A Phase II, Single-blind, Randomized, Placebo-controlled Trial to Study the Efficacy and Safety of Anti-von Willebrand Factor Nanobody Administered as Adjunctive Treatment to Patients With Acquired Thrombotic Thrombocytopenic Purpura
Phase: PHASE2
Conditions: Acquired Thrombotic Thrombocytopenic Purpura
Sponsor: Ablynx, a Sanofi company

Ablynx NV 
Clinical Study Protocol 
Study ALX-0681-2.1/10 
June 24, 2013 
CONFIDENTIAL  
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CLINICAL STUDY PROTOCOL 
 
A PHASE II, SINGLE-BLIND, RANDOMISED, PLACEBO-CONTROLLED TRIAL  
TO STUDY THE EFFICACY AND SAFETY OF  
ANTI-VON WILLEBRAND FACTOR NANOBODY  
ADMINISTERED AS ADJUNCTIVE TREATMENT TO PATIENTS WITH  
ACQUIRED THROMBOTIC THROMBOCYTOPENIC PURPURA 
 
CONFIDENTIAL 
 
CRO code: AYX081PR-AL0081 
Sponsor code: ALX-0681-2.1/10 
EudraCT number: 2010-019375-30 
 
Investigational product:  
ALX-0081, anti-von Willebrand factor Nanobody  
INN: caplacizumab 
Clinical Phase:  
 
Phase II study 
Indication to be studied:  
Acquired thrombotic thrombocytopenic purpura 
 
Sponsor 
 
 
Ablynx NV, Technologiepark 21, B-9052 Zwijnaarde, Belgium 
Sponsor’s Contact 
 
  
 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
Coordinating Investigator 
 
 
 
 
 
  
  
 
 
 
 
 
 
 
 
 
 
 
  
 
 
Version  
 
 
Final version 12.0 
 
Date 
 
 
 
24 June 2013  
 
 
 
 
 
 
 
This study will be performed in compliance with the principles of Good Clinical Practice (GCP). 
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Clinical Study Protocol 
Study ALX-0681-2.1/10 
June 24, 2013 
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Investigator Signature Page 
 
I have read the protocol of study ALX-0681-2.1/10, version 12.0. I understand the contents 
and intend to comply fully with all requirements and the applicable current local and 
international regulations and guidelines. No changes will be made without formal 
authorisation by Ablynx NV in the form of a protocol amendment. 
 
 
 
 
Investigator Signature: ______________________________ 
___________________ 
Investigator Name (block letters): _________________________ 
Date 
Institution: _________________________________________ 
 
 
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June 24, 2013 
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RESPONSIBILITIES AND CONTACT INFORMATION 
 
Sponsor's Study Manager 
 
Ablynx NV 
Technologiepark 21 
B-9052 Zwijnaarde 
Belgium 
Phone: +32 (0)9 262 00 00 
Fax: 
+32 (0)9 262 00 02 
 
CRO Project Management 
 
  
  
  
  
 
 
 
  
 
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SERIOUS ADVERSE EVENT CONTACT INFORMATION 
 
In the event of a serious adverse event, the Investigator will send a faxed report within 
24 hours of notification to: 
 
CRO 
 
 
 
 
 
 
 
  
 
 
 
 
MEDICAL EMERGENCIES 
In the event of a medical emergency the Medical Monitor (CRO) can be contacted by 
investigative staff at: 
 
CRO 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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June 24, 2013 
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TABLE OF CONTENTS 
SIGNATURES ........................................................................................................................ 2 
RESPONSIBILITIES AND CONTACT INFORMATION ......................................................... 4 
SERIOUS ADVERSE EVENT CONTACT INFORMATION .................................................... 5 
MEDICAL EMERGENCIES .................................................................................................... 5 
TABLE OF CONTENTS ......................................................................................................... 6 
LIST OF ABBREVIATIONS ................................................................................................. 10 
LIST OF TABLES ................................................................................................................ 13 
LIST OF FIGURES ............................................................................................................... 14 
LIST OF APPENDICES ....................................................................................................... 15 
1. 
STUDY SYNOPSIS ....................................................................................................... 16 
2. 
BACKGROUND INFORMATION .................................................................................. 26 
2.1 
Introduction ........................................................................................................................ 26 
2.1.1 
Role of vWF in Platelet Aggregation ....................................................................... 26 
2.1.2 
Role of vWF and vWF Processing in Pathophysiology of TTP .............................. 26 
2.1.3 
Role of vWF in Other Pathologies .......................................................................... 27 
2.2 
ALX-0081, anti-vWF Nanobody ........................................................................................ 27 
2.3 
Nonclinical Study Data ...................................................................................................... 28 
2.3.1 
Pharmacology ......................................................................................................... 28 
2.3.2 
Pharmacokinetics ................................................................................................... 30 
2.3.3 
Toxicology ............................................................................................................... 31 
2.4 
Clinical Experience ............................................................................................................ 32 
2.4.1 
Clinical Trials Supporting ACS Indication ............................................................... 35 
2.4.2 
Clinical Trial Supporting TTP Indication: Phase I Study in Healthy Volunteers ..... 37 
2.5 
Safety/Risk Profile ............................................................................................................. 40 
2.5.1 
Potential Risks ........................................................................................................ 40 
2.5.2 
Potential Benefits .................................................................................................... 43 
2.6 
Rationale for Dose Selection ............................................................................................ 47 
3. 
OBJECTIVES ................................................................................................................ 48 
4. 
TRIAL DESIGN ............................................................................................................. 49 
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4.1 
Study Endpoints ................................................................................................................ 49 
4.1.1 
Primary Endpoint .................................................................................................... 49 
4.1.2 
Secondary Endpoints .............................................................................................. 49 
4.1.3 
Tertiary Endpoints ................................................................................................... 50 
4.2 
Overall Study Design ........................................................................................................ 50 
4.3 
Overview of Treatment and Dosing Regimen for Study Drug ...................................... 52 
4.4 
Study Duration ................................................................................................................... 52 
4.5 
DSMB and Premature Termination of the Study ............................................................ 52 
4.5.1 
Data Safety Monitoring Board................................................................................. 52 
4.5.2 
Premature Termination of the Study ....................................................................... 53 
5. 
SELECTION AND WITHDRAWAL OF SUBJECTS ...................................................... 54 
5.1 
Inclusion Criteria ............................................................................................................... 54 
5.2 
Exclusion Criteria .............................................................................................................. 54 
5.3 
Participation in concurrent clinical trials ........................................................................ 55 
5.4 
Withdrawal of Subjects from Study ................................................................................. 55 
5.4.1 
Definitions ............................................................................................................... 55 
5.4.2 
Subject Discontinuation or Withdrawal ................................................................... 56 
5.4.3 
Procedure for Handling Withdrawals and Replacements ....................................... 57 
6. 
STUDY DRUGS ............................................................................................................ 58 
6.1 
Formulation, Packaging and Labelling ........................................................................... 58 
6.1.1 
Study Drug Formulation .......................................................................................... 58 
6.1.2 
Study Drug Packaging ............................................................................................ 58 
6.1.3 
Study Drug Labelling .............................................................................................. 59 
6.2 
Storage and Stability ......................................................................................................... 59 
6.3 
Study Drug Preparation and Administration .................................................................. 59 
6.4 
Return of Study Drug ........................................................................................................ 60 
6.5 
Drug Accountability .......................................................................................................... 61 
7. 
TREATMENT ................................................................................................................ 62 
7.1 
Treatments to be Administered ........................................................................................ 62 
7.2 
Treatment and Dosing Regimen for Study Drug ............................................................ 62 
7.3 
Dose modification due to treatment related AE – clinically relevant bleeding ........... 64 
7.4 
Prior / Concomitant Medication ....................................................................................... 65 
7.5 
Assignment to Treatment ................................................................................................. 66 
7.6 
Management of Overdose ................................................................................................. 66 
7.7 
Management of Hypersensitivity Reactions ................................................................... 67 
7.8 
Restrictions ........................................................................................................................ 67 
7.9 
Treatment Compliance ...................................................................................................... 67 
8. 
STUDY ASSESSMENTS AND PROCEDURES ............................................................ 68 
8.1 
Description of Study Days and Schedules of Assessments ........................................ 68 
8.1.1 
Screening and Baseline Measurements ................................................................. 72 
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8.1.2 
Treatment Phase .................................................................................................... 76 
8.1.3 
Follow-up ................................................................................................................ 84 
8.1.4 
Unscheduled Additional Visit .................................................................................. 90 
8.1.5 
Exacerbation and relapse visits .............................................................................. 91 
8.2 
Assessment of Efficacy .................................................................................................... 91 
8.2.1 
Clinical Outcome ..................................................................................................... 91 
8.2.1.1 
Outcomes of Special Interest ................................................................ 92 
8.2.2 
Pharmacodynamics ................................................................................................ 93 
8.2.3 
Laboratory Markers of Disease............................................................................... 94 
8.3 
Assessment of Safety ....................................................................................................... 94 
8.3.1 
Safety Laboratory Monitoring.................................................................................. 94 
8.3.2 
Physical Examination and Vital Signs .................................................................... 96 
8.3.3 
Bleeding Events ...................................................................................................... 97 
8.3.4 
Cardiovascular Monitoring ...................................................................................... 98 
8.3.5 
Glasgow Coma Score ............................................................................................. 98 
8.3.6 
Neurocognitive Battery ........................................................................................... 98 
8.3.6.1 
CNTB .................................................................................................... 99 
8.3.6.2 
Category Fluency Test ........................................................................ 100 
8.3.6.3 
Letter Fluency Test ............................................................................. 100 
8.3.7 
Adverse Events ..................................................................................................... 100 
8.3.8 
Immunogenicity ..................................................................................................... 101 
8.4 
Pharmacokinetic Assessment ........................................................................................ 101 
8.4.1 
Sampling ............................................................................................................... 101 
8.4.2 
Labelling and Shipping Procedures for PK Samples ............................................ 102 
8.4.3 
Analytical Assays .................................................................................................. 102 
8.4.4 
Pharmacokinetics ................................................................................................. 102 
9.
SAFETY DEFINITIONS AND REPORTING REQUIREMENTS ................................... 103 
9.1 
Adverse Events ................................................................................................................ 103 
9.1.1 
Definitions of Adverse Events ............................................................................... 103 
9.1.2 
Definition of Adverse Reaction (AR) ..................................................................... 104 
9.1.3 
Intensity of Adverse Events .................................................................................. 104 
9.1.4 
Classification according to CTCAE ....................................................................... 105 
9.1.5 
Relationship to Study Drug ................................................................................... 105 
9.1.6 
Reporting of Adverse Events ................................................................................ 106 
9.1.7 
Follow-up of Adverse Events ................................................................................ 106 
9.2 
Serious Adverse Events/Serious Adverse Reaction.................................................... 106 
9.2.1 
Definitions ............................................................................................................. 106 
9.2.1.1 
Serious Adverse Events/Serious Adverse Reaction (SAE/SAR) ....... 106 
9.2.1.2 
Hospitalisation and Prolongation of Existing Hospitalisation .............. 107 
9.2.1.3 
Serious Adverse Events Related to Study-mandated Procedures ..... 107 
9.2.1.4 
Suspected Unexpected Serious Adverse Reaction (SUSAR) ............ 108 
9.2.2 
Reporting of Serious Adverse Events ................................................................... 108 
9.2.2.1 
Before Study Drug Initiation ................................................................ 108 
9.2.2.2 
During Study Drug Administration ...................................................... 108 
9.2.2.3 
After Study Drug Discontinuation........................................................ 108 
9.2.2.4 
Reporting Procedures by the Investigator .......................................... 108 
9.2.3 
Follow-up of Serious Adverse Events ................................................................... 109 
9.2.4 
Reporting Procedures by the CRO on behalf of the Sponsor .............................. 109 
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10. STATISTICAL PROCEDURES ................................................................................... 110 
10.1 Study Populations ........................................................................................................... 110 
10.2 Statistical and Analytical Plan for Pharmacokinetic Evaluation ................................ 110 
10.3 Evaluation of Safety and Tolerability Parameters ........................................................ 111 
10.4 Determination of Sample Size ........................................................................................ 111 
10.5 Assessment of Primary Endpoint .................................................................................. 112 
10.6 Analysis of Efficacy Parameters and Secondary Endpoints ...................................... 112 
10.7 Analysis of Tertiary and Exploratory Endpoints .......................................................... 112 
11. ETHICAL ISSUES AND INSURANCE ........................................................................ 113 
11.1 Independent Ethics Committee ...................................................................................... 113 
11.2 Ethical Conduct of the Study ......................................................................................... 113 
11.3 Patient Information and Consent ................................................................................... 113 
11.4 Insurance/Liability ........................................................................................................... 114 
12. GENERAL 
REGULATIONS, 
AGREEMENTS 
AND 
ORGANISATIONAL
PROCEDURES ........................................................................................................... 115 
12.1 Legal Aspects/Declaration of Helsinki .......................................................................... 115 
12.2 Investigator’s Brochure .................................................................................................. 115 
12.3 Data Protection ................................................................................................................ 115 
12.4 Monitoring ........................................................................................................................ 115 
12.5 Audits and Inspections ................................................................................................... 116 
12.6 Storage of Study Records in the Investigator’s File .................................................... 116 
12.7 Costs ................................................................................................................................. 117 
12.8 Confidentiality .................................................................................................................. 117 
12.9 The Clinical Study’s Approval and General Obligation of Notification ...................... 117 
12.10 Final Report and Publication .......................................................................................... 117 
13. REFERENCES ............................................................................................................ 119
14. APPENDICES ............................................................................................................. 122 
14.1 Appendix 1: Declaration of Helsinki .............................................................................. 122 
14.2 Appendix 2: Common Terminology for Adverse Events v4.0 (CTCAE) ..................... 126 
14.3 Appendix 3: Elements of Informed Consent ................................................................. 126 
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LIST OF ABBREVIATIONS 
ACS 
Acute coronary syndrome 
ACT 
Activated clotting time 
ADA 
Anti-drug antibody 
ADAMTS13 
A disintegrin-like and metalloprotease with thrombospondin repeats 13 
AE 
Adverse event 
ALT 
Alanine transaminase 
AP 
Alkaline phosphatase 
aPTT 
Activated partial thromboplastin time 
AR 
Adverse (drug) reaction 
ASAP 
As soon as possible 
AST 
Aspartate transaminase 
AUC0-t 
Area under the plasma concentration vs. time curve up to time t 
AUC0-24 
Area under the plasma concentration vs. time curve up to 24 hour 
AUCextra 
Extrapolated AUC obtained from Ct/Lambda z 
AUCinf 
Area under the plasma concentration vs. time curve up to infinite 
AUC0-ι 
Area under the plasma concentration vs. time curve between dosing intervals 
BED 
Biologically effective dose 
BMI 
Body mass index 
BNP 
Brain natriuretic peptide or B-type natriuretic peptide 
BUN 
Blood urea nitrogen 
Ca 
Calcium 
Cl 
Chloride 
CL 
Clearance 
Cmax 
Maximum observed plasma concentration 
CNTB 
Computerised neuropsychological test battery 
CRF 
Case report form 
CRO 
Contract research organisation 
CRP 
C-reactive protein
CRT 
Choice reaction time
CSR 
Clinical study report
CTCAE 
Common terminology criteria for adverse events
CV 
Coefficient of variation
d 
Day
DAP 
Data analysis plan
DAT 
Direct antiglobulin test
DIC 
Disseminated intravascular coagulation
DSMB 
Data safety monitoring board
EC 
Ethics committee
ECG 
Electrocardiogram
ELISA 
Enzyme-linked immunosorbent assay
FVIII 
Coagulation factor VIII
g 
Gram
GCP 
Good clinical practice
GFR 
Glomerular filtration rate
GLP 
Good laboratory practice
GP 
Glycoprotein
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h 
Hour 
HBsAg 
Surface antigen of the hepatitis B virus 
HBV 
Hepatitis B virus 
hCG 
Human chorionic gonadotropin 
HCV 
Hepatitis C virus 
HIV 
Human immunodeficiency virus 
HUS 
Haemolytic-uremic syndrome 
i.a. 
Intra-arterial 
IB 
Investigator’s Brochure 
ICH 
International conference on harmonisation 
IEC 
Independent ethics committee 
i.m. 
Intramuscular 
INR 
International normalised ratio 
IRB 
Institutional review board 
ITP 
Immune thrombocytopenic purpura 
ITT 
Intention-to-treat 
IU 
International unit 
i.v. 
Intravenous(ly) 
λz 
Elimination rate constant 
K 
Potassium 
kg 
Kilogram 
LDH 
Lactate dehydrogenase 
LLN 
Lower limit of normal 
LMWH 
Low molecular weight heparin 
m 
Month 
MD 
Multiple dose 
MCH 
Mean corpuscular haemoglobin 
MCV 
Mean corpuscular volume 
MCHC 
Mean corpuscular haemoglobin concentration 
MedDRA 
Medical Dictionary for Regulatory Activities 
Mg 
Magnesium 
mg 
Milligram 
min 
Minute 
mL 
Millilitre 
µL 
Microlitre 
mm 
Millimetre 
MRT 
Mean residence time 
MTD 
Maximum tolerated dose 
Na 
Sodium 
NA 
Not applicable 
NOAEL 
No observed adverse effect level 
NSE 
Neuron specific enolase 
NT-proBNP 
N-terminal pro B-type natriuretic peptide or N-terminal pro brain natriuretic peptide 
OLE 
Open label extension 
PCI 
Percutaneous coronary intervention 
PD 
Pharmacodynamics 
PE 
Plasma exchange 
PK 
Pharmacokinetics 
PP 
Per protocol 
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PT 
Prothrombin time 
PTT 
Partial thromboplastin time 
QC 
Quality control 
RBC 
Red blood cells 
RICO 
Ristocetin cofactor activity 
RIPA 
Ristocetin-induced platelet aggregation 
SAE 
Serious adverse event 
SAP 
Statistical analysis plan 
SAR 
Serious adverse (drug) reaction 
Sβ100 
Protein S-100 beta 
s.c. 
Subcutaneous(ly) 
SD 
Single dose 
SRT 
Simple reaction time 
SUSAR 
Suspected and unexpected serious adverse reactions 
t1/2 
Terminal phase half-life 
tmax 
Time to reach Cmax 
TnI 
Troponin I 
TnT 
Troponin T 
TRALI 
Transfusion related acute lung injury 
TTP 
Thrombotic thrombocytopenic purpura 
ULN 
Upper limit of normal 
ULvWF 
Ultra large vWF 
VMEM 
Visual memory 
vWD 
von Willebrand disease 
vWF 
von Willebrand factor 
Vz 
Volume of distribution 
WBC 
White blood cells 
WFI 
Water for injection 
WHO 
World health organisation 
WLL/DR 
Word list learning and delayed recall 
WLL/SR 
Word list learning and selective reminding 
WMEM 
Working memory 
 
