 
Hand motionb, or 20/20,000 
Hand motion, or 60/6,000 
3.0 
0.001 
Counts fingersc, or 20/2,000 
Counts fingers, or 60/600 
2.0 
0.01 
20/800 
6/240 
1.6 
0.025 
20/640 
6/200 
1.5 
0.03 
20/500 
6/150 
1.4 
0.04 
20/400 
6/120 
1.3 
0.05 
20/320 
6/96 
1.2 
0.06 
20/250 
6/76 
1.1 
0.08 
20/200 
6/60 
1.0 
0.10 
20/160 
6/48 
0.9 
0.13 
20/150 
6/45 
0.9d 
0.13 
20/125 
6/38 
0.8 
0.16 
20/100 
6/30 
0.7 
0.20 
20/80 
6/24 
0.6 
0.25 
20/70 
6/21 
0.5d 
0.29 
20/63 
6/20 
0.5 
0.32 
20/60 
6/18 
0.5d 
0.33 
20/50 
6/15 
0.4 
0.40 
20/40 
6/12 
0.3 
0.50 
20/32 
6/10 
0.2 
0.63 
20/30 
6/9 
0.2d 
0.67 
20/25 
6/7.5 
0.1 
0.80 
20/20 
6/6 
0.0 
1.00 
20/16 
6/5 
-0.1 
1.25 
20/15 
6/4.5 
-0.1d 
1.33 
20/12.5 
6/3.5 
-0.2 
1.6 
20/10 
6/3 
-0.3 
2.0 
Source: Adapted from Holladay, 2004 
Abbreviation: logMAR=logarithm of the minimum angle of resolution. 
a. 
“Light perception” or “no light perception” do not have corresponding Snellen or decimal values 
b. 
Hand motion at 2 feet 
c. 
Counting fingers at 2 feet 
d. 
Values that are not in logMAR steps such as 20/150 are included because of their common appearance in older 
visual acuity charts. Values are rounded to the nearest decimal to keep measures to a single decimal place. 

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10.20. 
Appendix 20: Abbreviations,Trademarks and Definitions of 
Terms 
ACR 
albumin/creatinine ratio 
ADA 
anti-drug antibody 
ADC 
antibody-drug conjugate 
ADCC 
antibody dependent cellular cytotoxicity 
ADCP 
antibody dependent cellular phagocytosis 
AE 
adverse event 
AESI 
adverse event of special interest 
ALP 
alkaline phosphatase 
ALT 
alanine aminotransferase 
ART 
anti-retroviral therapy 
AST 
aspartate aminotransferase 
AUC 
area under the concentration-time curve 
AxMP 
auxiliary medicinal product 
BCMA 
B-cell maturation antigen 
BCVA 
best corrected visual acuity 
BM 
bone marrow 
BP 
blood pressure 
Cavg 
average concentration 
cfDNA 
circulating plasma cell-free DNA 
CFR 
Code of Federal Regulations 
CI 
confidence interval 
CIOMS 
Council for International Organizations of Medical Sciences 
CK 
creatine kinase 
CL 
clearance 
CLW 
Central Laboratory Worksheet 
Cmax 
maximum concentration 
CONSORT 
Consolidated Standards of Reporting Trials 
CR 
complete response 
CSR 
Clinical Study Report 
CT 
computed tomography 
Ctau 
concentration at the end of the dosing interval 
CTCAE 
Common Terminology Criteria for Adverse Events 
CTFG 
Clinical Trial Facilitation Group 
CV 
cardiovascular 
cys-mcMMAF 
cysteine-maleimidocaproyl monomethyl auristatin F 
ΔlogMAR 
change in logarithm of the minimum angle of resolution 
DILI 
drug-induced liver injury 
DNA 
deoxyribonucleic acid 
DoR 
duration of response 
DRE 
disease-related event 
ECG 
electrocardiogram 
ECOG 
Eastern Cooperative Oncology Group 
eCRF 
electronic Case Report Form 
eGFR 
estimated glomerular filtration rate 
EMA 
European Medicines Agency 
EMD 
extramedullary disease 
EOI 
end of infusion 

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EORTC-QLQ-C30 
European Organisation for Research and Treatment of Cancer Quality of Life 
Questionnaire 30-Item Core Module 
EORTC-QLQ-MY20 
European Organisation for Research and Treatment of Cancer Quality of Life 
Questionnaire 20-item Multiple Myeloma Module 
EOT 
end of treatment 
FACT-GP5 
Functional Assessment of Cancer Therapy – General Population 
FDA 
Food and Drug Administration 
FISH 
fluorescence-in-situ hybridization 
FLC 
free light chain 
FSFV 
first participant’s first visit 
FSH 
follicle-stimulating hormone 
FTIH 
first time in human 
GCP 
good clinical practice 
GGT 
gamma glutamyl transferase 
GSK 
GlaxoSmithKline 
HBcAb 
hepatitis B core antibody 
HBsAg 
hepatitis B surface antigen 
HBV 
hepatitis B virus 
HCAb 
hepatitis C antibody 
HCV 
hepatitis C virus 
HIV 
human immunodeficiency virus 
HR 
heart rate 
HRQoL 
health-related quality of life 
HRT 
hormone replacement therapy 
ICF 
Informed Consent Form 
ICH 
International Council for Harmonisation of Technical Requirements for 
Pharmaceuticals for Human Use 
IDMC 
Independent Data Monitoring Committee 
IEC 
Independent Ethics Committee 
Ig 
immunoglobulin 
IHC 
immunohistochemistry 
IMP 
investigational medicinal product 
IMWG 
International Myeloma Working Group 
INR 
international normalized ratio 
IP 
Investigational Product 
IRB 
Institutional Review Board 
IRR 
infusion-related reaction 
IRT 
interactive response technology 
ISS 
International Staging System 
ITT 
Intent-to-Treat 
IUD 
intrauterine device 
IUS 
intrauterine hormone-releasing system 
IV 
intravenous 
KVA 
keratopathy visual acuity 
LAM 
lactational amenorrhea method 
LDH 
lactate dehydrogenase 
LFT 
liver function test 
LSFD 
time the last participant receives their first dose of study treatment 
mAb 
monoclonal antibody 
MDRD 
Modified Diet in Renal Disease 