Nanobody® is a registered trademark of Ablynx NV. 
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LIST OF TABLES 
 
Table 1: 
Dosage, method of administration and treatment duration. .............................. 22 
Table 2: 
Overview and current status of clinical trials with anti-vWF Nanobody. ............ 33 
Table 3: 
Extent of exposure for anti-vWF Nanobody. ..................................................... 34 
Table 4: 
Safety summary of Phase I trials with i.v. administration of anti-vWF 
Nanobody. ....................................................................................................... 36 
Table 5: 
Dosing schedule for Phase I trial with ALX-0081 by s.c. administration. ........... 37 
Table 6: 
Summary of main PD results (number (%) of subjects with event). .................. 38 
Table 7: 
Summary of main safety results (number (%) of subjects with event, both 
related and unrelated events)........................................................................... 39 
Table 8: 
Dosage, method of administration and treatment duration. .............................. 65 
Table 9: 
General schedule of study assessments. ......................................................... 70 
Table 10: 
Schedule of assessments at screening and baseline measurements. .............. 75 
Table 11: 
Schedule of assessments during treatment phase. .......................................... 80 
Table 12: 
Schedule of assessments during treatment phase in case of exacerbation. ..... 82 
Table 13: 
Schedule of assessments during follow-up. ..................................................... 86 
Table 14: 
Schedule of assessments during daily PE for the treatment of a relapse. ........ 88 
Table 15: 
Modified ITP bleeding score. ............................................................................ 97 
 
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LIST OF FIGURES 
 
Figure 1: 
Treatment flow chart. ....................................................................................... 19 
Figure 2: 
Therapeutic window of ALX-0081, ReoPro® and Plavix® in a baboon model. ... 29 
Figure 3: 
Effect of ALX-0081 on platelet adhesion to ULvWF. ......................................... 30 
Figure 4: 
Treatment flow chart. ....................................................................................... 51 
Figure 5: 
Schematic overview of pre-treatment, treatment and follow-up phase. ............. 69 
 
 
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LIST OF APPENDICES 
 
14.1 
Appendix 1: Declaration of Helsinki ................................................................ 122 
14.2 
Appendix 2: Common Terminology for Adverse Events v4.0 (CTCAE) .......... 126 
14.3 
Appendix 3: Elements of Informed Consent ................................................... 126 
 
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1. 
STUDY SYNOPSIS 
 
Study Title 
A Phase II, single-blind, randomised, placebo-controlled trial to study the efficacy and safety 
of anti-von Willebrand factor Nanobody administered as adjunctive treatment to patients with 
acquired thrombotic thrombocytopenic purpura 
 
Study Number: ALX-0681-2.1/10 
 
Study Phase: II 
 
Study Centre and Patients 
This is a multicentre, multinational study in which it is anticipated to include 110 patients with 
acquired thrombotic thrombocytopenic purpura (TTP) in approximately 53 participating sites 
in approximately 13 countries in Europe, Middle East, Australia and Northern America.  
This population includes symptomatic patients with acute episodes of acquired TTP, 
requiring treatment with plasma exchange (PE). 
 
Objectives 
 
Primary  
• 
Reduction of time-to-response, defined by the achievement of laboratory blood 
marker response, confirmed at 48 hours after the initial reporting of this response 
 
Secondary (including longer-term disease sequelae) 
• 
Improvement in number of subjects responding to therapy 
• 
Reduction in PE procedure-related items  
• 
Reduction of time to resolution or improvement of signs and symptoms typical of TTP, 
including blood markers 
• 
Reduction of number of exacerbations (defined as recurrent thrombocytopenia 
following a response and requiring a re-initiation of daily PE treatment after ≥ 1 day 
but ≤ 30 days after the last daily PE) and relapses (defined as de novo event of TTP 
that occurs later than 30 days after the last daily PE)1,2 
• 
Improvement of cognitive level at steady state post acute phase 
• 
Improvement of clinical symptoms and organ function  
• 
Reduction in mortality within the PE treatment period and within the subsequent study 
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drug treatment period (including tapering) 
• 
Reduction of concomitant treatment-related complications 
• 
Evaluation of safety and immunogenicity of adjunctive treatment with ALX-0081 
• 
Determination of pharmacokinetic (PK) and pharmacodynamic (PD) characteristics of 
ALX-0081 in patients with acquired TTP 
 
Endpoints 
 
Primary Endpoint 
 
• 
Time-to-response, based on the following criteria:  
− 
Recovery of platelets ≥ 150,000/µL 
− 
This response must be confirmed at 48 hours after the initial reporting of 
platelet recovery equal to or above 150,000/µL by a de novo measure of 
platelets ≥ 150,000/µL and lactate dehydrogenase (LDH) ≤ 2 X upper limit of 
normal (ULN) (i.e. “confirmed platelet response”) 
 
Secondary Endpoints  
 
All endpoints achieved within 30 day period after end of study drug treatment: 
• 
Number of subjects with complete remission (defined as confirmed platelet response 
and absence of exacerbation)1,2 
• 
Number 
of (subjects 
with) 
exacerbations 
of TTP 
(defined as 
recurrent 
thrombocytopenia following a confirmed platelet response and requiring a re-initiation 
of daily PE treatment after ≥ 1 day but ≤ 30 days after the last daily PE), and time to 
first exacerbation of TTP 
• 
Number of subjects relapsing of TTP (defined as de novo event of TTP that occurs 
later than 30 days after the last daily PE) 
• 
Number of daily PE sessions, number of plasma units administered and number of 
days of daily PE 
• 
Resolution of non-focal neurological symptoms as defined by neurocognitive function 
at complete remission, measured by a neurocognitive test battery 
• 
Resolution or improvement (improvement of ≥ 1 grade in the Common Terminology 
Criteria for Adverse Events (CTCAE) v4.0 scale) of TTP-related signs and symptoms 
as captured on physical examination and as adverse events, at complete remission 
and at end of the study drug treatment period (including tapering) (by number of 
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unique subjects and by total number of adverse events (AEs)) 
• 
Total mortality within the PE treatment period and within the subsequent study drug 
treatment period (including tapering) 
• 
Incidence of PE treatment-related AEs, such as, but not restricted to: haemorrhage 
from catheter insertion, sepsis, catheter thrombosis, pneumothorax, fluid overload, 
hypoxia, hypotension, anaphylactoid reactions and transfusion related acute lung 
injury (TRALI) 
• 
Incidence and severity of ALX-0081 treatment-emergent AEs and relationship to 
study drug 
• 
Development of anti-drug antibodies (ADA) ≤ 30 days post-last study drug treatment 
• 
PK and PD profile 
 
Tertiary Endpoints 
 
 
 
 
 
 
 
 
 
 
 
 
Study Design 
This is a Phase II multicentre, single-blinded, parallel design, randomised, placebo-controlled 
study. 
 
After confirmation of eligibility to study participation, subjects will be randomised in a ratio of 
1:1 to either receive ALX-0081 or placebo as adjunctive therapy to PE (Figure 1). 
 
 
 
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Figure 1: 
Treatment flow chart. 
First PE on study: see section 4.2 
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Subjects will receive a first intravenous (i.v.) bolus of 10 mg ALX-0081 or placebo via push 
injection within 6h, but not later than 15 minutes prior to the initiation of PE on study (which 
can either be the very first PE session, if the subject was randomised prior to the initiation of 
PE, or the second PE session, if the subject was randomised after one, single PE session; 
see section 4.2). This first PE on study is followed by subcutaneous (s.c.) administration of 
10 mg study drug. 
Subsequently daily s.c. administrations of 10 mg ALX-0081 (Table 1) or placebo will follow 
each PE session for the duration of PE (including tapering and PE given for exacerbations) 
and once daily for 30 days following the very last PE (including tapering) (Table 1). The 
maximum total daily dose of study drug is 10 mg when administered in conjunction with PE 
(20 mg only in case twice daily PE sessions are needed) and 10 mg when in the period 
following the very last PE (including tapering). Study drug administration will continue in case 
of re-initiation of PE for an exacerbation of TTP, with a maximum total treatment duration 
limited to 90 days after first administration of study drug.   
At ≤ 30 days after the last day of study drug administration, subjects will be assessed for the 
primary and secondary endpoints of the study, and will be followed for a maximum of 1 year 
for relapses and other tertiary 
 endpoints.  
 
Laboratory parameters for inclusion, study conduct, safety assessments and assessments of 
response/relapse, re-treatment and study medication dose modification will be assessed at 
each local site laboratory.  
 
An independent Data Safety Monitoring Board (DSMB) will monitor accruing safety data 
during the study (SAEs on an ongoing basis and ‘early safety look’ when 16 subjects, 8 
ALX-0081 treated and 8 placebo-treated, have completed treatment with study drug) and will 
make recommendations on continuation of the study as appropriate. An interim analysis for 
safety with formal stopping rules is foreseen when 28 of the ALX-0081 treated subjects have 
been treated, and will make a recommendation on study continuation or discontinuation. No 
review of efficacy data by the DSMB is foreseen.  
 
Planned Sample Size 
It is anticipated to include 110 patients with acquired TTP. 
 
Study Period 
• 30 months recruitment period is anticipated. 
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• 12 months of follow-up after last administration of study drug (until last subject 
completes the 12-month follow-up visit). 
 
Duration of Treatment and Follow-up 
Treatment with study drug will be continuous during the full time interval of PE and for 30 
days after the very last PE (including tapering and PE given for exacerbations). Study drug 
administration will continue in case of re-initiation of PE for an exacerbation of TTP, with a 
maximum treatment duration limited to 90 days after first administration of study drug. 
Subjects will be followed for 12 months after last administration of study drug. 
 
Study Medication 
 
ALX-0081, anti-von Willebrand factor (vWF) Nanobody  
ALX-0081 is a clear, colourless solution formulated as a solution for injection. It is provided in 
sterile, preservative-free, non-pyrogenic, single-use 2R glass vials with injection stoppers 
and light blue aluminum crimped caps. One vial contains 2.4 mL solution for injection. One 
mL solution for injection contains as active ingredient 5 mg of ALX-0081 (INN: 
caplacizumab). 
 
Excipients 
Water for injection (WFI), potassium chloride (KCl), potassium dihydrogen phosphate 
(KH2PO4), disodium monohydrogen phosphate (Na2HPO4x2H2O), sodium chloride (NaCl), 
Glycine, Polysorbate 80 
 
Placebo 
Placebo is provided in 2R glass vials. One vial contains 2.4 mL solution for injection with 
identical excipients as ALX-0081. 
 
Storage and Stability 
ALX-0081 and placebo are delivered and stored deep frozen at –20°C (± 5°C) in the original 
outer package to be protected from light. Stability studies showed that ALX-0081 is stable at 
-20°C for at least 3 years and can therefore be stored under these conditions at the 
investigative site. ALX-0081 contains no antimicrobial preservatives. The study drug must not 
be used after the expiry date indicated on the labels of the outer package. 
 
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Dosage, Method of Administration and Duration 
 
Dosage, method of administration and duration of treatment are summarised in Table 1. 
 
Table 1: 
Dosage, method of administration and treatment duration. 
First study drug administration is 10 mg as an i.v. bolus, administered by a push injection, 15 
minutes to 6 hours prior to initiation of PE on study.* This first PE on study is followed by 
subcutaneous (s.c.) administration of 10 mg study drug. 
* As discussed in section 4.2, one PE session prior to randomisation is allowed. In such case, the second PE 
session will be the first PE on study. 
 
S.c. study drug administration during treatment phase with PE 
Frequency of PE 
Treatment administration - daily 
1 PE/day 
Administer 10 mg study drug within 30 min after end of PE 
2 PEs/day 
• For subjects receiving anti-vWF Nanobody: administer 10 mg study 
drug within 30 min after each PE  
• For subjects receiving placebo, maintain a once daily dosing regimen 
Tapering (< 1 PE/day) 
Daily administration of 10 mg study drug. On days with PE: within 30 min 
after end of PE; on days without PE at 24 h (± 1 h) after previous 
administration 
 
S.c. study drug administration (in hospital and at home) for 30 days after the very last PE (including 
tapering and PE given for exacerbations)*: 10 mg study drug once daily. 
*  As discussed in section 7.2, in case of exacerbation of TTP, standard treatment (PE) should be re-initiated and 
daily administration of study drug continued. The “study drug post-PE” period (for 30 days after the very last 
PE) will recommence once PE is again stopped. Maximum treatment duration with study drug will be limited to 
90 days after first administration of study drug. 
 
If clinically relevant bleeding* occurs 
• Stop study drug administration and continue PE if clinically indicated and applicable 
• Assess vWF:Ag and Factor VIII (FVIII) levels**. If FVIII < 10%, assess for anti-FVIII antibodies and 
if presence is confirmed, permanently discontinue study drug. 
• If vWF:Ag and/or FVIII levels are at a clinically significant low level, initiate i.v. Haemate-P 50 U/kg 
(or equivalent antihaemophilic factor/vWF complex) 
• i.v. Haemate-P treatment should be discontinued when bleeding has clearly stopped and when 
vWF > 50% 
• Restart study medication at 10 mg daily when bleeding has clearly stopped and when vWF > 50% 
and FVIII levels are within normal range 
*  Clinically relevant bleeding is defined as moderate to severe (including life-threatening) bleeding requiring 
urgent medical and/or surgical intervention.  
** FVIII chromogene or other measure of FVIII activity 
 
Criteria for Evaluation 
 
Clinical Outcome 
• 
Time-to-response of treatment, defined by a recovery of platelets ≥ 150,000/µL. This 
response must be confirmed at 48 hours after the initial reporting of platelet recovery 
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above 150,000/µL by a de novo measure of platelets ≥ 150,000/µL and LDH ≤ 2 X 
ULN  
• 
Number of subjects with complete remission 
• 
Number of (subjects with) exacerbations of TTP and time to first exacerbation of TTP. 
Number of subjects relapsing of TTP, and time to first relapse of TTP 
• 
Daily PE data, including serious adverse events (SAEs) related to daily PE treatment 
• 
Neurocognitive function, as measured by a neurocognitive test battery. This test will 
be preceded by the Glasgow Coma Score to measure the state of consciousness of 
the subject 
• 
Improvement of organ dysfunction and improvement of TTP related signs and 
symptoms 
• 
Total mortality  
• 
Determination of biomarkers of TTP including but not limited to disintegrin-like and 
metalloprotease with thrombospondin repeats 13 (ADAMTS13) levels and anti-
ADAMTS13 antibody titres (see also PD assessments) 
 
Safety Assessments 
• 
Incidence and severity of ALX-0081 treatment-emergent AEs and relationship to 
study drug 
• 
Monitoring of safety markers during treatment, including, but not limited to: platelet 
count and platelet activation, FVIII, activated partial thromboplastin time (aPTT), 
prothrombin time (PT), fibrinogen, haemoglobin, cardiac markers, liver function, RICO 
• 
Incidence of clinically relevant bleeding 
• 
Bleeding graded according to the modified immune thrombocytopenic purpura (ITP) 
Bleeding Score 
• 
Vital signs (blood pressure, heart rate and body temperature) 
• 
Cardiovascular monitoring 
• 
Glasgow Coma Score 
• 
Immunogenicity: development of ADA 
 
PK assessment 
Predose plasma concentrations against time will be plotted to demonstrate attainment of 
steady state. 
The plasma concentration-time data of ALX-0081 will be analysed using population PK 
modeling. Typical population values of basic PK parameters will be estimated together with 
the inter-individual variability. Effects of subject demographics, laboratory parameter values, 
and other covariates on the pharmacokinetics of ALX-0081 will be explored. The results of 
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the population PK analyses will be reported separately in an independent Modeling and 
Simulation report. 
 
PD assessments 
• 
RICO (conducted at central lab) 
• 
vWF, including vWF:Ag and vWF propeptide (conducted at central lab) 
• 
FVIII chromogene (conducted at central lab) 
 
Inclusion Criteria 
1. 18 years of age or older 
2. Men or women willing to accept an acceptable contraceptive regimen 
3. Patients with clinical diagnosis of TTP 
4. Necessitating PE (one, single PE session prior to randomisation into the study is 
allowed) 
5. Subject accessible to follow-up 
6. Obtained, signed and dated informed consent  
 
Exclusion Criteria 
1. Platelet count greater or equal to 100,000/µL 
2. Severe active infection indicated by sepsis (requirement for pressors with or without 
positive blood cultures) 
3. Clinical evidence of enteric infection with E. coli 0157 or related organism 
4. Anti-phospholipid syndrome 
5. Diagnosis of disseminated intravascular coagulation (DIC)  
6. Pregnancy or breast-feeding 
7. Haematopoietic stem cell or bone marrow transplantation-associated thrombotic 
microangiopathy 
8. Known congenital TTP  
9. Active bleeding or high risk of bleeding 
10. Uncontrolled arterial hypertension 
11. Known chronic treatment with anticoagulant treatment that can not be stopped safely, 
including but not limited to: 
• 
vitamin K antagonists 
• 
heparin or low molecular weight heparin (LMWH) 
• 
non-acetyl salicylic acid non-steroidal anti-inflammatory molecules 
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12. Severe or life threatening clinical condition other than TTP that would impair 
participation in the trial 
13. Subjects with malignancies resulting in a life expectation of less than 3 months  
14. Subjects with known or suspected bone marrow carcinosis 
15. Subjects who cannot comply with study protocol requirements and procedures.  
16. Known hypersensitivity to the active substance or to excipients of the study drug 
17. Severe liver impairment, corresponding to grade 3 toxicity defined by the CTCAE 
scale. For the key liver parameters, this is defined as follows: 
• 
bilirubin > 3 x ULN (need to differentiate isolated increase in indirect bilirubin 
due to haemolysis, this is not an exclusion parameter, but disease related) 
• 
alanine aminotransferase/aspartate aminotransferase (ALT/AST) > 5 x ULN 
• 
alkaline phosphatase (AP) > 5 x ULN 
• 
gamma glutamyl transpeptidase (GGT) > 5 x ULN 
18. Severe chronic renal impairment, as defined by GFR < 30 mL/min 
 
Statistical Methods 
The primary endpoint (i.e. time-to-response of blood markers comprising recovery of 
platelets ≥ 150,000/µL) will be formally assessed by means of a survival analysis. Descriptive 
statistics for efficacy parameters and secondary/tertiary endpoints (including safety, PK and 
PD analysis) will be presented for all available data, using either the intention-to-treat (ITT) 
population, the safety population, or the per protocol (PP) population. Additional information 
on the study populations that will be included is available in Section 10. A Statistical Analysis 
Plan (SAP) will be prepared before closing the database and will comprise all methods and 
tests applied for analysis of the data.  
 
Description of Study Days and Schedules of Assessments 
See Table 9 for a general overview of study assessments. Assessments at screening, during 
the treatment phase and during the follow-up phase are listed in Table 10, Table 11 and 
Table 13 in Section 8.1, respectively.  
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2. 
BACKGROUND INFORMATION 
 
2.1 
Introduction 
 
2.1.1 
Role of vWF in Platelet Aggregation  
 
The multimeric plasma protein vWF is essential for recruiting circulating platelets to the 
damaged vessel wall upon vascular injury. This recruitment is mediated through binding of 
the vWF A1-domain with the platelet receptor glycoprotein GPIb-IX-V. 
Upon expression by endothelial cells, vWF is secreted into the circulation as ultra-large 
multimers or ultra-large vWF (ULvWF). These multimers are processed into smaller regular 
sized multimers through enzymatic cleavage by ADAMTS13. In these regular sized 
multimers of vWF, the GPIb-IX-V platelet receptor binding site in the A1 domain is cryptic 
and will not spontaneously react with platelets. A conformational activation of the GPIb-IX-V 
platelet receptor binding site in the A1 domain is triggered by immobilisation or under 
conditions of shear stress. This then results in platelet adhesion and subsequently in 
thrombus formation. 
 
2.1.2 
Role of vWF and vWF Processing in Pathophysiology of TTP 
 
TTP is a rare and life-threatening disorder of the blood coagulation system, in which 
accumulation of ULvWF multimers has been implicated, leading to an increased risk of 
thrombus formation in small blood vessels due to excessive platelet aggregation. The 
condition is characterised by systemic platelet aggregation in the microcirculation, producing 
fluctuating ischaemia in many organs. If sustained, this may cause tissue infarction, 
associated with profound thrombocytopenia and erythrocyte fragmentation. 
ULvWF multimers have the natural ability to spontaneously interact with the platelet receptor 
GPIb-IX-V. In healthy subjects, these ULvWF multimers are immediately processed into 
regular sized vWF multimers via cleavage by ADAMTS13. However, in patients with TTP, 
processing of the ULvWF multimers is impaired, resulting in the persistence of the 
constitutively active A1 domain of the ULvWF which readily interacts with the GPIb-IX-V 
platelet receptor. This eventually results in formation of the characteristic blood clots found in 
the TTP patient population. 
 
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2.1.3 
Role of vWF in Other Pathologies 
 
Coronary heart disease 
In patients without impairment of vWF processing, the initial pro-thrombotic activity of the 
ULvWF multimers is immediately pacified by their processing into regular sized multimers via 
cleavage by ADAMTS13. The resulting regular sized multimers have an inactive A1 domain 
which becomes only “reactivated” for binding the platelet GPIb-IX-V receptor upon 
immobilisation and through a conformational change under shear stress. This “reactivation” 
of the A1 domain becomes a critical component in the unwanted thrombus formation in 
patients with coronary heart disease undergoing a percutaneous coronary intervention (PCI) 
procedure. In coronary arteries, blood flow conditions are recognised as high shear, which 
triggers the said conformational change of the A1 domain in regular sized vWF-multimers, 
resulting in platelet adhesion to the injury of the coronary artery vessel wall (caused by the 
PCI procedure) and subsequent thrombus formation. Therefore, Ablynx also performed 
clinical studies to develop ALX-0081 for the prevention of thrombosis in coronary heart 
disease, and more specifically acute coronary syndrome (ACS). 
 
von Willebrand disease 
In von Willebrand disease (vWD), there are 3 kinds of disorders. Type 1 of the disease is 
pertinent when the vWF is quantitatively reduced, but not absent, with a resulting 
symptomatology that consists of non-severe mucosal bleeding or bruising. Type 2 vWD 
concerns patients who carry gene mutations/deletions resulting in qualitatively abnormal 
vWF. A subcategory of Type 2 patients (Type 2N), have genetic alterations provoking a 
markedly decreased binding affinity for FVIII. Type 2, with the exception of Type 2N, has 
variable bleeding, usually mild to moderate and is in general restricted to limited bruising and 
mucosal bleeding. In Type 3 vWD virtually no vWF is present. In patients with Type 2N and 
Type 3 vWD the carrier function of vWF for FVIII is compromised. These patients may 
present with severe bleeding phenotype resembling haemophilia A, mainly provoked by the 
loss of FVIII. In symptomatic patients (i.e. Type 2N and 3) or in cases where clinical 
interventions could lead to an increased bleeding risk (i.e. tooth extraction, surgeries) vWF 
concentrate is used as therapeutic, stabilising the patient’s bleeding risk and restoring the 
normal function of vWF/FVIII-mediated haemostasis.  
 
2.2 
ALX-0081, anti-vWF Nanobody 
  
ALX-0081 is a bivalent Nanobody, consisting of two identical monovalent building blocks, 
that target vWF. ALX-0081 is able to interact with vWF in both its active (i.e. functional for 
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interaction with GPIb-IX-V as regular size multimers and as ultra-large multimers) and in its 
inactive stage (regular size multimers prior to conformational change of A1 domain). 
Nanobodies are therapeutic proteins based on the smallest functional fragments of heavy 
chain antibodies, occurring in the Camelidae family. They have a high degree of sequence 
and structural homology to human immunoglobulin VH domains. 
ALX-0081 avidly binds to its vWF multimeric target, thereby blocking the interaction of any 
sizes and activation stages of multimeric vWF with the GPIb-IX-V platelet receptor. The 
interaction of ALX-0081 with vWF is highly specific and it does not interact with human blood 
cells or platelets. Furthermore, its interference with the platelet GPIb-IX-V receptor is 
selectively through the binding of the vWF A1 domain and it does not affect the capacity of 
vWF to interact with fibrillar collagens or with collagen type VI. The Nanobody does not affect 
the activity of the vWF-protease ADAMTS13, nor does it interfere with the binding of FVIII to 
vWF. 
In in vitro assays with plasma from TTP patients, ALX-0081 selectively inhibits the interaction 
of the constitutively active A1 domain in the ULvWF multimers with the platelet GPIb-IX-V 
receptor. Therefore it prevents the characteristic platelet string formation, typical of TTP, 
which constitutes of small thrombi leading to platelet agglutination in the microvasculature, 
resulting in local ischaemia and platelet consumption. 
Given the established role of the interaction between vWF and platelet GPIb-IX-V in the 
pathogenesis of TTP, it is anticipated that ALX-0081 may provide a new option for the 
treatment of this condition. Therefore, targeting the activity of ULvWF and preventing the 
interaction with GPIb-IX-V is an attractive concept for treatment and prevention of thrombotic 
complications in TTP. 
 
2.3 
Nonclinical Study Data 
 
This section gives an overview of the most relevant pharmacological, pharmacokinetic and 
toxicological properties of ALX-0081. See the Investigator’s Brochure for full details on the 
nonclinical development of ALX-0081. 
 
2.3.1 
Pharmacology 
 
The affinity of ALX-0081 for the vWF A1-domain was estimated with a Biacore assay at 
< 10 pM. The efficacy of ALX-0081 was studied in vitro and showed that ALX-0081 is able to 
inhibit platelet adhesion to collagen specifically under high shear conditions and block 
ristocetin-induced platelet aggregation (RIPA) with a complete inhibition at a concentration of 
~ 0.4 µg/mL. 
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ALX-0081 cross-reacts with vWF of baboon, cynomolgus monkey and guinea pig and 
therefore these species are suitable for PD and toxicological studies. In tissue cross 
reactivity studies using immunohistochemistry on human, cynomolgus monkey and guinea 
pig tissues, no unexpected staining was observed.  
The efficacy and safety of ALX-0081 was investigated in vivo in a modified Folts’ model for 
stable angina in baboons. In all of the animals tested, the antithrombotic activity of ALX-0081 
was stronger than that observed for Plavix® (clopidogrel), Aspirin® (acetylsalicylic acid) and 
Heparin® (heparin). Similar efficacy of ALX-0081 was observed compared to the potent 
antithrombotic drug ReoPro® (Abciximab). The plasma concentration of ALX-0081 in 
baboons required for full inhibition of thrombus formation was between 0.3 and 0.5 μg/mL. A 
bleeding model involving measurement of the amount of blood from a well defined wound in 
baboons showed less bleeding with ALX-0081 than with Plavix® or ReoPro® even at doses 
exceeding the effective dose 10-fold. These results clearly demonstrate that the therapeutic 
window of ALX-0081 is much wider compared to the current marketed drugs Plavix® and 
ReoPro® (Figure 2) 
0
20
40
60
80
100
1
10
100
1000
10000
100000
Dose [ug /kg] 
Efficacy [%]
0
2
4
6
8
10
12
14
16
18
Surgical bleeding
ALX-0081 efficacy
Reopro efficacy
Plavix efficacy
ALX-0081 bleeding
Reopro bleeding
Plavix bleeding
 
Figure 2: 
Therapeutic window of ALX-0081, ReoPro® and Plavix® in a baboon model.  
 
Efficacy expressed as % inhibition of cyclic flow reductions in a modified Folts’ 
model and safety expressed as n-fold increase bleeding from a well defined 
incision compared to a control level is shown in function of dose administered. 
 