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MedDRA 
Medical Dictionary for Regulatory Activities 
MM 
multiple myeloma 
MMAF 
monomethyl auristatin F 
MR 
minimal response 
MRI 
magnetic resonance imaging 
MRP 
multidrug resistance associated proteins 
NCI-CTCAE 
National Cancer Institute Common Terminology Criteria for Adverse Events 
NE 
not estimable 
NGS 
next generation sequencing 
NIMP 
non-investigational medicinal product 
NR 
not reached 
OATP 
organic anion transporting polypeptide 
ORR 
overall response rate 
OS 
overall survival 
OSDI 
Ocular Surface Disease Index 
OU 
both eyes 
P-gp 
P-glycoprotein 
PACT 
Post Analysis Continued Treatment 
PD 
progressive disease 
PET 
positron emission tomography 
PFS 
progression-free survival 
PGIC 
Patient Global Impression of Change 
PGIS 
Patient Global Impression of Severity 
PK 
pharmacokinetic(s) 
POEMS 
polyneuropathy, organomegaly, endocrinopathy, myeloma protein, and 
skin changes 
PR 
partial response 
PRO 
patient-reported outcome 
PRO-CTCAE 
Patient-Reported Outcomes version of the Common Terminology Criteria for 
Adverse Events 
Q3W 
every 3 weeks 
Q6W 
every 6 weeks 
Q9W 
every 9 weeks 
Q12W 
every 12 weeks 
QTc 
corrected QT interval 
QTcF 
QT interval corrected using Fridericia’s formula 
QTL 
quality tolerance limit 
RD 
lenalidomide plus low-dose dexamethasone 
RVD 
lenalidomide plus low-dose dexamethasone and bortezomib 
RNA 
ribonucleic acid 
RRMM 
relapsed or refractory multiple myeloma 
SAE 
serious adverse event 
SAP 
Statistical Analysis Plan 
sBCMA 
soluble B-cell maturation antigen 
sCR 
stringent complete response 
SCT 
stem cell transplantation 
SD 
stable disease 
SDV/SDR 
Source Data Verification/Source Document Review 
SoA 
Schedule of Activities 
SOC 
system organ class 

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SOI 
start of infusion 
SPEP 
serum protein electrophoresis 
SPK 
superficial punctate keratitis 
SRM 
Study Reference Manual 
TBNK 
T, B, and natural killer cells 
SUSAR 
suspected unexpected serious adverse reactions 
tmax 
time taken to reach maximum concentration 
ToxT 
toxicity over time 
TTP 
time to progression 
TTR 
time to response 
ULN 
upper limit of normal 
UPEP 
urine protein electrophoresis 
US 
United States 
V 
volume of distribution 
VCD 
bortezomib, cyclophosphamide, and dexamethasone 
VD 
bortezomib-dexamethasone 
VGPR 
very good partial response 
Vss 
volume of distribution at steady-state 
WOCBP 
woman/women of childbearing potential 
WONCBP 
woman/women of nonchildbearing potential 
Trademark Information 
Trademarks of the GlaxoSmithKline group 
of companies 
 
Trademarks not owned by the 
GlaxoSmithKline group of companies 
BLENREP 
 
MedDRA 
 
 
RandALL NG 
 
Term 
Definition 
Caregiver 
A ‘caregiver’ is someone who: 
lives in the close surroundings of a participant and has a continuous caring 
role or 
has substantial periods of contact with a participant and is engaged in their 
daily health care (e.g., a relative of the participant, a nurse who helps with 
daily activities in case of residence in a nursing home). 
In the context of a clinical study, a caregiver could include an individual 
appointed to oversee and support the participant's compliance with 
protocol specified procedures. 
Combination product 
Combination product comprises any combination of: 
drug 
device 
biological product. 
Each drug, device, and biological product included in a combination 
product is a constituent part. 
Eligible 
Qualified for enrollment into the study based upon strict adherence to 
inclusion/exclusion criteria 
Essential documents 
Documents that individually and collectively permit evaluation of the 
conduct of a study and the quality of the data produced 