The antithrombotic activity of ALX-0081 in baboons is of short duration (several hours) and it 
can be reversed by administration of vWF, indicating that vWF can be used as an antidote 
for ALX-0081. 
Due to the lack of a relevant animal model, no in vivo efficacy of ALX-0081 to neutralise 
ULvWF was demonstrated. Initial in vitro data using plasma from TTP patients in flow 
chamber experiments point towards therapeutic potential of ALX-0081 in the TTP setting. In 
these experiments, endothelial cells were stimulated to produce ULvWF strings on their 
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surface. These strings support adhesion of platelets even under static and low shear 
conditions (Figure 3A). In the presence of normal plasma the ULvWF strings are rapidly 
cleaved by the protease activity of ADAMTS13, whereas in plasma from patients with TTP 
platelet deposition to the vWF strings is retained due to the lack of functional ADAMTS13 
(Figure 3B). Importantly, ALX-0081 added to the TTP plasma completely blocks platelet 
deposition (Figure 3C), thereby demonstrating that ALX-0081 not only inhibits the regular 
sized vWF multimers but also ULvWF released by endothelial cells. However, if platelets 
were allowed to form platelet strings prior to ALX-0081 addition, ALX-0081 was not able to 
detach these platelets.3  
 
Figure 3: 
Effect of ALX-0081 on platelet adhesion to ULvWF. 
 
Images captured from real-time video microscopy: captures of platelets 
perfused over stimulated endothelial cells under conditions of low shear stress 
(300s-1). Platelets resuspended in buffer (A) or in plasma from TTP patients (B) 
adhere to ULvWF thereby forming platelet strings (red arrows) on the surface of 
endothelial cells. In the presence of plasma from TTP patients, ALX-0081 
completely abolishes the platelet interaction with ULvWF (C). 
 
2.3.2 
Pharmacokinetics 
 
ALX-0081 shows a non-linear kinetic profile. In all species, a first phase characterised by a 
rapid decline in plasma levels can be described at the higher doses immediately after 
administration (i.v.) or after peak plasma levels are reached (s.c./intramuscular [i.m.]). This is 
thought to be caused by rapid distribution of the unbound drug in combination with rapid 
elimination via renal clearance (glomerular filtration). In cross-reactive species this decline is 
followed by a second phase.4,5 The terminal half-life (t1/2) of ALX-0081 -more precisely 
ALX-0081 bound to vWF- ranges between 5-36 hours across the relevant species. A 
biodistribution study with radiolabelled ALX-0081 supported this hypothesis and clearly 
showed that ALX-0081 bound to vWF follows a hepatic clearance pathway, whereas 
unbound drug is excreted via the kidneys.6  
Since excess ALX-0081 over a vWF occupancy ratio of 1 is cleared rapidly, trough drug 
concentrations did not increase significantly even upon multiple administrations at high doses 
in toxicology studies, again pointing towards a low potential for accumulation. Clinical 
anticipated administration routes are i.v. and s.c. The absolute bioavailability of ALX-0081 
after s.c. administration, in cynomolgus monkey, ranged from 82 to 97%.7  
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2.3.3 
Toxicology 
 
Currently, the toxicology program for ALX-0081 consists of single dose (SD) toxicity studies 
both in cynomolgus monkey (i.v. and s.c.) and guinea pig (i.v.), 2-week repeated dose 
toxicity studies in cynomolgus monkey (i.v., s.c.) including safety pharmacology assessment 
and 13-week repeated dose toxicity studies in guinea pig and cynomolgus monkey with an 8-
week recovery including safety pharmacology and fertility functional assessment. Local 
tolerance was assessed separately in rabbit.  
 
The pivotal toxicology studies were performed for 13- week duration in cynomolgus monkey 
and guinea pig as the non-rodent and rodent species, respectively. In both studies, animals 
were given s.c. 4 times daily doses of ALX-0081 at 6 hour intervals (0, 0.1, 1 or 10 mg/kg per 
dose) for 13 weeks.  
Data obtained during the in life phase show that vWF/FVIII levels were decreased with a 
non-cumulative pharmacology effect in cynomolgus monkey and guinea pig (FVIII only), with 
a mean maximum decrease from individual baseline of FVIII of 84 % in all dose groups in 
cynomolgus monkey. The complete data set including recovery phase is under assessment. 
In guinea pig, FVIII decreases with a mean of 47.0% (preliminary data reported for 13-week 
toxicity study, raw data without QC).  
Full neutralisation of vWF activity, defined as below the limit of detection, was demonstrated 
by RICO assays (PD marker) in both guinea pig and cynomolgus monkey (preliminary data 
analysis). 
Clinical observations in the 13-week toxicity study in cynomolgus monkey revealed slight to 
fairly severe haematomas and swellings at the injection sites in a dose-related manner. 
Macroscopic examination at necropsy revealed haemorrhagic s.c. tissue at the injection sites 
in several ALX-0081-treated animals of all dose groups. In addition, slightly increased 
bleeding at injection sites was recorded in one male (4 mg/kg/day) and two females (4 and 
40 mg/kg/day). The same female at 4 mg/kg/day showed exaggerated menstrual bleeding on 
Day 30 and the same female at 40 mg/kg/day had a nose bleed. All bleeding events were 
described to be related to the pharmacological effect of ALX-0081.  
In the 13-week toxicity study in guinea pig, no ALX-0081 treatment related adverse effects 
were observed in clinical signs, water and food consumption, body weight, clinical pathology 
parameters and urinalysis. Macroscopic examinations at necropsy revealed haemorrhagic 
s.c. tissue at the injection sites in all dose groups. The observations are similar to those seen 
in cynomolgus monkey. Incidence and severity increased with dose and the observed effects 
were also considered to be related to the pharmacological effect of ALX-0081.  
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There were no ALX-0081 treatment-related effects on electrocardiogram (ECG) and organ 
weight. No changes in ophthalmological and auditory parameters were noted in both guinea 
pig and cynomolgus monkey. 
In summary, these findings confirms that even at high doses (and exposures) effects on FVIII 
levels are within expected ranges, the clinical observations in the nonclinical species 
correlate with the minor findings in clinical trials so far and that continuous treatment with 
high doses of ALX-0081 might lead to symptoms which resemble the mild vWD type 1 and 2.  
 
A GLP embryo-fetal developmental toxicity study in guinea pigs has been conducted. No 
embryo-fetal toxicity and no teratogenic potential have been observed. The no observed 
adverse effect level (NOAEL) was higher than 20 mg/kg/day since no adverse effects were 
observed. 
 
Local tolerance has been studied in rabbits, by administration via the i.v., s.c., i.m., intra-
arterial (i.a.) and paravenous routes in doses up to 1.2 mg/kg b.w. administered in 0.5 mL/kg. 
No test item-related alterations were observed. 
 
Immunogenicity was evaluated during toxicology studies in guinea pig and cynomolgus 
monkey. In general, ADA could be detected in a limited subset of animals after i.v or s.c. 
single or multiple dose (MD) administration in both species, which did however not 
compromise the exposure. Moreover, PD markers were not affected by measured ADA in 
any of the studies, indicating indirectly that these antibodies were not neutralising the activity 
of ALX-0081. 
 
In conclusion, ALX-0081 has been well tolerated in guinea pig and cynomolgus monkey used 
as relevant toxicology animal species as a consequence of (i) high target specificity (ii) a 
mode of action specific for pathological conditions and (iii) a unique self-regulating PK profile 
which leads to rapid clearance of excess drug.  
 
2.4 
Clinical Experience 
 
Currently, Ablynx is developing anti-vWF Nanobody for the treatment of TTP. For full details 
on the clinical development of ALX-0081, see the Investigator’s Brochure. 
Completed and ongoing clinical trials with anti-vWF Nanobody are listed in Table 2. 
 
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Table 2: 
Overview and current status of clinical trials with anti-vWF Nanobody. 
Study number 
(EudraCT N°) 
Study title 
Phase Status 
Clinical trials supporting ACS indication 
ALX-0081-01/06 
(2006-006502-28)8 
A Phase I, double blind, randomized, placebo-
controlled, parallel group study in healthy male 
volunteers to investigate the safety, tolerability 
and 
pharmacokinetics 
of 
the 
Nanobody 
ALX-0081 
administered 
intravenously 
as 
single ascending doses 
Ia 
Completed 
ALX-0081-1.2/08 
(2007-007263-24)9  
 
A Phase I double blind, placebo controlled 
study 
of 
ALX-0081 
multiple 
dose 
administrations in stable angina patients 
undergoing PCI 
Ib 
Completed 
 
ALX-0081-2.1/09 
(2009-012206-39) 
A Phase II randomized, open label clinical trial 
in 
high 
risk 
percutaneous 
coronary 
intervention (PCI) patients receiving standard 
antithrombotic treatment plus either ALX-0081 
or GPIIb/IIIa inhibitor (ReoPro®) over a period 
of 24 hours 
IIa 
Completed (final data 
analysis and 
reporting ongoing)  
Clinical trial supporting TTP indication 
ALX-0681-1.1/08 
(2008-006624-60)10 
A Phase I study in healthy volunteers to 
investigate 
the 
safety, 
tolerability, 
pharmacokinetics and pharmacodynamics of 
anti-vWF 
Nanobody 
administered 
subcutaneously 
I 
Completed 
 
An overview of all subjects who have received one or more doses of anti-vWF Nanobody is 
provided in Table 3. 
 
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Table 3: 
Extent of exposure for anti-vWF Nanobody. 
 
 
Dose 
Duration 
(Days) 
No. Subjects 
SUBCUTANEOUS 
Healthy Volunteers 
 
 
 
ALX-0681-1.1/08 
2 mg 
1 
3 
Adults – male and female 
4 mg 
1 
3 
 
 
8 mg 
1 
3 
 
 
10 mg 
1 
3 
 
 
16 mg 
1 
3 
 
 
10 mg 
7 
6 
 
 
10 mg 
14 
6 
Total 
27 
INTRAVENOUS 
Healthy Volunteers 
 
 
 
ALX-0081-01/06 
0.5 mg x 1 infusion (1h) 
1 
3 
Adults - male 
1 mg x 1 infusion (1h) 
1 
3 
 
 
2 mg x 1 infusion (1h) 
1 
3 
 
 
4 mg x 1 infusion (1h) 
1 
3 
 
 
8 mg x 1 infusion (1h) 
1 
3 
 
 
12 mg x 1 infusion (1h) 
1 
6 
Total 
21 
Stable Angina Patients 
undergoing PCI 
 
 
 
ALX-0081-1.2/08 
2 mg x 1 infusion (1h) 
1 
3 
Adults - male and female 
4 mg x 1 infusion (1h) 
1 
3 
 
 
6 mg x 1 infusion (1h) 
1 
3 
 
 
9 mg x 1 infusion (1h) 
1 
3 
 
 
6+4+4+4 mg q6h infusions (1h) 
1 
6 
 
 
6+4+4+4 mg q6h bolus 
1 
20 
Total 
38 
High risk PCI patients 
 
 
 
ALX-0081-2.1/09 
6+4+4+4 mg q6h bolus 
1 
181 
Adults - male and female 
 
 
 
TOTAL 
267 
 
In the following sections, a summary of the setup and results for the studies listed in Table 2 
is provided.  
 
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2.4.1 
Clinical Trials Supporting ACS Indication 
 
Up to now, three clinical trials with anti-vWF Nanobody, supporting its development for the 
treatment of ACS, have been approved. The Phase Ia trial in healthy male volunteers has 
been completed successfully, as well as the SD and MD stages of the Phase Ib trial in stable 
angina patients undergoing elective PCI. An open-label extension (OLE) of the latter trial to 
evaluate administration of ALX-0081 by i.v. bolus injection compared to i.v. infusion has 
completed the treatment phase. Finally, a Phase II trial in high risk PCI patients, comparing 
ALX-0081 and ReoPro® was initiated in July 2009. 
 
The Phase Ia trial was designed to assess the safety, tolerability and PK of ALX-0081 in 
healthy male volunteers. The first dose of study medication was i.v. 500 µg ALX-0081 or 
placebo (dose level 1) followed by 2-fold, 4-fold, 8-fold, 16-fold and 24-fold of the first dose in 
dose levels 2-6, respectively. 
 
The subsequent Phase Ib study was designed to determine the maximum tolerated dose 
(MTD) and/or biologically effective dose (BED) and the Phase II recommended dose of 
ALX-0081 in ACS patients. In addition, this study aimed to determine the safety and 
tolerability of escalating doses of ALX-0081 in patients undergoing PCI and to document the 
biological and clinical response to therapy. In Stage A of the study, single ascending doses 
(2, 4, 6 and 9 mg) of ALX-0081 (n = 3 per dose level) or placebo (n = 1 per dose level) were 
administered as a 1h i.v. infusion. In the second stage of the trial (Stage B), multiple dosing 
was evaluated and subjects received an initial dose of 6 mg, followed by 3 subsequent doses 
of 4 mg every 6 hours (n = 6 ALX-0081 and n = 2 placebo). Route of administration was also 
i.v. infusion. Following Stage B, an open label extension was initiated with 22 subjects (Stage 
C) (n = 20 ALX-0081 and n = 2 placebo) in order to determine the optimal i.v. route of 
administration for ALX-0081 in man (bolus injections or 1 hour infusions). 
 
The conclusions of both trials can be summarised as follows: 
• 
Single and multiple i.v. administrations of ALX-0081 are safe and well tolerated  
• 
The BED (providing a complete inhibition of vWF-mediated platelet aggregation 
for > 24 hours) and Phase II recommended dose is a SD of 6 mg, followed by 3 
subsequent doses of 4 mg every 6 hours, given as i.v. bolus injections 
• 
RICO can be used as a reliable biomarker for the PD effect of ALX-0081, i.e. inhibition 
of vWF-mediated platelet aggregation 
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• 
In subjects receiving the BED, mean RIPA values below 10% were maintained for a 
maximum of 24 hours and clinically relevant RICO inhibition was maintained for a 
maximum of 30 hours 
• 
Non-linear PK properties were determined 
• 
Half-life values were similar after single and repeated dosing. ALX-0081 plasma 
concentration values at 6, 12, 18 and 24 hours during repeated dosing showed that 
the trough values did not increase but appeared to have reached a steady state 
• 
There were no apparent clinical differences between the treatment groups with 
regards to the number of subjects with (S)AEs, nor with regards to the AE profile 
• 
The only adverse drug reactions clearly attributable to ALX-0081 administration were 
alterations of the coagulation parameters. Mild, transient and non-dose dependent 
decreases in FVIII and vWF were observed, but were not considered clinically 
relevant. A summary of the safety findings of both trials is provided in the following 
table 
 
Table 4: 
Safety summary of Phase I trials with i.v. administration of anti-vWF Nanobody. 
Trial 
Group 
# Subj 
vWF Ag 
decrease 
FVIII 
decrease 
Bleeding 
signs 
IPR 
AEs 
SAEs 
Phase Ia 
Placebo 
19 
0 
0 
0 
1 (5%) 
1 (5%) 
0 
 
ALX-008
1 
21 
8 (38%) 
6 (29%) 
0 
3 
(14%) 
5 (24%) 
0 
Phase Ib 
Placebo 
6 + 
2OLE 
0 
2 (25%) 
2 (25%) 
3 
(38%) 
8 
(100%) 
2 
(25%) 
 
ALX-008
1 
18 + 
20OLE 
38 
(100%) 
38 
(100%) 
3 (8%) 
21 
(55%) 
33 
(87%) 
7 
(18%) 
 
• 
No immunogenic responses were detected up to 30 days after administration of 
ALX-0081 
 
Based on the results of the Phase I studies, a Phase II, randomized, open-label clinical trial 
was initiated in high risk acute coronary syndrome (ACS) patients undergoing PCI. The 
objective of the study was to compare the safety, and more specifically bleeding risk, of 
ALX-0081 versus the GPIIb/IIIa inhibitor ReoPro® (abciximab) in 364 high risk PCI patients 
(181 and 183 in the ALX-0081 and abciximab treatment groups respectively), and to assess 
tolerability, as well as biological and clinical effectiveness. 
 
The Phase II study has just been completed, and reporting is currently ongoing. Based on 
the available results, there were no significant safety concerns raised for treatment with 
ALX-0081 in this study, and the results seen were as would be expected for this patient 
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population of high risk PCI patients. For additional details and interim results of this study, 
please refer to the Investigator’s Brochure. 
 
2.4.2 
Clinical Trial Supporting TTP Indication: Phase I Study in Healthy 
Volunteers 
 
The goal of this Phase I trial (ALX-0681-1.1/08) in healthy volunteers was to determine the 
MTD or BED and the Phase II dosing and scheduling of ALX-0081, in order to support the 
further clinical development of ALX-0081 in TTP patients. 
In total, 36 healthy volunteers were included in this randomised, placebo-controlled study to 
evaluate the safety of single ascending doses and multiple doses of ALX-0081 administered 
s.c. (Table 5).  
 
Table 5: 
Dosing schedule for Phase I trial with ALX-0081 by s.c. administration. 
Cohort 
Dose (mg) 
Number of daily 
doses 
Subjects receiving  
ALX-0081 
Subjects receiving 
placebo 
SD 
 
 
 
 
Cohort 1 
2 
1 
3 
1 
Cohort 2 
4 
1 
3 
1 
Cohort 3 
8 
1 
3 
1 
Cohort 4 
16 
1 
3 
1 
Cohort 5 
10 
1 
3 
1 
MD 
 
 
 
 
Cohort 6 
10 
7 
6 
2 
Cohort 7 
10 
14 
6 
2 
 
PK results 
After s.c. administration, ALX-0081 plasma concentrations increased in all dose groups with 
a mean tmax ranging from 4 to 10 h postdose. Mean peak plasma concentrations (Cmax) were 
219.7, 385.7, 443.7, 528.0 and 611.0 ng/mL for the 2, 4, 8, 10 and 16 mg dose groups, 
respectively. Overall, half-lives were comparable within the 4 to 16 mg dose range. PK 
results from the MD part of the study show that steady state was reached already after first 
dosing. The steady-state PK parameters, after once daily repeated s.c. administration of 
ALX-0081 10 mg for 7 or 14 days, were comparable, indicating that no accumulation 
occurred. The results of the regression analysis showed no dose proportionality for Cmax and 
AUC0-24 and dose proportionality for AUClast and AUCinf. 
 
 
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PD results 
Inhibition of the biomarker RICO was observed in all doses groups ranging from 70% 
inhibition in the 2 mg dosing group to approximately 90% inhibition in the other SD groups. 
Reversal towards basal levels took place after approximately 72 h post dosing. A rapid and 
sustained inhibition of approximately 90% was observed after dosing in both MD groups. 
Values returned to basal levels at day 15 and day 22 after 7 days and 14 days MD 
respectively. In all dose groups of the SD part of the study complete RICO inhibition (defined 
as values < 20%) was observed from 4-18 h (2 mg), 12-18 h (4 mg), 4-24 h (8 mg), 4-36 h 
(10 mg) and 4-48 h (16mg) after dosing. In both groups of the MD part of the study RICO 
was completely inhibited from 2-168 h after dosing, i.e. from day 1-8 (7 day) and from 2-360 
h after dosing, i.e. day 1-16 (14 day). A summary of the main PD findings is provided in 
Table 6. 
 
Table 6: 
Summary of main PD results (number (%) of subjects with event). 
Dose level 
Subjects 
(n) 
RICO < 20%  
vWF 
< 50% 
FVIII  
< 50% 
Subjects (%) 
Start (h)* 
Stop (h)* 
SD 
 
 
 
 
 
 
2 mg 
3 
2 (67) 
2-4 
12-18 
3 (100) 
0 (0) 
4 mg 
3 
2 (67) 
4-6 
18-36 
1 (33) 
1 (33) 
8 mg 
3 
3 (100) 
2-4 
18-48 
3 (100) 
3 (100) 
16 mg 
3 
3 (100) 
1-4 
48 
0 (0) 
2 (67) 
10 mg 
3 
3 (100) 
2-6 
24-36 
3 (100) 
3 (100) 
Placebo 
5 
0 (0) 
NA 
NA 
0 (0) 
0 (0) 
MD 
 
 
 
 
 
 
10 mg (7d) 
6 
6 (100) 
2-4 
168-192 
5 (83) 
3 (50) 
Placebo (7d) 
2 
0 (0) 
NA 
NA 
0 (0) 
0 (0) 
10 mg (14d) 
6 
6 (100) 
2-4 
336-360 
5 (83) 
5 (83) 
Placebo (14d) 
2 
0 (0) 
NA 
NA 
0 (0) 
0 (0) 
* Time relative to first administration 
NA: not applicable 
 
Safety 
Overall the study drug ALX-0081 was well tolerated and there was no difference in the 
number of subjects with AEs and their respective severity between the ALX-0081 treatment 
groups and placebo. In all doses of the SD part of the study the related AEs were low and in 
all verum categories no more than 1 subject reported 1 related AE. In the MD 7 days part of 
the study, a total of 5/6 subjects (83%) reported 13 related AEs in the verum group compared 
to 2/2 subjects (100%) reporting 2 related AEs in the placebo group. In the MD 14 days part 
of the study a total of 6/6 subjects (100%) reported 46 related AEs in the verum group 
compared to 1/2 subjects (50%) reporting 1 related AE in the placebo group. A dose 
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dependency was not observed, but more related AEs were shown after longer treatment in 
the MD group of the study, including an increase of the number of bruises and bleedings, all 
being of mild intensity. All injection and puncture site reactions were of mild intensity and 
therefore clinically not relevant. The SD part of the study showed no dose relationship 
regarding incidence and severity of AEs. Since there was only one active dose level used in 
the MD part of the study no conclusions can be drawn concerning dose dependency of AEs. 
Main safety results are summarised in Table 7. 
 
Table 7: 
Summary of main safety results (number (%) of subjects with event, both related 
and unrelated events). 
Dose level 
Subjects 
(n) 
AE 
SAE 
Bleeding 
Haematoma 
at injection 
site 
Haematoma 
at blood 
sampling site 
Other 
haematoma 
SD 
 
 
 
 
 
 
 
2 mg 
3 
2 (67) 
0 (0) 
1 (33) 
0 (0) 
1 (33) 
0 (0) 
4 mg 
3 
2 (67) 
0 (0) 
1 (33) 
0 (0) 
0 (0) 
0 (0) 
8 mg 
3 
3 (100) 
0 (0) 
0 (0) 
0 (0) 
1 (33) 
0 (0) 
16 mg 
3 
3 (100) 
0 (0) 
0 (0) 
0 (0) 
0 (0) 
1 (33) 
10 mg 
3 
1 (33) 
0 (0) 
0 (0) 
0 (0) 
1 (33) 
0 (0) 
Placebo 
5 
3 (60) 
0 (0) 
0 (0) 
0 (0) 
0 (0) 
0 (0) 
MD 
 
 
 
 
 
 
 
10 mg (7d) 
6 
6 (100) 1 (17)* 
5 (83) 
1 (17) 
0 (0) 
3 (50) 
Placebo (7d) 
2 
2 (100) 
0 (0) 
1 (50) 
0 (0) 
1 (50) 
0 (0) 
10 mg (14d) 
6 
6 (100) 
0 (0) 
5 (83) 
5 (83) 
4 (67) 
5 (83) 
Placebo (14d) 
2 
2 (100) 
0 (0) 
1 (50) 
0 (0) 
0 (0) 
0 (0) 
* unrelated SAE, meniscus lesion of the knee 
 
Immunogenicity 
Anti-ALX-0081 antibody response was measured on day 1 (predose), day 7, day 60 and day 
22 for the 14 day part of the study. A total of 4 subjects had positive pre-dose assay read-
outs and 1 subject had an initial positive response at follow-up. However, no samples were 
confirmed as showing treatment emergent positive responses, indicating the absence of an 
immunogenic response to ALX-0081. 
 
Overall conclusion 
In summary it can be concluded that s.c. administration of ALX-0081 as a SD or 
administered as daily injection for up to 14 days was well tolerated and no difference could 
be detected regarding the number of subjects with AEs and their severity between 
ALX-0081- and placebo-treated subjects. All injection and puncture site reactions were of 
mild intensity and were classified as clinically not relevant. The PD parameters for 
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coagulation FVIII and vWF showed a fast and reversible decrease compared to pre-dose 
values. None of the observed decreases in FVIII were recorded as abnormal/clinically 
significant PD assessments or as AEs. Values normalised between 24 and 72 h after last 
dosing, depending on the dose. The biomarker RICO was completely inhibited in all subjects 
from a SD of 10 mg onwards for 24h, indicating biological efficacy. The biomarker was 
continuously suppressed below complete inhibition levels throughout the entire multiple 
dosing part, indicating continuous biological efficacy for > 14 days. Immunogenicity assay 
results indicated the absence of an immunogenic response to repeated daily administrations 
of s.c. ALX-0081 for up to 14 days as analysed for a minimum 45 days following completion 
of treatment. 
 
2.5 
Safety/Risk Profile 
 
The risk assessment for the application of ALX-0081 can currently be determined on the 
basis of the preclinical data available, the data from the 3 Phase I studies in healthy 
volunteers and in patients with stable angina undergoing a PCI procedure, the postulated 
mode of action, the clinical presentation of patients with vWD and the knowledge of other 
generally used antithrombotic agents. In this respect, it is noteworthy that so far, preclinical 
models have been highly predictive for the human situation in terms of PK/PD and safety. 
 
2.5.1 
Potential Risks 
 
Toxicity 
Subchronic toxicity studies of ALX-0081 (13 weeks) have been performed in cynomolgus 
monkeys and guinea pigs. In both studies the NOAEL proved to be above 4x10 mg 
ALX-0081/kg body weight, the maximum allowable volume of administrations per day for a 
guinea pig or cynomolgus monkey study. The biomarker RICO was inhibited during the 
toxicity studies, thereby indicating the absence of neutralising antibodies against ALX-0081. 
Comparing the results obtained with the 13 weeks cynomolgus monkey toxicity study with a 
fixed daily dose of 10 mg in humans, revealed a RatioAUC24 of 82, demonstrating the 
presence of wide therapeutic window. Using PK modeling a predicted human exposure of 
10.3 µg.h/mL (AUC24h) following a possible bid 10 mg administration (20 mg/subject/day) can 
be compared to exposure reached in toxicity studies with a resulting ratio of 54 for 
cynomolgus monkey. Due to the conservative correction factor applied in the exposure 
margin calculations of guinea pigs and the limitations in volume that could be administrated 
to guinea pigs, a 10-fold systemic exposure margin could not be demonstrated in the guinea 
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pigs. Importantly, the NOAEL was not reached during the subchronic toxicity study in guinea 
pigs. 
Hence the data obtained from the 13 weeks cynomolgus monkey study allow us to conclude 
that the safety margins in terms of relative systemic exposure to ALX-0081 can be 
considered as very wide. 
 
Risk for bleeding 
The most prominent risk of the currently used non-specific antithrombotic agents is an 
elevated bleeding diathesis or apparent bleeding. Beside any unexpected effects, bleeding 
also represents the most relevant safety concern for ALX-0081. In this context ALX-0081 
was investigated in a preclinical surgical bleeding model.11 In this study, surgical blood loss in 
animals receiving ALX-0081 was comparable to blood loss in Heparin® treated animals, and 
2- and 4-fold less than in Plavix® and ReoPro® treated animals, respectively. This indicates 
that ALX-0081 may be safer than Plavix® and ReoPro® in terms of bleeding risk. The 
ALX-0081 doses used in this surgical bleeding model were more than 10-fold the 
documented effective antithrombotic dose. 
 
In the 13-week and 26-week RD toxicity studies in cynomolgus monkey, anti-FVIII antibodies 
(AFA) were detected in 4 male animals with no associated clinical signs, and in one animal 
with associated haemolytic anaemia, signs of inflammation and extremely low FVIII:C 
activity. More details are included in Section 4.3 of the Investigator’s Brochure. 
 
A good understanding of the biology of vWF and the clinical presentation of patients with 
deficiency of vWF helps to understand the observations seen in the conducted preclinical 
and clinical studies and to assess the risk for bleeding appropriately. It is well known that 
most patients suffering from a deficiency of vWF (vWD) have mild-to-moderate quantitative 
deficiencies of vWF and FVIII, which are co-ordinately reduced to 5 to 30 percent of normal 
plasma levels (5 to 30 IU/dL).12 This reduction is not associated with spontaneous bleeding 
but with bleeding after surgery (which is typical of coagulopathies) and mucosal tract 
haemorrhages such as epistaxis and menorraghia (which are typical of thrombocytopathies). 
It should be taken into account that these patients have a chronic, i.e. life-long, impairment of 
vWF and their vWF levels always stay far below 30 IU/dL. These patients don’t receive 
regular prophylaxis, because their bleeding tendency is less severe. Only in patients with 
chronic and complete absence of vWF or levels below 5-10 IU/dL is a prophylaxis with vWF 
and FVIII indicated.  
 
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Since ALX-0081 interacts with the A1 domain of vWF, RICO is inhibited also during the 
toxicity studies. In addition, statistical significant drops in FVIII and vWF:Ag levels were 
observed in cynomolgus monkeys. In guinea pigs, the observed effects on FVIII were less 
pronounced. Although drops for FVIII were observed in both species, sufficient FVIII 
remained available to ensure proper coagulation (see also 2.3.3). No signs of bleeding, other 
than bruising at the injection sites were observed in the guinea pig study. In the cynomolgus 
monkeys study, slightly increased bleeding at injection sites were recorded in one male 
(4 mg/kg/day) and two females (4 and 40 mg/kg/day). Mucosal bleedings (1 exaggerated 
menstrual bleeding and 1 nose bleed) were observed in the same females. Importantly, 
although systemic exposure reached levels up to 80-fold higher than what can be expected 
in men during the Phase II trial, no signs of internal bleeding were observed. The observed 
clinical effects in cynomolgus monkeys are in line with the clinical presentation of patients 
with a mild to moderate vWD.  
From the safety data collected from the Phase I studies in healthy volunteers and patients 
with stable angina, a single i.v. administration of 0.5 mg up to 12 mg and respective multiple 
administrations up to 18 mg total dose of ALX-0081 as a short infusion over 1 hour were well 
tolerated in all participating subjects. The observed mild decreases in FVIII and vWF levels 
were expected as they indicate the biological effectiveness of the drug. None of the observed 
decreases in FVIII chromogene or vWF levels were recorded as clinically significantly. 
In healthy subjects, s.c. administration of ALX-0081 as a SD or administered as daily 
injection for up to 14 days was well tolerated and no difference could be detected regarding 
the number of subjects with AEs and their severity. All injection and puncture site reactions 
were of mild intensity and were classified as clinically not relevant. S.c. administration of 
ALX-0081 as a SD or administered as daily injection for up to 14 days resulted in a fast and 
reversible decrease of FVIII and vWF. The average decrease of vWF levels ranged from 
approximately 50% decrease in low dose groups to 70% decrease, compared to pre-dose 
level, in the high dose groups. For FVIII, a rapid average decrease can be found in all doses 
groups ranging from 30%, compared to pre-dose level, in the 2 mg dosing group to 50-65% 
in the other SD groups. Reversal takes place after approximately 72 h after dosing. A 
sustained decrease of approximately 50% can be found after dosing in both MD groups. 
Levels are back to basal levels after approximately 48 h post dosing in the MD groups. None 
of the observed decreases in FVIII were recorded as abnormal/clinically significant PD 
assessments or as AEs. 
 
In summary, in all healthy subjects and patients with stable angina, the treatment with 
ALX-0081 resulted in a rapid and reversible reduction of vWF and FVIII levels, but this 
reduction never reached the levels indicating spontaneous bleeding for patients with mild or 
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more severe forms of vWD. It is therefore expected that the further administration of 
ALX-0081 does not result in a clinically significant reduction of vWF and FVIII mandating 
prophylaxis or treatment for an imminent bleeding risk. Of note, vWF as antidote is readily 
available in the respective treatment institutions and would immediately antagonise the 
activity of ALX-0081 and Preclinical studies have demonstrated that vWF concentrates can 
indeed antagonise the activity of ALX-0081. 
 