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Term 
Definition 
Investigational Product 
A pharmaceutical form of an active substance or placebo being tested or 
used as a reference in a clinical trial, including products already with a 
marketing authorization but used or assembled (formulated or packaged) 
in a way different from the authorized form, or when used for an 
unauthorized indication, or when used to gain further information about the 
authorized form 
IMP 
A pharmaceutical form of an active substance or placebo being tested or 
used as a reference in a clinical trial, including products already with a 
marketing authorization but used or assembled (formulated or packaged) 
in a way different from the authorized form, or when used for an 
unauthorized indication, or when used to gain further information about the 
authorized form. 
Investigator 
A person responsible for the conduct of the clinical study at a study site. If 
a study is conducted by a team of individuals at a study site, the 
investigator is the responsible leader of the team and may be called the 
principal investigator. 
The investigator can delegate study-related duties and functions 
conducted at the study site to qualified individual(s) or party(ies) to perform 
those study-related duties and functions. 
Participant 
Term used throughout the protocol to denote an individual who has been 
contacted to participate or who participates in the clinical study as a 
recipient of the study intervention vaccine[s]/product[s]/control). 
Synonym: subject 
Randomization 
Process of random attribution of intervention to participants to reduce 
selection bias 
Source data 
All information in original records and certified copies of original records of 
clinical findings, observations, or other activities in a clinical study 
necessary for the reconstruction and evaluation of the study. Source data 
are contained in source documents (original records or certified copies). 
Standard of Care 
Medicine(s) for a specific indication, or a component of the standard care 
for a particular medical indication, based on national and/or international 
consensus; there is no regulatory significance to this term. 
Products/regimens considered standard of care may differ country to 
country, depending on consensus in individual countries 
Study intervention 
Term used throughout the clinical study to cover all types of investigational 
and non-investigational products, including medical devices and vaccines, 
intended to be administered to the study participants during the study 
conduct. Procedures conducted to manage participants or to collect data 
are excluded from the usage of this term. 
Study monitor 
An individual assigned by the sponsor and responsible for ensuring proper 
conduct of clinical studies at 1 or more investigational sites 
SUSAR 
In a clinical trial, a serious adverse reaction that is considered unexpected, 
i.e., the nature or severity of which is not consistent with the reference 
safety information (e.g., IB for an unapproved IMP). All ADRs that are both 
serious and unexpected are subject to expedited reporting. 

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10.21. 
Appendix 21: Protocol Amendment History 
The Protocol Amendment Summary of Changes Table for the current amendment is 
located directly before the Table of Contents. 
Summary of Previous Amendments 
Amendment 02 (19-Dec-2022) 
This amendment is considered to be substantial based on the criteria set forth in 
Article 10(a) of Directive 2001/20/EC of the European Parliament and the Council of the 
European Union. 
Overall Rationale for the Amendment: Amendment 02 is a global protocol amendment 
to align with program-level updates, removing the assessments of clinical responses by 
proprietary algorithm and only to be evaluated by the investigator as defined by 2016 
International Myeloma Working Group (IMWG) response criteria [Kumar, 2016]. Other 
program-level updates include removal of all minimal residual disease (MRD), total 
plasma monoclonal antibody and cfDNA assessments, and end of treatment collection of 
pharmacokinetic, anti-drug antibody, and serum B-Cell maturation antigen (sBCMA) 
samples to reduce participant burden. In addition, distinct definitions for the end of data 
collection for the final clinical study report and the end of study timepoints, including 
implementation of the PACT period in the study have been included. Risk assessment 
and alignment with updated risks in belantamab mafodotin Investigator’s Brochure v10 
has been amended in the protocol. 
Study-level changes that have been incorporated to include the addition of a defined 
evaluable population for the planned interim analysis, including an update to the interim 
analysis definition. To allow flexibility for participants with at least 3 prior lines to enroll 
in the study, the amended protocol removes the 20% limit for participants who have 
received 3 prior lines of therapy. Safety terminology has been updated, with ‘corneal 
events’ replacing ‘ocular AEs’ for the primary and secondary endpoints based on the 
keratopathy visual acuity (KVA) scale.  
Furthermore, additional clarifications have also been provided. A description and 
rationale for all changes is provided in the table that follows. 

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Section # and Name 
Description of Change 
Brief Rationale 
Section 1.1 Protocol Synopsis;  
Section 1.3 Schedule of 
Activities  
Section 3 Objectives and 
Endpoints and Estimands; 
Section 4.1 Overall Design; 
Section 4.2 Scientific Rationale 
for Study Design; 
Section 4.3 Justification for 
Selected Doses and Schedules 
Section 4.4 Rationale for the 
Investigation of Symptom-based 
Dose Modifications (Arm E) 
Section 6.5.1 Dose Modification 
for Corneal Events (Arms A to D) 
Section 9.2.1 Sample Size 
Assumptions: Primary Endpoint 
Section 9.4.1 Dosing based on 
Baseline Disease Characteristics 
– Virtual Treatment Arm 
Section 9.4.3 Safety Analyses 
Update of primary and 
secondary endpoints to specify 
terminology with ‘corneal events’ 
replacing ‘ocular AEs’. 
Alignment with program-level 
updates 
Section 1.1 Protocol Synopsis; 
Section 3 Objectives and 
Endpoints and Estimands; 
Section 8.4.1 Blood Sample 
Collection for Pharmacokinetics 
Section 8.4.2 Pharmacokinetic 
Sample Analysis 
Section 8.8 Immunogenicity 
Assessments 
Removed the assessment of 
total plasma monoclonal 
antibody concentration. 
The immunogenicity assay no 
longer requires total monoclonal 
antibody concentration values for 
interpretation. 
Section 1.1 Protocol Synopsis; 
Section 6.3 Measures to 
Minimize Bias: Randomization 
Removed enrollment target of 
having 20% of participants who 
have received 3 prior lines of 
therapy 
To allow flexibility for participants 
with at least 3 prior lines to enroll 
in the study  
Section 1.1 Synopsis 
Section 9.3.1 Analysis 
Populations 
Section 9.5 Interim Analysis 
Section 9.5.1 Independent Data 
Monitoring Committee 
Section 10.10.5 Committees 
Structure 
 
 
Clarification provided related to 
the Evaluable Population for 
planned interim analyses to 
occur after 15 participants each 
in Arms A to D have received 
2 doses of study treatment with 
1 disease assessment following 
the second dose, or confirmed 
progressive disease (PD) per 
IMWG [Kumar, 2016], or death.  
Clarification for data analyses 
including update for the interim 
analysis definition 

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Section # and Name 
Description of Change 
Brief Rationale 
Section 1.1 Synopsis 
Section 4.1 Overall Design 
Additional content to the overall 
study has been added which 
includes post analysis continued 
treatment (PACT) 
implementation and End of Study 
definition. Included distinct 
definitions for end of data 
collection timepoint for the final 
clinical study report (CSR) and 
End of Study timepoint.  
Clarification on End of Study and 
PACT definitions.  
 
Section 1.1 Synopsis 
Section 2.1 Study Rationale 
Section 2.3.2 Benefit 
Assessment  
Section 3 Objectives and 
Endpoints 
Section 4.1 Overall Design 
Section 4.3 Justification for 
Selected Doses and Schedules 
Section 9.2.2 Safety Stopping 
Rule for Arm E 
Removal of regulatory approval 
of belantamab mafodotin 
Alignment with program-level 
updates 
Section 1.3 Schedule of 
Activities 
Section 7.1 Discontinuation of 
Study Treatment 
Clarification that treatment 
discontinuation should be 
undertaken after confirmation of 
PD per IMWG criteria. 
Clarification for study conduct 
Section 1.3 Schedule of 
Activities 
Clarify confirmation of PD as per 
IMWG criteria prior to initiating a 
new anti-myeloma therapy. 
Clarification for study conduct 
Section 1.3 Schedule of 
Activities 
Clarification that information 
related to subsequent 
anti-myeloma therapies should 
be collected at any time after end 
of treatment visit. 
Clarification for study conduct 
Section 1.3 Schedule of 
Activities 
Section 10.13 Appendix 13 
Clinical Laboratory Tests  
Clarification that laboratory tests 
should be completed and 
reviewed 72 hours prior to 
dosing. 
Clarification for study conduct 
Section 1.3 Schedule of 
Activities 
Section 10.13 Appendix 13 
Clinical Laboratory Tests 
Clarification that ACR urine 
sample must be collected at 
screening. 
Clarification for study conduct 
Section 1.3 Schedule of 
Activities 
Section 8.1 Efficacy 
Assessments 
Clarification that PD must be 
confirmed by 2 central laboratory 
assessments. 
Clarification for study conduct 
Section 1.3 Schedule of 
Activities 
Clarification that serum/urine 
immunofixation will be performed 
each time that M-protein is not 
quantifiable by SPEP (0g/dL) or 
UPEP (0mg/24hr).  
Clarification for study conduct 

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Section # and Name 
Description of Change 
Brief Rationale 
Section 1.3 Schedule of 
Activities 
Sampling time windows for PK, 
sBCMA, and ADA assessments 
have been added to Table 4 
Clarification for study conduct 
Section 1.3 Schedule of 
Activities 
Section 8 Study Assessments 
and Procedures 
Section 8.2.5 Ocular 
Examinations 
Clarification on timing of ocular 
examinations when participant is 
not receiving a dose of study 
treatment. 
Clarification for study conduct 
Section 1.3 Schedule of 
Activities 
Revised to remove the EOT PK, 
ADA, and sBCMA.  
Alignment with program-level 
updates  
Section 1.3 Schedule of 
Activities  
Section 3 Objectives and 
Endpoints 
Section 8.1 Efficacy Assessment 
Section 8.1.2 Minimal Residual 
Disease Assessment 
Section 10.13 Appendix 13 
Clinical Laboratory Tests 
Revised to remove samples, 
exploratory endpoint and 
assessments related to MRD 
Alignment with program-level 
updates  
Section 1.3 Schedule of 
Activities  
Section 8.6 
Biomarkers/Translational 
Research 
Section 8.6.3 Circulating Plasma 
Cell-Free DNA Analysis 
Section 10.13 Appendix 13 
Clinical Laboratory Tests 
Revised to remove samples and 
analyses related to cfDNA 
Collection no longer required due 
to limited interoperability of 
cfDNA data and to reduce 
participant burden 
Section 1.3 Schedule of 
Activities;  
Section 5.1 Inclusion Criteria 
Section 5.2 Exclusion Criteria 
Section 6.8.2 Prohibited 
Medications and Non-drug 
therapies 
Section 7.1 Discontinuation of 
Study Treatment 
Section 8.2.5 Ocular 
Examinations 
Section 8.3.1 Time Period and 
Frequency for Collecting 
Adverse Event and Serious 
Adverse Event Information  
Section 10.18 Appendix 18: 
Progression-Free Survival Event 
and Censoring Rules 
Updated language to refer to 
anti-cancer therapy and/or 
anti-MM therapy as 
anti-myeloma therapy.  
Alignment with program-level 
updates 
Section 2.3.1 Risk Assessment 
Update to risk assessment and 
alignment with updated risks in 
belantamab mafodotin 
Investigator’s Brochure v10. 
Alignment with program-level 
updates 