Immunogenicity 
ALX-0081 is structurally not identical to an endogenous protein and has no agonistic 
function. Consequently, the risk for developing antibodies with potential adverse 
consequences such as the neutralisation of an endogenous protein or a hyper-agonistic 
function is considered to be low. At present, the development of ADA after i.v. and after s.c. 
administration of ALX-0081 has been evaluated in the conducted Phase I trials. I.v. treatment 
during the Phase I trials consisted of either SD treatment or MD administrations with 4 doses 
during 24 h. S.c. treatment included repeated daily administration of ALX-0081 for up to 14 
days. In none of the Phase I trials, treatment-emergent ADA were observed. During the 
planned Phase II TTP trial, ALX-0081 will be given on top of current standard of care 
treatment, thereby limiting the potential consequences of the development of ADA. For many 
of these TTP patients, immunosuppressive treatment will be part of their standard of care 
treatment. Other TTP patients carry an underlying disease (e.g. human immunodeficiency 
virus (HIV) or cancer) associated with a depressed immune status. In both groups of TTP 
patients the probability for development of ADA is anticipated to be reduced.  
 
2.5.2 
Potential Benefits 
 
Although the introduction of PE and transfusion has significantly reduced the mortality rates 
from TTP over the last three decades, the condition still carries a significant risk of mortality 
and morbidity. The mortality rate of acute bouts in acute idiopathic TTP, in patients managed 
with the current therapies remains in the order of 10% to 30%.1,13,14 In the case of secondary 
TTP, PE and transfusion are recognised to be less effective and the mortality rate is 
considerably higher. In the cases when the disease is secondary to pregnancy, in which PE 
is regarded as reasonably effective the mortality rate of an acute bout of TTP is 
approximately 25%, rising to over 40% in cases with concurrent pre-eclampsia.15 However, in 
cases secondary to, for example, underlying malignancies or bone marrow transplant the 
mortality rate remains at 40% to 60% despite the use of such treatment regimens.14,16,17 
 
 
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Potential effect of ALX-0081 on pathophysiology of TTP 
ULvWF-mediated platelet aggregation is recognised as a key element in the pathogenesis of 
idiopathic TTP both in acute disease, in refractory and relapsing patients, and in the familial 
form of the disease. In secondary TTP, although the underlying etiologies are varied, ULvWF 
also appears to play a fundamental role in the underlying pathophysiological processes that 
have been proposed to underlie the condition. The inhibition of ULvWF-mediated platelet 
aggregation represents a rational approach to treatment that may prove to be of value in the 
management of all subtypes of TTP. Given the continuing significant level of mortality from 
TTP and the observed complications of PE and transfusion, there is a clear need for the 
development of such additional therapeutic approaches to supplement, or potentially reduce 
the need for, these methods of treatment. On the basis of the available information, 
ALX-0081 may offer such an additional option to further improve the management of TTP.  
 
Potential benefit of ALX-0081 in TTP: efficacy 
The current therapy of TTP with PE and transfusion provides replacement ADAMTS13 and 
removes antibodies against the enzyme, thus progressively leading to a normalisation of 
ULvWF processing. However, this treatment requires multiple exchanges and transfusions 
over many days, during which time there is no direct pharmacological targeting of the active 
process of ULvWF-mediated platelet aggregation. ALX-0081 has been demonstrated to 
inhibit platelet-vWF interactions and particularly ULvWF-mediated platelet interaction in vitro 
and has also been shown to have no impact on ADAMTS13 function and, therefore, would 
not be anticipated to interfere with the enzyme replaced by plasma transfusion. In a modified 
Folt’s model in baboons, which represents a relevant model for ACS, ALX-0081 has been 
demonstrated to exert a strong antithrombotic effect with a lower degree of bleeding 
compared with other antithrombotic agents. In an initial Phase I study, ALX-0081 has been 
demonstrated to inhibit ristocetin induced platelet aggregation (a vWF-mediated process) in 
the blood of healthy volunteers. 
On the basis of these findings, it can be reasonably anticipated that ALX-0081 could be 
utilised, in combination with PE and transfusion, to directly inhibit the continuing formation of 
small thrombi and platelet consumption in the microvasculature. This may permit more rapid 
control of the underlying thrombotic process and accompanying platelet consumption, with 
the potential benefits of a reduced degree of ischaemic and haemorrhagic complications. It 
may also result in a more rapid clinical recovery with a shorter period and reduced number of 
PEs and transfusions. In addition, the demonstrated inhibition of ULvWF-mediated platelet 
interaction by ALX-0081 and the observed antithrombotic effects raise the potential for its 
longer-term use after patients have recovered from an acute bout of TTP to prevent relapses 
of the disease. A reduced frequency of acute bouts of TTP would represent a significant 
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benefit, with a potential for a reduction in the mortality and morbidity associated with TTP and 
a further reduction in the need for PE and transfusions over a patient’s lifetime.  
 
Potential benefit of ALX-0081 in TTP: quantification of major contribution to patient 
care 
For acquired TTP, the hypothesis of the proposed Phase II trial is to demonstrate a decrease 
of 44% in the time-to-response, objectivated by a recovery of platelets ≥ 150,000/µL. Platelet 
count increase is a sign of diminished pathological platelet aggregation, as well as a better 
protection against bleeding. The decrease of LDH is a sign of decreased haemolysis and/or 
tissue ischaemia. This response must be confirmed up to 48 hours after the time-to-
response. 
 
Potential benefit of ALX-0081 in TTP: safety 
While a more rapid recovery from TTP and a potential for a reduction in exacerbations and 
relapses would be of clear clinical benefit in terms of treatment efficacy, the potential for a 
reduction in the duration and frequency of PE and transfusion would also provide additional 
benefits in terms of patient safety. 
Although PE and transfusion are currently regarded as the standard treatment in the 
management of TTP, the procedures carry the risk of significant complications. The PE 
procedure requires high fluid volumes and flow rates necessitating the use of central venous 
dual lumen haemodialysis catheters. Complications from the procedure include haemorrhage 
from catheter insertion, sepsis, catheter thrombosis, pneumothorax, fluid overload, hypoxia 
and hypotension.18-22 Anaphylactoid reactions complicate 0.25% to 0.5% of procedures.13,19 
In addition, the infusion of plasma containing blood products can cause a non-infective 
TRALI. This condition is recognised as one of the most frequent causes of transfusion-
related fatalities with an incidence estimated to be 0.02% to 0.05% per plasma containing 
unit18 with a daily average of 17 plasma units, the daily risk can be calculated to a range of 
0.34% to 0.85%. Most patients with TTP require multiple PEs and transfusions. Patients with 
acute idiopathic TTP require daily treatments, and an average of approximately 16 
treatments is required to achieve remission.13 In refractory cases the frequency of treatment 
may be increased to twice-daily.13 In the case of patients with familial TTP, regular 
prophylactic plasma infusions at two to three week intervals are recommended.23 
Anaphylaxis and TRALI thus represent clear risks to patients with TTP whose treatment 
requires such a frequency and regularity of PEs and transfusions. While it is thought that this 
risk may be lower if solvent/detergent (S/D) treated plasma is used instead of fresh frozen 
plasma, the use of large volumes of S/D plasma may be associated with an increased risk of 
venous thromboembolism.13,18 Overall, it is estimated that approximately 30% to 40% 
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of patients will experience adverse effects from PE and transfusion, and the mortality rate 
from the procedure is of the order of 2% to 3%.2,19  
As summarised above, the information currently available from the preclinical and clinical 
studies with ALX-0081 also indicates that it is a well tolerated agent and, in particular, the 
potential for the risk of bleeding appears to be low. The currently available data suggest, 
therefore, that the potential reduction in PE and transfusion and their associated 
complications may be achieved without significant adverse effects from the use of ALX-0081 
itself. If this is borne out in clinical research, it could represent a clear safety benefit for the 
use of the product in the treatment of patients with TTP. 
 
Potential benefit of ALX-0081 in TTP: quality of life 
Following recovery from a bout of TTP, many patients describe cognitive abnormalities for 
many years and report troublesome problems with memory, concentration, decreased 
energy and fatigue. Such symptoms have a negative impact on the quality of patients’ daily 
lives. Furthermore, this deficit in quality of life may occur in all patients who have TTP, 
regardless of the aetiology and severity.24 It is thought that these symptoms may be reflective 
of the residual effects of tissue ischaemia. On this basis, it could be reasonably proposed 
that the potential for a more rapid recovery from TTP and the limitation of thrombus formation 
in the microvasculature that ALX-0081 should provide, may result in an improved longer-term 
outcome for the patients in terms of their quality of life.  
 
Summary 
The research conducted into TTP over the past three decades has improved the 
understanding of the pathophysiology of the disease allowing for the potential development 
of novel agents targeting the underlying disease processes. There are no currently approved 
therapies for TTP, and although there are newer therapies currently undergoing evaluation, 
the studies of these potential treatments are at a relatively early stage. 
ALX-0081 represents a novel approach to the treatment of TTP and the information available 
from in vitro, in vivo and early clinical studies all suggest a clear rationale for its use in this 
disease and a reasonable expectation that it will provide significant benefit in terms of 
efficacy, safety and quality of life for patients with TTP. 
Through its inhibition of ULvWF-mediated platelet aggregation and resulting antithrombotic 
effect ALX-0081 may permit more rapid control of acute bouts of TTP when used in 
combination with PE and transfusion. This would potentially reduce the risk of organ 
ischaemia and a more rapid normalisation of the platelet count could also reduce the risk of 
haemorrhagic complications. Its use may also result in improved outcomes in poorly 
responsive patients, including those with secondary TTP where mortality from the disease 
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remains high. In addition, ALX-0081 may be of value in the prevention of relapses after 
recovery from an acute episode. 
 
2.6 
Rationale for Dose Selection 
 
The initial i.v. administration of investigational drug prior to the first PE on study is justified 
based upon a Phase I study in healthy volunteers as well as a Phase Ib trial in ACS patients. 
In both studies, an immediate PD effect was observed, namely RIPA ≤ 10% in healthy 
volunteers and RICO ≤ 20% in ACS patients (see section 2.4). It is believed that all active 
ULvWF present in the blood that has not yet aggregated platelets can be inhibited from 
further platelet aggregation by saturating it with the immediate i.v. injection of 10 mg anti-vWF 
Nanobody. This would allow for predicted protection by the investigational product against 
further platelet aggregation until the time of start of PE therapy.  
The further administrations of the investigational drug will be performed by the s.c. injection 
route. The proposed s.c. dosing regimen of the ALX-0081 was investigated in a Phase I study 
with healthy volunteers. The daily dosing of ALX-0081 10 mg as s.c. injection resulted in a 
complete and sustainable inhibition of the biomarker RICO indicating the complete 
suppression of vWF-mediated platelet aggregation. PK modeling of these subjects with 
normal vWF pre-treatment levels demonstrated that the required occupancy of the target 
vWF resulting in maximum PD effect (i.e. RICO ≤ 20%) is seen for a wide range of ALX-0081 
plasma concentrations, i.e. between 100-500 ng/mL for 7 treatment days and between 100-
350 ng/mL for 14 treatment days. This implies that the maximum pharmacological effect can 
already be achieved at relative low plasma levels of ALX-0081. Taking into consideration that 
vWF plasma concentrations in patients with signs and symptoms of TTP can be considerably 
higher than in healthy volunteers, these data suggest that the proposed doses allow for full 
target occupancy and subsequent complete inhibition of the biomarker in patients with vWF 
levels within the range of 1 to 3 fold above the previously studied levels in healthy subjects 
and patients suffering from ACS. This range of target occupancy (i.e. saturation of plasma 
vWF) lies within the reported levels of plasma vWF for patients undergoing PE as treatment 
for TTP. 25,26 
 
The dosing scheme allows for a study drug treatment interruption based on clinically 
significant adverse drug reaction (i.e. bleeding events). 
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3. 
OBJECTIVES 
 
Primary  
• 
Reduction of time-to-response, defined by the achievement of laboratory blood 
marker response, confirmed at 48 hours after the initial reporting of this response 
 
Secondary (including longer-term disease sequelae)  
• 
Improvement in number of subjects responding to therapy 
• 
Reduction in PE procedure-related items  
• 
Reduction of time to resolution or improvement of symptoms typical of TTP, including 
blood markers 
• 
Reduction of number of exacerbations (defined as recurrent thrombocytopenia 
following a response and requiring a re-initiation of daily PE treatment after ≥ 1 day 
but ≤ 30 days after the last daily PE) and relapses (defined as de novo event of TTP 
that occurs later than 30 days after the last daily PE) 
• 
Improvement of cognitive level at steady state post acute phase 
• 
Improvement of clinical symptoms and organ function  
• 
Reduction in mortality within the PE treatment period and within the subsequent study 
drug treatment period (including tapering) 
• 
Reduction of concomitant treatment-related complications 
• 
Evaluation of safety and immunogenicity of adjunctive treatment with ALX-0081 
• 
Determination of PK and PD characteristics of ALX-0081 in patients with acquired 
TTP 
 
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4. 
TRIAL DESIGN 
 
4.1 
Study Endpoints 
 
4.1.1 
Primary Endpoint 
 
• 
Time-to-response, based on the following criteria:  
− 
Recovery of platelets ≥ 150,000/µL 
− 
This response must be confirmed at 48 hours after the initial reporting of 
platelet recovery equal to or above 150,000/µL by a de novo measure of 
platelets ≥ 150,000/µL and LDH ≤ 2 X ULN (i.e. “confirmed platelet response”) 
 
4.1.2 
Secondary Endpoints 
 
All endpoints achieved within 30 day period after end of study drug treatment: 
• 
Number of subjects with complete remission (defined as confirmed platelet response 
and absence of exacerbation) 
• 
Number 
of (subjects 
with) 
exacerbations 
of TTP 
(defined as 
recurrent 
thrombocytopenia following a confirmed platelet response and requiring a re-initiation 
of daily PE treatment after ≥ 1 day but ≤ 30 days after the last daily PE) and time to 
first exacerbation of TTP 
• 
Number of subjects relapsing of TTP (defined as de novo event of TTP that occurs 
later than 30 days after the last daily PE) 
• 
Number of daily PE sessions, number of plasma units administered and number of 
days of daily PE 
• 
Resolution of non-focal neurological symptoms as defined by neurocognitive function 
at complete remission, measured by a neurocognitive test battery 
• 
Resolution or improvement (improvement of ≥ 1 grade in the CTCAE v4.0 scale) of 
TTP-related signs and symptoms as captured on physical examination and as 
adverse events, at complete remission and at end of the study drug treatment period 
(including tapering) (by number of unique subjects and by total number of AEs) 
• 
Total mortality within the PE treatment period and within the subsequent study drug 
treatment period (including tapering) 
• 
Incidence of PE treatment-related AEs, such as, but not restricted to: haemorrhage 
from catheter insertion, sepsis, catheter thrombosis, pneumothorax, fluid overload, 
hypoxia, hypotension, anaphylactoid reactions and TRALI 
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• 
Incidence and severity of ALX-0081 treatment-emergent AEs and relationship to 
study drug 
• 
Development of ADA ≤ 30 days post-last study drug treatment 
• 
PK and PD profile 
 
4.1.3 
Tertiary Endpoints 
 
 
 
 
 
 
 
 
 
 
 
 
4.2 
Overall Study Design 
 
This is a Phase II multicentre, single-blinded, parallel design, randomised, placebo-controlled 
study. The study population is symptomatic patients with acute episodes of acquired TTP, 
requiring treatment with PE. After confirmation of eligibility to study participation, subjects will 
be randomised in a ratio of 1:1 to either receive ALX-0081 or placebo as adjunctive therapy 
to PE (Figure 4). Subjects will be randomised prior to the start of PE treatment. In 
exceptional cases however (due to need or ability to start PE in a time frame which does not 
allow all required screening and/or baseline study procedures to be performed), a subject 
may be randomised after the first, single PE session, but prior to the start of the second PE 
session. This overall second PE session should be started within 24 hours of the end of the 
very first PE session, and will be considered the first PE on study. 
 