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Section # and Name 
Description of Change 
Brief Rationale 
Section 4.6 End of Study 
Definition 
New paragraph added to align 
with PACT implementation. 
Included distinct definitions for 
end of data collection timepoint 
for the final CSR and End of 
Study timepoint. 
Clarification on End of Study and 
PACT definitions.  
Section 5.1 Inclusion Criteria 
(Criterion 3) 
Added definition of failed 
myeloma therapy 
Clarification for study conduct 
Section 5.2 Exclusion Criteria 
(Criterion 20) 
Added clarification that use of 
monoclonal antibodies for 
serious conditions are permitted 
after consultation with the 
Medical Director. 
Clarification for study conduct 
Section 6.1.1 Belantamab 
Mafodotin 
Window of intravenous 
administration has been 
broadened to 30-60 minutes. 
Update for study conduct 
Section 6.1.1 Belantamab 
Mafodotin 
Clarification on calculation of 
belantamab mafodotin dosage 
based on body weight. 
Clarification for study conduct 
Section 6.5 Dose Modification 
(Dose Reductions and Dose 
Delays) 
Clarification of conditions and 
timing of treatments related to 
dose delay. 
Clarification for study conduct 
Section 6.5.3 Dose Modification 
for Treatment-related Non-ocular 
Adverse Events (All Arms) 
Dose modification guidelines for 
belantamab mafodotin updated 
to align with NCI-CTCAE 
guidelines. 
Alignment with program-level 
updates  
Section 6.6 Continued Access to 
Study Treatment after the End of 
the Study  
Updated the title and language of 
the section to align with PACT 
implementation. 
Clarification on End of Study and 
PACT definitions.  
Section 6.6.1 Continued Access 
to Study Treatment after the 
Final Data Cutoff prior to End of 
the Study 
Section 8.3.1 Time Period and 
Frequency for Collecting AE and 
SAE Information 
Updated language to align with 
PACT implementation. 
Clarification on End of Study and 
PACT definitions.  
Section 6.8 Concomitant 
Therapy 
Guidance added for study 
participants who may be 
diagnosed with unrelated 
malignancy and concomitant 
therapies. 
To define the allowance of local 
therapy for unrelated 
malignancies 
Section 6.8.2 Prohibited 
Medications and Non-Drug 
Therapies 
Clarification added to define 
scope of myeloma therapy. 
Clarification for study conduct 

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Section # and Name 
Description of Change 
Brief Rationale 
Section 8.1.1 Response 
Evaluation 
Section 9.4.4 Efficacy Analyses 
Section 10.18 Progression-Free 
Survival Event and Censoring 
Clinical response assessments 
for relapsed or refractory multiple 
myeloma (RRMM) will only be 
evaluated by the investigator as 
defined by 2016 IMWG response 
criteria [Kumar, 2016], as data 
permits, removing the 
assessment by proprietary 
algorithm. 
Updated as per regulatory 
agency feedback on other 
DREAMM studies 
Section 8.2.2 Vital Signs 
Removed requirement for semi-
supine position while obtaining 
vital sign measurements 
Clarification for study conduct 
Section 8.2.5 Ocular 
Examinations 
Clarification on timing of ocular 
examinations when participant 
has reached end of treatment. 
Clarification for study conduct 
Section 8.3.5 Pregnancy 
Updated language to indicate the 
investigator will follow up 6 to 8 
weeks after delivery. 
To align with updated neonate 
follow-up in current informed 
consent form 
Section 9.3.1 Analysis 
Populations 
Clarification added on the 
definition of the PK evaluable 
population 
Clarification for study analysis 
Section 9.4.5.1 Pharmacokinetic 
Data Analysis 
Clarification provided related to 
the planned pharmacokinetic 
analyses.  
Clarification for study conduct 
Section 10.7 Appendix 7: 
Country-Specific Requirements 
Limit enrollment to only 
participants who have failed at 
least 4 prior lines of 
anti-myeloma therapies (France-
specific). 
Regulatory agency requirement 
(France) incorporated into the 
global protocol amendment from 
France-specific protocol 
amendment.  
Section 10.10.7 Appendix 10 
Data Quality Assurance 
Update to indicate that quality 
tolerance limits are pre-defined 
in the Quality tolerance limits 
(QTL) plan. 
Clarification for data quality 
management 
Section 10.10.11  
Third Parties and Subcontractors 
Listing of third parties and 
subcontractors supporting this 
study. 
Added for clinical trial 
transparency 
Section 10.13 Appendix 13 
Clinical Laboratory Tests 
Removed requirement for 
reticulocyte assessment as a 
part of clinical laboratory testing. 
Additional updates related to 
CO2 and PK assessments. 
To allow for greater flexibility for 
sites and clarification for study 
conduct 
Section 10.18 Appendix 18: 
Progression-Free Survival Event 
and Censoring Rules 
Updates to progression-free 
survival censoring rule, and 
definitions of adequate 
assessment and loss-to-follow-
up window 
Alignment with program-level 
updates 
Section 10.21 Appendix 21 
Abbreviations and Trademarks 
Updated to include PACT  
Standard document practice 
Throughout the document 
Minor editorial and document 
formatting changes 
Minor, therefore have not been 
summarized 

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Abbreviations: BCVA=best corrected visual acuity; CR=Complete response; DoR=Duration of Response; 
IMWG=International Myeloma Working Group; KVA=keratopathy visual acuity; logMAR= logarithm of the minimum 
angle of resolution; MRD=minimal residual disease; OS=overall survival; OSDI=Ocular Surface Disease Index; 
PACT=post analysis continued treatment; PD=progressive disease; PFS=progression-free survival; PR=partial 
response; PRO-CTCAE=Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events; 
QTL=quality tolerance limit; SPEP=serum protein electrophoresis; sCR=stringent Complete Response ; UPEP=urine 
protein electrophoresis; VGPR=very good partial response. 
 
Amendment 01 (21-Jan-2022) 
This amendment is considered to be substantial based on the criteria set forth in 
Article 10(a) of Directive 2001/20/EC of the European Parliament and the Council of the 
European Union. 
Overall Rationale for the Amendment: Amendment 01 is a global protocol amendment 
to address health authority feedback. Additional clarifications have also been provided. A 
description and rationale for all changes is provided in the table that follows. 
Section # and Name 
Description of Change 
Brief Rationale 
Document headers, Title Page, 
Sponsor Signatory page, 
Protocol Amendment Summary 
of Changes section (new) 
Document headers, Title Page, 
and Sponsor Signatory page 
were updated according to the 
Sponsor’s template; Protocol 
Amendment Summary of 
Changes section was added 
Editorial changes to align with 
the Sponsor’s standard protocol 
template and ways of working 
1.1. Synopsis (Objectives and 
Endpoints) 
 
3. Objectives and Endpoints and 
Estimands 
 
8.1 Efficacy Assessments 
 
9.4.4 Efficacy Analyses 
(Table 17) 
Updated the definition of DoR to 
include death due to any cause 
 
 
Health authority request that 
death due to any cause should 
be included in the DoR definition 
1.1 Synopsis (Overall Design) 
 
4.1 Overall Design 
 
4.6 End of Study Definition/Study 
Completion 
 
9.2.1 Sample Size Assumptions: 
Primary Endpoint 
Amended the timing of when the 
primary analysis will be 
performed 
Health authority recommendation 
that all subjects have a minimum 
of 9-12 months follow-up from 
the onset of first response to 
allow for an adequate 
assessment of durability of 
response and safety 

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Section # and Name 
Description of Change 
Brief Rationale 
1.1. Synopsis (Study Treatment 
Groups and Duration) 
5.1. Inclusion Criteria 
(criterion 4d) 
Removed the measurable 
disease inclusion criterion for 
participants with only 
extramedullary disease 
(non-irradiated plasmacytoma 
with 1 measurable lesion that 
has a single diameter of 2 cm) 
and corresponding enrollment 
cap (5%) of these participants 
Health authority request as this 
is not in the IMWG definition of 
measurable disease 
5.2 Exclusion Criteria 
(criterion 21) 
Added hypersensitivity or 
idiosyncratic reaction to 
belantamab mafodotin or any 
study treatment components 
Health authority request that 
these participants are excluded 
from the study 
5.2 Exclusion Criteria 
(criterion 24) 
Changed units of measure of 
hemoglobin from 109/L to g/dL. 
Error correction 
1.3 Schedule of Activities (OS 
Follow-Up, footnote 9, and 
footnote 42) 
6.5.1. Dose Modification for 
Ocular Adverse Events (Arms A 
to D)/ Table 8 KVA Scale and 
Dose Modification Guidelines for 
Corneal Toxicities for 
Belantamab Mafodotin 
Treatment for Arms A to D (new 
footnote a) 
6.8.1. Ocular Supportive Care: 
Guidelines and Prophylactic 
Measures 
7.1.2. Corneal Event Stopping 
Criteria 
8.2.5. Ocular Examinations 
9.2.2. Safety Stopping Rule for 
Arm E/Table 14 Safety Stopping 
Rule for Arm E 
Removed “treatment-related” 
qualifier when referencing ocular 
toxicity/corneal findings and 
provided a list of exceptions to 
ocular toxicities/corneal findings 
considered not to be related to 
belantamab mafodotin  
Health authority request to 
provide clarity around ocular 
toxicity/corneal findings not being 
monitored in participants as it is 
expected most events may be 
related to study treatment 

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Section # and Name 
Description of Change 
Brief Rationale 
6.5.1. Dose Modification for 
Ocular Adverse Events (Arms A 
to D)/Table 8 KVA Scale and 
Dose Modification Guidelines for 
Corneal Toxicities for 
Belantamab Mafodotin 
Treatment for Arms A to D 
6.5.2. Dose Modifications Based 
on Ocular Symptoms, Visual 
Acuity Assessments, and 
Corneal Findings 
(Arm E)/Table 9 Dose 
Modification Guidelines for 
Belantamab Mafodotin 
Treatment for Arm E based on 
OSDI, Visual Acuity, and Corneal 
Findings 
Table 8 only: Corrected Grade 2 
change in Snellen-Equivalent 
BCVA to, “…and is equal to or 
better than 1.0 logMAR 
(20/200)”; Corrected Grade 3 
change in Snellen-Equivalent 
BCVA to, “…and is equal to or 
better than 1.0 logMAR 
(20/200)”; Corrected Grade 4 
change in Snellen-Equivalent 
BCVA to, “Visual acuity is worse 
than 1.0 logMAR (20/200).” 
Table 8 only: Added a new 
footnote (e) to specify that 
Grade 4 “Corneal ulcer” includes 
other corneal epithelial defects 
such as corneal erosions. 
Table 8 and Table 9: Updated 
dose modification guidelines to 
advise permanent 
discontinuation of belantamab 
mafodotin in participants 
receiving the lowest dose and 
who experience a Grade 4 event 
according to the KVA scale. 
However, investigators may 
submit a request for treatment 
continuation to be reviewed by 
the sponsor. 
Error correction to align with the 
belantamab mafodotin label 
Program update as these severe 
corneal defects have been 
observed in other DREAMM 
studies and to ensure participant 
safety. 
Health authority request that 
these participants be 
permanently discontinued from 
study treatment 