The subjects will be followed in different phases during this study (also see Figure 5): 
• 
Screening and baseline measurements after admission to hospital 
• 
Treatment phase 
o Single i.v. bolus study drug administered via push injection 
o Daily PE adjunctive s.c. treatment phase 
o Post-daily PE s.c. treatment phase (including PE tapering if applicable, and 
study drug post-PE for 30 days after the very last PE) 
• 
Follow-up phase 
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Laboratory parameters for inclusion, study conduct, safety assessments and assessments of 
response/relapse, re-treatment and study medication dose modification will be assessed at 
each local site laboratory.  
 
 
Figure 4: 
Treatment flow chart. 
First PE on study: see section 4.2 
 
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4.3 
Overview of Treatment and Dosing Regimen for Study Drug 
 
The primary treatment for acquired TTP is daily PE. Immunosuppressive treatment is also 
often administered. The centres will follow their respective guidelines for the treatment of 
TTP patients, regarding all items other than the study drug. Discontinuation of daily PE 
depends on normalisation of platelet count, neurological status and other clinical and 
laboratory parameters. The frequency of PE is occasionally reduced (‘tapered’) rather than 
stopping completely at time of response, however this is not based on randomised clinical 
trial data and is not recommended per this protocol (although it is allowed if considered 
necessary by the Investigator). 
The study drug will be administered as adjunctive treatment at specific times relative to the 
PE procedures.  
The first administration is a single i.v. bolus injection, administered by a push injection. All 
subsequent administrations are s.c. injections. The study drug consists of 10 mg of 
ALX-0081 or placebo, once daily (except if PE is given twice daily, then study drug is 10 mg 
twice daily) as described in Section 7.2.  
 
Note that, in case of re-initiation of daily plasma exchange due to exacerbation, no i.v. bolus 
injection will be administered prior to the first new PE session; daily s.c. study drug 
administration will continue per protocol. 
 
4.4 
Study Duration 
 
The anticipated recruitment period is 30 months. The maximum total duration of individual 
study participation is a maximum of 15 months: a treatment phase of up to 90 days and a 
follow-up period of maximum of 1 year after remission or after 90 days of treatment, 
whichever comes first. Subjects will be hospitalised for at least 1 day after the last daily PE. 
 
4.5 
DSMB and Premature Termination of the Study 
 
4.5.1 
Data Safety Monitoring Board 
 
An independent DSMB will monitor accruing safety data during the study (SAEs on an 
ongoing basis and ‘early safety look’ when 16 subjects, 8 ALX-0081 treated and 8 placebo 
treated, have completed treatment with study drug) and will make recommendations on 
continuation of the study as appropriate. An interim analysis for safety with formal stopping 
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rules is foreseen when 28 of the ALX-0081 treated subjects have been treated, and will make 
a recommendation on study continuation or discontinuation. No formal review of efficacy data 
by the DSMB is foreseen.  
 
4.5.2 
Premature Termination of the Study 
 
The Sponsor in consultation with the DSMB and the CRO has the right to terminate the study 
prematurely for safety reasons. In addition, the Sponsor may terminate the study prematurely 
for administrative reasons at any time. In all cases all necessary measures have to be taken 
to guarantee appropriate safety follow-up of all subjects already included in the study. 
The Independent Ethics Committees (IEC) or Institutional Review Board (IRB) and the 
Regulatory Authorities will be informed in writing about any premature termination of the 
study. 
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5. 
SELECTION AND WITHDRAWAL OF SUBJECTS 
 
The target population for this trial includes symptomatic patients with acute episodes of 
acquired TTP, requiring treatment with PE. 
 
5.1 
Inclusion Criteria 
 
1. 18 years of age or older 
2. Men or women willing to accept an acceptable contraceptive regimen 
3. Patients with clinical diagnosis of TTP 
4. Necessitating PE (one, single PE session prior to randomisation into the study is 
allowed) 
5. Subject accessible to follow-up 
6. Obtained, signed and dated informed consent  
 
5.2 
Exclusion Criteria 
 
1. Platelet count greater or equal to 100,000/µL  
2. Severe active infection indicated by sepsis (requirement for pressors with or without 
positive blood cultures) 
3. Clinical evidence of enteric infection with E. coli 0157 or related organism 
4. Anti-phospholipid syndrome 
5. Diagnosis of DIC  
6. Pregnancy or breast-feeding 
7. Haematopoietic stem cell or bone marrow transplantation-associated thrombotic 
microangiopathy 
8. Known congenital TTP  
9. Active bleeding or high risk of bleeding 
10. Uncontrolled arterial hypertension 
11. Known chronic treatment with anticoagulant treatment that can not be stopped safely, 
including but not limited to: 
• 
vitamin K antagonists 
• 
heparin or LMWH 
• 
non-acetyl salicylic acid non-steroidal anti-inflammatory molecules 
12. Severe or life threatening clinical condition other than TTP that would impair 
participation in the trial 
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13. Subjects with malignancies resulting in a life expectation of less than 3 months  
14. Subjects with known or suspected bone marrow carcinosis 
15. Subjects who cannot comply with study protocol requirements and procedures.  
16. Known hypersensitivity to the active substance or to excipients of the study drug 
17. Severe liver impairment, corresponding to grade 3 toxicity defined by the CTCAE 
scale. For the key liver parameters, this is defined as follows: 
• 
bilirubin > 3 x ULN (need to differentiate isolated increase in indirect bilirubin 
due to haemolysis, this is not an exclusion parameter but disease related) 
• 
ALT/AST > 5 x ULN 
• 
AP > 5 x ULN 
• 
gamma glutamyl transpeptidase (GGT) > 5 x ULN 
18. Severe chronic renal impairment, as defined by GFR < 30 mL/min 
 
5.3 
Participation in concurrent clinical trials 
 
The use of another investigational drug or device within 30 days prior to screening is not 
allowed. Participation in non-interventional/observational studies and registries during the 
study period is allowed. Participation in another clinical trial is not allowed until the end of the 
follow up period or within 30 days after the last study treatment in case of early subject 
withdrawal from the study. Subjects that already participated in the current study (ALX 0681-
2.1/10) and that have either completed the study per protocol or have discontinued 
prematurely, are not allowed to be re-included.  
 
5.4 
Withdrawal of Subjects from Study  
 
5.4.1 
Definitions 
 
A 'completed' subject is one who has completed all phases of the study, including all follow-
up visits specified. 
A ‘withdrawal’ is a subject who stops prematurely for reasons related to the study, e.g. an 
AE. A subject who simply wishes to withdraw from the study should also be considered a 
withdrawal. 
 
 
 
 
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5.4.2 
Subject Discontinuation or Withdrawal 
 
Subjects are free to withdraw from participation in this study at any time, for any reason, 
specified or unspecified and without penalty or loss of benefits to which the subject is 
otherwise entitled. 
Subjects may be withdrawn from the study by the Investigator at any time due to an AE or 
any other reason if it is the opinion of the Investigator that continued participation in the study 
is no longer in the best interest of the subject. These reasons include, but are not limited to 
the following: 
• 
Adverse drug reaction or AE or any other reason for which, in the opinion of the 
Investigator, subject’s continued participation in the study is not in the best interest of 
the subject 
• 
Withdrawal of consent (subject must be withdrawn) 
• 
Subject fails to return to the site and does not respond to the attempts of the 
investigational site to contact him (lost to follow-up) 
• 
Protocol violation(s), such as non-compliance with study medication or visit schedule 
or treatment with prohibited concomitant medications 
• 
Pregnancy (treatment with study drug, if during treatment phase, must be 
discontinued and subject must be withdrawn from the study) 
 
Relapse of TTP on study (defined as de novo event of TTP that occurs later than 30 days 
after the last daily PE) is not considered a reason for study withdrawal. However re-initiation 
of study drug treatment as an adjunctive treatment to PE in case of TTP relapse is not 
permitted. 
 
Subjects discontinuing study drug administration should be encouraged to remain in the 
study and complete the originally scheduled follow-up visits.  
 
For all subjects withdrawing from the trial for whatever reason, all data will be collected, 
documented and reported. The case report form (CRF) must be completed up to the time of 
withdrawal and the Premature Termination Form must be completed. Except for subjects 
who refuse to return to the investigational site, all subjects withdrawn after at least one 
administration of study drug should undergo a post-study assessment. 
 
In case of withdrawal from the study due to an AE, subjects should be followed by the 
Investigator until the AE has resolved. 
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5.4.3 
Procedure for Handling Withdrawals and Replacements 
 
All cases of premature termination, or exclusion of individual subjects, will be discussed with 
the Sponsor and it will be decided in consultation with the Sponsor whether this subject will 
need to be replaced. Subjects withdrawn due to adverse drug reactions or adverse events 
will not be replaced. 
If a withdrawal has to be replaced the replacement subject will undergo the same procedures 
and assessments as ‘new’ subjects. 
If a subject withdraws before allocation of a subject number: 
• 
The replacement will be regarded as a ‘new’ subject and therapy allocated 
accordingly. 
If a subject withdraws after allocation of a subject number: 
• 
The replacement will be allocated to the same randomisation as the subject to be 
replaced, but will be allocated a new subject number.  
 
The new (replacement) number is attributed by the statistician responsible for 
 
randomisation and the corresponding medication shipped to the site. 
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6. 
STUDY DRUGS 
 
Study drugs include the anti-vWF Nanobody (ALX-0081) and the matching placebo 
administered during the course of the study. 
 
6.1 
Formulation, Packaging and Labelling 
 
6.1.1 
Study Drug Formulation 
 
ALX-0081, anti-vWF Nanobody  
ALX-0081 is a clear, colourless solution formulated as a solution for injection. It is provided in 
sterile, preservative-free, non-pyrogenic, single-use 2R glass vials with injection stoppers 
and light blue aluminum crimped caps. One vial contains 2.4 mL solution for injection. One 
mL solution for injection contains as active ingredient 5 mg of ALX-0081 (INN: 
caplacizumab). 
 
Excipients 
Phosphate buffer solution (pH 7.1):  
WFI, KCl, KH2PO4, Na2HPO4x2H2O and NaCl. Glycine (0.2 M) and polysorbate 80 (0.02%) 
are used to stabilise the protein in the solution.  
 
Placebo 
Placebo is provided in 2R glass vials. One vial contains 2.4 mL solution for injection with 
identical excipients as ALX-0081. 
 
6.1.2 
Study Drug Packaging  
 
Ablynx NV will, via a contract manufacturer, supply the following medication: 
• 
Vials containing 2.4 mL solution of 5 mg/mL of ALX-0081 
• 
Matching placebo vials 
The study medication will be packed and dispatched in containers. The batch number and 
the minimal shelf-life will be given on the outer package. A batch release certificate and a 
GMP-conformity statement will be provided. Study drugs are provided as vials for injection 
and supplied to the study centre. 
 
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6.1.3 
Study Drug Labelling 
 
The study drug will be labelled in accordance with applicable regulatory requirements. At the 
minimum, the following information will be provided: 
• 
Study number (ALX-0681-2.1/10) 
• 
Name and address of Sponsor 
• 
Batch number and vial number 
• 
Volume 
• 
Pharmaceutical form and route of administration (respectively i.v. or s.c.) 
• 
Storage conditions 
• 
Retest or expiry date 
• 
“For clinical trial use only” and “Keep out of reach and sight of children” 
 
6.2 
Storage and Stability 
 
ALX-0081 and placebo are delivered and stored deep frozen at –20°C (± 5°C) in the original 
outer package to be protected from light. Stability studies showed that ALX-0081 is stable at 
-20°C for at least 3 years and can therefore be stored under these conditions at the 
investigative site. ALX-0081 contains no antimicrobial preservatives. The study drug must not 
be used after the expiry date indicated on the labels of the outer package. 
Upon receipt of the study medication, the responsible pharmacist or his/her designee will 
inspect and count all study medication for completeness. Subsequently, he/she must 
immediately return the enclosed acknowledgement of receipt form, duly completed and 
signed (the date of receipt must be noted). 
The pharmacist or his/her designee is responsible for storage of the study medication at the 
study site in an appropriate lockable room at –20°C (± 5°C). The medication may not be 
exposed to direct sunlight or to direct warmth given off by heaters and should be protected 
from moisture.  
 
6.3 
Study Drug Preparation and Administration 
 
All study medications will be prepared at the investigational site by a pharmacist or his/her 
designee.  
 
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Study drug preparation and administration during hospitalisation 
During hospitalisation, all study medications will be administered by the Investigator or by 
medically trained personnel under his/her supervision.  
ALX-0081 solution for injection is for single use only. Remaining ALX-0081 solution for 
injection should be discarded. Procedures for proper handling and disposal should be 
observed. 
 
Study drug preparation for dispension to subjects, and administration thereafter 
Vials will be thawed in a 25°C water bath or at room temperature until all ice has visibly 
disappeared and inspected prior to dispension to subjects. Transport of study medication 
from the hospital to the subject’s home should be secured between 2-8°C. The subject 
should be instructed to keep the study medication cooled within a refrigerator (2-8°C) until 
use. Injections must be prepared and administered by medically trained personnel. 
Vials can be used during 10 days after thawing. All thawed vials and unused injections 
should be returned to the pharmacy on a weekly basis. Note that returned vials can no longer 
be used for administration. 
 
For detailed instructions on the preparation of the solution for injection, its administration and 
disposal please refer to the IB. 
 
6.4 
Return of Study Drug 
 
Generally, all unused study drug (medication and packaging) must be returned to the 
Sponsor on termination of the study and after a drug accountability and reconciliation check. 
Upon permission/request of the Sponsor, and if allowed by local procedures and regulations, 
unused study drug may be destroyed on site. The destruction has to be clearly documented, 
and can only occur after drug accountability and reconciliation check. 
 
Used study medication can be destroyed per institution policy after drug accountability has 
been checked. 
 
The pharmacist or his/her designee will be responsible for the inventory of all clinical 
supplies, exercising accepted pharmaceutical practices. An accurate, timely record of the 
clinical study supply will be maintained. The original Drug Preparation Log and Drug 
Dispensing and Accountability Log are considered as source data and will be archived at the 
site. 
 