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Section # and Name 
Description of Change 
Brief Rationale 
6.5.2. Dose Modifications Based 
on Ocular Symptoms, Visual 
Acuity Assessments, and 
Corneal Findings 
(Arm E)/Table 9 Dose 
Modification Guidelines for 
Belantamab Mafodotin 
Treatment for Arm E based on 
OSDI, Visual Acuity, and Corneal 
Findings 
Throughout (including Figure 1 
DREAMM-14 Study Schema) 
Updated visual acuity criteria 
from 0.3 to 0.1 logMAR and 
corneal findings criteria to be 
based on Grades 2 through 4 
according to the KVA scale. 
Per the above change, updated 
the protocol wording throughout 
that Arm E dose modifications 
that are based on ocular 
symptoms (patient-reported 
symptoms using the OSDI), 
visual acuity assessments 
(Snellen chart or equivalent), 
and corneal findings (KVA 
scale). 
Health authority request to revise 
the dose modification guidelines 
for Arm E to hold belantamab 
mafodotin for Grade 2 events 
according to the KVA scale 
7.1 Discontinuation of Study 
Treatment 
Updated the protocol wording to 
clarify that study treatment 
discontinuation is mandatory in 
case of PD, unacceptable 
toxicity, pregnancy or in case the 
participant has met any of the 
protocol-defined safety stopping 
criteria. 
Update per health authority 
request 
8.1.2. Minimal Residual Disease 
Assessment 
Clarified that MRD assessments 
will be performed using the 
clonoSEQ assay and that MRD 
negativity will be assessed using 
a 10-5 sensitivity threshold in 
participants achieving a 
response of CR or better. The 
MRD negativity rate in 
participants achieving a 
response of VGPR or better 
will be assessed as an 
additional sensitivity analysis. 
Update per health authority 
request 
8.9.1.1. Patient-Reported 
Outcomes version of the 
Common Terminology Criteria 
for Adverse Events (PRO-
CTCAE) 
Specified what items of the 
PRO-CTCAE will be assessed 
Clarification of the exact 
PRO-CTCAE items that will be 
administered in the study per 
health authority request 

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Section # and Name 
Description of Change 
Brief Rationale 
9.2.1 Sample Size Assumptions: 
Primary Endpoint/Table 13 Study 
Safety Operating Characteristics 
Changed acceptance criteria and 
introduced an additional criterion 
based on lower 95% CI of the 
estimates on difference in 
Grade 2 corneal event rates 
between test and control arms 
Update per health authority 
request 
9.4. Key Elements of Statistical 
Analysis Plan 
Removed redundant information 
regarding statistical comparison 
of the treatment arms to the 
control arm 
Information already presented in 
Section 9.2.1. Sample Size 
Assumptions: Primary Endpoint 
9.4.4. Efficacy Analyses/ 
Table 17 Statistical Analytical 
Methods: Efficacy 
Updated the statistical analysis 
methods to correctly describe 
approach for the secondary 
endpoints of OS and PFS 
Correction/clarification per health 
authority request 
10.4. Appendix 4 Decentralized 
and Remote Assessment 
Approaches (and corresponding 
wording referencing Section 10.4 
in Section 1.3. Schedule of 
Activities (SoA)) 
Removed home healthcare and 
telemedicine measures. 
Clarified that eye examinations 
not performed centrally are to be 
conducted at only a specified 
alternative eye care specialist 
clinic, not in the participant’s 
home. These visits are 
considered decentralized 
assessments and not home 
healthcare, telemedicine, or 
remote eye examinations. 
Removed home healthcare and 
telemedicine measures as they 
are not considered appropriate 
for the study at this time. 
Clarification to study conduct if 
measures for decentralized eye 
examinations are followed per 
health authority request 
10.18. Appendix 18: 
Progression-Free Survival Event 
and Censoring Rules 
In the “Date of Event” column of 
the “Death or PD after missing 
2 or more scheduled 
assessments” row, corrected, 
“…since disease assessment is 
every 4 weeks, a window of 
70 days (6 weeks + 3-day 
window)” to “…since disease 
assessment is every 3 weeks, a 
window of 49 days (6 weeks + 
7-day window)” and corrected, “If 
the time difference between 
PD/death…is more than 49 
days,” 
Error correction and alignment 
with other DREAMM studies 
Abbreviations: BCVA=best corrected visual acuity; CR=Complete response; DoR=Duration of Response; 
IMWG=International Myeloma Working Group; KVA=keratopathy visual acuity; logMAR= logarithm of the 
minimum angle of resolution; MRD=minimal residual disease; OS=overall survival; OSDI=Ocular Surface Disease 
Index; PD=progressive disease; PFS=progression-free survival; PR=partial response; PRO-CTCAE= 
Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events; VGPR=very good 
partial response. 
 

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10.22. 
Appendix 22: French-Specific Requirements 
This appendix includes all applicable requirements of French Public Health Code / 
specific local GSK requirements and identifies, item per item, the mandatory 
modifications or additional information to the study protocol. 
 
1. Concerning the « SELECTION OF STUDY POPULATION AND 
WITHDRAWAL CRITERIA»  
 
A subject will be eligible for inclusion in this study if he /she is either affiliated to or 
beneficiary of a social security category (French Public Health Code L.1124-1).  
It is the investigator’s responsibility to ensure and to document (in the source document - 
subject notes) that the subject is affiliated to or beneficiary of a social security category. 
 
 
2. Concerning the “STUDY GOVERNANCE CONSIDERATIONS” 
• In section “Regulatory and Ethical Considerations, including the Informed 
Consent Process” of study protocol 
 Concerning the process for informing the subject and/or his/her legally 
authorized representative, the following text is added:  
French Patient Informed Consent is a document which summarizes the main features of 
the study and allows collection of the subject and/or his/her legally authorized 
representative written consent. It also contains a reference to the single scientific and 
ethical regulatory authorisation. 
 
 Concerning the process for obtaining subject informed consent: 
 
➢ When a research involving human being is carried out on a minor / on an 
adult in the care of a “tutelle” guardian, consent is given by their legal 
representative. 
 
➢ When research involving human being is carried out on an adult in the 
care of a "curatelle" guardian, consent is given by the subject assisted by 
his guardian. 
 
When research involving human being is considered for an adult incapable of expressing 
her/his consent and not under a legal protection order, consent is given by a person of 
trust as defined in article L. 1111-6 and, failing this, by the family, or a person who 
maintains close and stable links with the subject.  
 
 Concerning the management of the Patient Informed Consent Forms, the 
following text is added: 
 
French Patient Informed Consent Form is in duplicate (triplicate for minor subject). 
The first page of the Patient Informed Consent Form is given to the investigator. The copy 
is kept by the patient or legally authorized representative. 
 
 

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•  NOTIFICATION TO THE HOSPITAL DIRECTOR 
In accordance with Article R.1123-69 of the French Public Health Code, the Hospital 
Director is informed of the commitment to the trial in her/his establishment. The Hospital 
Director is supplied with the protocol and any information needed for the financial 
disposition, the name of the investigator(s), the number of sites involved in his 
establishment and the estimated time schedule of the trial. 
 
• INFORMATION TO THE HOSPITAL PHARMACIST 
In accordance with Article R.1123-70 of the French Public Health Code, the Hospital 
Pharmacist is informed of the commitment to the trial in her/his establishment. The 
Pharmacist is supplied with a copy of the protocol (which allows her/him to dispense the 
drug(s) of the trial according to the trial methodology), all information concerning the 
product(s) of the trial (e.g. included in the IB), the name of the investigator(s), the number 
of sites involved in her/his establishment and the estimated time schedule of the trial. 
 
• Ethnic Origin 
In accordance with the data privacy regulation, the ethnic origin, as any personal data, can 
only be collected if the collection of this data is strictly necessary and relevant for the 
purpose of the study. 
 
• TESTING OF BIOLOGICAL SAMPLES 
In accordance with the French Public Health Code – article L1211-2, a biological sample 
without identified purpose at the time of the sample and subject’s preliminary information 
is not authorized. 
 
3. Concerning the “ DATA MANAGEMENT ” the following text is added: 
Within the framework of this clinical trial, data regarding the identity of the investigators 
and/or co-investigators and/or the pharmacists if applicable, involved in this clinical trial, 
and data regarding the subjects recruited in this clinical trial (subject number, treatment 
number, subjects status with respect to the clinical trial, dates of visit, medical data) will 
be collected and computerized in GSK data bases by GSK or on its behalf, for reasons of 
follow up, clinical trial management and using the results of said clinical trial. According 
to the data privacy regulation, each of these people aforesaid has a right of access, 
correction and opposition on their own data through GSK (Clinical Operations 
Department). 
 
4. Concerning Data Privacy 
In accordance with the applicable data privacy regulation, personal data are processed in a 
manner that ensures appropriate security, including protection against unauthorized or 
unlawful processing and against accidental loss, destruction or damage, using appropriate 
technical or organizational measures. The processing is whether deemed to be compliant 
with one of the methodology of reference (MR-001) or has been the subject of a request 
for authorization to the CNIL. The Investigator has, regarding the processing data related 
to her/him, a right of access, of rectification, erasure and of opposition with GSK in 
accordance with the legal provisions. 
 

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5. Investigational Product Accountability, Reconciliation, and Destruction 
In specific situations where institutional practices dictate that the site disposes of and/or 
destroys IP prior to allowing the “monitor” to verify and document IP accountability, the 
following applies: 
 
“During the conduct of the Study, Investigational Product (IP) will be destroyed by the 
Institution prior to a GSK “monitor” conducting final investigational product 
accountability. Institution agrees that such destruction will comply with Institution’s 
investigational product accountability procedures and will provide GSK with 
investigational product accountability logs and supporting documentation to verify 
adherence to ‘Bonnes Pratiques Cliniques’ (decision dated on the 24th of November 
2006). 
 

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11. 
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Signature Page for  209628 TMF-19107833 v2.0
Signature Page for TMF-19107833 v2.0
Reason for signing: Approved
Name:
Role: Approver
Date of signature: 25-Jun-2024 13:24:19 GMT+0000
PPD