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6.5 
Drug Accountability 
 
Supplies of ALX-0081 will be shipped deep frozen at -20°C (± 5°C) to the hospital at 
appropriate intervals, depending on subject accrual. The Investigator at the study site is 
responsible for keeping accurate drug accountability records throughout the study regarding 
the receipt of study drug, the dispensing to the subjects and the return of all used and 
unused study drug.  
A Drug Preparation Log as well as a Drug Dispensing and Accountability and temperature 
Log must be kept current and should contain the following information: 
 
• 
In hospital use: 
o Vial number 
o Subject number for whom the drug was prepared 
o Number of injections prepared 
o Date on which drug was dispensed 
o Quantity of the drug administered 
 
• 
Use at home by the subject: 
o Subject number to whom the drug was dispensed 
o Information on vials dispensed  
 
Number of vials dispensed 
 
Vial identification numbers dispensed 
 
Date of thawing 
 
Date of dispension 
 
Vials returned by the subject 
o Name of the person who administered the study drug 
o Date and time of study drug administration 
o Quantity of the drug administered 
 
The inventory must be available for inspection by the monitor. 
Generally, at study termination, all unused study medication must be returned to the Sponsor 
accompanied by the appropriate documentation. Upon permission/request of the Sponsor, 
and if allowed by local procedures and regulations, unused study drug may be destroyed on 
site. The destruction has to be clearly documented, and can only occur after drug 
accountability and reconciliation check. Used study medication can be destroyed per 
institution policy after drug accountability has been checked. 
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7. 
TREATMENT 
 
7.1 
Treatments to be Administered 
  
Subjects will receive best medical care and treatment judged appropriate by the Investigator 
at each site and according to site guidelines for treatment of TTP. The principal treatment for 
acquired TTP is daily PE. Discontinuation of daily PE depends on normalisation of platelet 
count, neurological status and other clinical and laboratory parameters. The frequency of PE 
is occasionally reduced (‘tapered’) rather than stopping completely at time of response, 
however this is not based on randomised clinical trial data and is not recommended per this 
protocol (although it is allowed if considered necessary by the Investigator). 
Additional 
treatment 
may 
include 
one 
or 
more 
of 
the 
following: 
adjunctive 
immunosuppressive treatment (e.g. corticosteroids, rituximab), antiplatelet agents (e.g. 
aspirin), supportive therapy with red cell transfusion or folate supplementation, treatment with 
vincristine or cyclosporin in case of refractory TTP.13 After platelet counts have partially 
recovered, LMWH may be used prophylactically in patients at high risk for venous 
thromboembolism. In this case heparin will be administered according to local institutional 
guidelines, or in the absence of these, after a platelet count of at least 100,000/μL has been 
reached.  
 
7.2 
Treatment and Dosing Regimen for Study Drug 
 
The study drug will be administered as adjunctive treatment at specific times relative to the 
PE procedures. The study drug consists of 10 mg of ALX-0081 or placebo, once or twice 
daily as explained below (Table 8).  
 
Subjects will receive a first i.v. bolus of 10 mg ALX-0081 or placebo via push injection within 
6h, but not later than 15 min prior to the initiation of PE on study (i.e., the very first PE 
session, if the subject was randomised prior to the initiation of PE, or the second PE session, 
if the subject was randomised after one, single PE session; see section 4.2). This first PE on 
study is followed by s.c. administration of 10 mg study drug within 30 minutes after the end of 
the PE procedure. 
 
During the complete PE treatment period (including tapering and PE given for 
exacerbations), study drug will be administered daily via s.c. injections. 
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• 
If 1 PE per day is scheduled, 10 mg of study drug will be administered within 30 
minutes after the end of the PE procedure. 
• 
If 2 PEs per day are scheduled, 10 mg of study drug will be administered within 30 
minutes after the end of each PE procedure. The maximum total daily dose of study 
drug is hence 20 mg. 
• 
If less than 1 PE per day is scheduled (i.e. during a tapering regimen), 10 mg of study 
drug will be administered daily. On days with a PE, study drug administration should 
be within 30 minutes after the end of the PE procedure; on days without PE, study 
drug administration should be 24 h (± 1 h) after previous administration 
 
Daily s.c. study drug administration of 10 mg will continue for 30 days after the very last PE 
(including tapering).  
 
Maximum treatment duration with study drug will be limited to 90 days after first 
administration of study drug. 
 
In case of exacerbation of TTP (after ≥ 1 day but ≤ 30 days after the last daily PE), standard 
treatment (PE) should be re-initiated and daily s.c. administration of study drug continued.a 
The “study drug post-PE” period (for 30 days after the very last PE, see Figure 5 further 
below) will re-commence once PE is again stopped. Maximum treatment duration with study 
drug will be limited to 90 days after first administration of study drug. 
 
Re-initiation of study drug treatment as an adjunctive treatment to PE in case of on-study 
TTP relapse is not permitted. Relapse of TTP is defined as de novo event of TTP that occurs 
later than 30 days after the last daily PE. Tapering will prolong study drug administration and 
delay the start of the “study drug post-PE” period (see Figure 5 further below). It is therefore 
possible that a relapse would occur ≥ 30 days after the last daily PE, but before the end of 
the 30-day period of study drug administration post-PE. In this case, the study drug is to be 
discontinued at the restart of the PE treatment.  
 
The s.c. injections will be performed on the abdomen according to a written instruction 
manual. At each administration, subjects will receive two s.c. injections of 1 mL ALX-0081 
solution for injection (5 mg/mL) or placebo solution at different abdominal locations. The site 
                                               
a  Note that, in case of re-initiation of daily PE due to exacerbation, no i.v. bolus injection has to be 
administered prior to the first new PE session; daily s.c. study drug administration will continue per 
protocol. 
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of the injections will be recorded and will be changed from day to day. The time of 
administration of study drug and the initials of the person performing the administration will 
be recorded in the source documents. All injections of study drug will be performed by 
medical or paramedical personnel. 
 
7.3 
Dose modification due to treatment related AE – clinically relevant 
bleeding 
 
Clinically relevant bleeding is the main potential risk based on the pharmacological action of 
ALX-0081. It is defined as moderate to severe (including life-threatening) bleeding requiring 
urgent medical and/or surgical intervention. In case of clinically relevant bleeding, 
appropriate treatment for bleeding according to standard practice should be initiated and 
treatment with study drug must be interrupted. In addition, plasma levels of vWF:Ag and FVIII 
chromogene should be determined. If FVIII < 10%, assess for anti-FVIII antibodies and if 
presence is confirmed, permanently discontinue study drug. If either or both vWF and FVIII 
are at clinically significant low levels, administration of vWF and FVIII through commercially 
available combination preparations, such as Haemate-P or equivalent antihaemophilic 
factor/vWF complex should be initiated and continued until the bleeding stops. Study drug 
should only be restarted when the bleeding has stopped and vWF > 50% and FVIII level is 
within normal range. The PE treatment, if applicable, should continue as clinically indicated. 
 
Dosage, method of administration and duration of treatment are summarised in Table 8. 
 
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Table 8: 
Dosage, method of administration and treatment duration. 
First study drug administration is 10 mg as an i.v. bolus, administered by a push injection, 15 
minutes to 6 hours prior to initiation of PE on study.* This first PE on study is followed by 
subcutaneous (s.c.) administration of 10 mg study drug. 
* As discussed in section 4.2, one PE session prior to randomisation is allowed. In such case, the second PE 
session will be the first PE on study. 
 
S.c. study drug administration during treatment phase with PE 
Frequency of PE 
Treatment administration - daily 
1 PE/day 
Administer 10 mg study drug within 30 min after end of PE 
2 PEs/day 
• For subjects receiving anti-vWF Nanobody: administer 10 mg study 
drug within 30 min after each PE  
• For subjects receiving placebo, maintain a once daily dosing regimen 
Tapering (< 1 PE/day) 
Daily administration of 10 mg study drug. On days with PE: within 30 min 
after end of PE; on days without PE at 24 h (± 1 h) after previous 
administration 
 
S.c. study drug administration (in hospital and at home) for 30 days after the very last PE (including 
tapering and PE given for exacerbations)*: 10 mg study drug once daily. 
*  As discussed in section 7.2, in case of exacerbation of TTP, standard treatment (PE) should be re-initiated and 
daily administration of study drug continued. The “study drug post-PE” period (for 30 days after the very last PE) 
will recommence once PE is again stopped. Maximum treatment duration with study drug will be limited to 90 
days after first administration of study drug. 
 
If clinically relevant bleeding* occurs 
• Stop study drug administration and continue PE if clinically indicated and applicable 
• Assess vWF:Ag and Factor VIII (FVIII) levels**. If FVIII < 10%, assess for anti-FVIII antibodies and 
if presence is confirmed, permanently discontinue study drug. 
• If vWF:Ag and/or FVIII levels are at a clinically significant low level, initiate i.v. Haemate-P 50 U/kg 
(or equivalent antihaemophilic factor/vWF complex) 
• i.v. Haemate-P treatment should be discontinued when bleeding has clearly stopped and when 
vWF > 50% 
• Restart study medication at 10 mg daily when bleeding has clearly stopped and when vWF > 50% 
and FVIII levels are within normal range 
*  Clinically relevant bleeding is defined as moderate to severe (including life-threatening) bleeding requiring 
urgent medical and/or surgical intervention.  
** FVIII chromogene or other measure of FVIII activity 
 
7.4 
Prior / Concomitant Medication 
 
Upon inclusion in the study, chronic treatment with anticoagulant treatment such as vitamin K 
antagonists, heparin (or LMWH) and non-acetyl salicylic acid non-steroidal anti-inflammatory 
molecules should be discontinued. If recommended by local guidelines, aspirin can be 
continued. Heparin can be administered according to local institutional guidelines, or in the 
absence of these, after a platelet count of at least 100,000/µL has been reached. Re-
initiation of anticoagulant treatment is allowed whenever required to ensure the safety of the 
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subject. (Re-)initiation of anticoagulant treatment should be guided upon balancing the risk 
for thrombosis versus the risk for bleeding and should be based upon local guidelines. For 
example, LMWH can be used prophylactically in subjects at high risk for venous 
thromboembolism whenever platelet counts have partially recovered. Anticoagulant 
treatment prescribed as part of the local PE procedure is allowed.  
Concomitant medication administered specifically as part of the PE procedure and during the 
course of the PE session will be recorded separately. Other concomitant and adjunctive 
medication, such as methylprednisone, rituximab and other immunosuppressives will be 
reported in the concomitant medication other than PE-related medication. 
Medication given in response to a PE-related AE (i.e. antibiotic administration due to a 
central line infection) will be reported in the concomitant medication other than PE-related 
medication.  
Any concomitant medication taken during the study must be recorded in the CRF. Items to 
be recorded concerning concomitant medication include: dose and units of dose, 
modification of dose, start time and date, end time and date, administration frequency, route 
of administration, therapeutic indication. 
Desmopressin should be considered as prohibited medication. 
 
7.5 
Assignment to Treatment 
 
Subjects will be assigned to one of the two treatments according to a computerised 
randomisation schedule. When the randomisation number and treatment assignment are 
obtained, the randomisation number will be recorded on the CRF. This is a single blinded 
study. The Investigator will be informed of the treatment at the time of randomisation. 
Randomisation is performed via an interactive web-based system.  
 
7.6 
Management of Overdose 
 
In case of suspected or actual overdose, there is an increased risk of bleeding based on the 
pharmacological action of study drug. Subjects should therefore be monitored closely for 
signs and symptoms of clinically relevant bleeding, defined as moderate to severe (including 
life-threatening) bleeding requiring urgent medical and/or surgical intervention (see Section 
7.3). In case of clinically relevant bleeding associated with (suspected) overdose, appropriate 
treatment for bleeding according to standard practice should be initiated and treatment with 
study drug must be interrupted. In addition, plasma levels of vWF:Ag and FVIII should be 
determined. If FVIII < 10%, assess for anti-FVIII antibodies and if presence is confirmed, 
permanently discontinue study drug. If either or both vWF and FVIII are at clinically 
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significant low levels, administration of vWF and FVIII through commercially available 
combination preparations, such as Haemate-P or equivalent antihaemophilic factor/vWF 
complex should be initiated and continued until the bleeding stops. Treatment with study 
drug should only be restarted when the bleeding has stopped and when vWF > 50% and 
FVIII levels are within normal range. The PE treatment, if applicable, should continue as 
clinically indicated. 
In case of (suspected) overdose with no clinically relevant bleeding observed, study drug 
administration may continue with the next PE or next daily dose as applicable and as per 
protocol.  
 
7.7 
Management of Hypersensitivity Reactions 
 
In the case of immediate or late allergic or immunogenic reaction to ALX-0081 - manifesting 
as itching, rash, hives, or in severe cases as anaphylactic reaction or even shock - 
appropriate standard medical care measurements will be initiated by the responsible 
Investigator involving the intensive care unit when necessary. 
 
7.8 
Restrictions  
 
Males who can father children and women of childbearing potential, must use double-barrier 
contraception during the study and during the first 3 months after last dosing. This is the use 
of a condom with spermicidal paste or the use of oral contraception combined with male 
condom or vaginal condom or other adequate combination of 2 contraceptive methods.  
Subjects should refrain from potentially dangerous activities or contact sports during the 
treatment phase of the study and until 7 days after last administration of study drug. 
 
7.9 
Treatment Compliance 
 
Records of study drug used, dosages administered and intervals between visits are kept 
during the study. Study drug accountability is performed on an ongoing basis by the study 
staff and checked by the monitor during site visits and at the completion of the study. 
The administration of the study medication will be performed by the Investigator or Sub-
Investigator or medically trained personnel and will be documented accordingly.  
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8. 
STUDY ASSESSMENTS AND PROCEDURES 
 
8.1 
Description of Study Days and Schedules of Assessments 
 
The subjects will be followed in different phases during this study: 
• 
Screening and baseline measurements after admission to hospital 
• 
Treatment phase 
o Single i.v. bolus study drug administered via push injection 
o Daily PE adjunctive s.c. treatment phase 
o Post-daily PE s.c. treatment phase (including PE tapering if applicable, and 
study drug post-PE for 30 days after the very last PE) 
• 
Follow-up phase 
 
Please see Figure 5 for a schematic overview of the different study phases. A general 
overview of study assessment is shown in Table 9. 
Time intervals and follow-up window details are provided in Table 10, Table 11 and Table 13. 
 
 
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Figure 5: 
Schematic overview of pre-treatment, treatment and follow-up phase. 
* Subjects will be randomised prior to the start of PE treatment. In exceptional cases however (due to need or ability to start PE in a time frame which does 
not allow all required screening and/or baseline study procedures to be performed), a subject may be randomised after the first, single PE session, but prior 
to the start of the second PE session. This overall second PE session should be started within 24 hours of the end of the very first PE session, and will be 
considered the first PE on study. 
 
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Table 9: 
General schedule of study assessments. 
 
Screening 
Baseline 
Treatment phase 
Follow-up 
AE and 
unsche-
duled visit 
Study drug i.v. bolus 
Daily PE 
treatment 
phase  
Day 1 after 
last daily PE 
Post daily PE 
(including PE 
tapering) 
30 day post last PE (including tapering)- stop study drug 
Day 3 Day 7 
1m 
2m 
3m 
6m 
12m 
Time interval 
≤12h prior to 
first PE on 
study and 
study drug 
15min-6h 
prior to first 
PE on study 
and study 
drug 
see Table 11 
1 day 
see Table 11 
±1d 
±1d 
±3d 
±7d 
±15d ±15d ±15d as needed 
Assessment/Activity 
 
 
Treatment with study drug 
 
 
X 
X 
X 
 
 
 
 
 
 
 
 
PK (central lab) 
 
X 
X 
X 
X 
X 
X 
X 
 
 
 
 
X 
RICO (central lab) 
 
X 
X 
X 
X 
X 
X 
X 
 
 
 
 
X 
ADA (central lab) 
 
X 
X 
X 
X 
 
 
X 
X 
X 
X 
X 
X 
vWF (central lab) 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
FVIII chromogene (central lab) 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Blood type (ABO and Rh) and direct antiglobulin 
test (DAT) (local lab) 
X 
 
 
 
 
 
 
 
 
 
 
 
 
Blood chemistry (local lab) 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Haematology (local lab) 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Coagulation (local lab) 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Urine pregnancy test (local lab) 
X 
 
 
 
 
 
 
X 
 
X 
 
 
 
Urinalysis (local lab) 
X 
 
 
 
 
 
 
 
 
 
 
 
 
HIV1/2, HBV, HCV (local lab) 
X 
 
 
 
 
 
 
 
 
 
 
 
 
Cardiac marker (TnT or TnI) (local lab) 
 
X 
X 
X 
X 
 
 
X 
 
 
 
X 
X 
BNP or NT proBNP (local lab) 
 
X 
X 
X 
X 
 
 
X 
 
 
 
X 
X 
Brain damage markers (NSE, Sβ100)  
(central lab)  
 
X 
X 
X 
X 
 
 
X 
 
 
 
X 
X 
ADAMTS13 & anti-ADAMTS13-antibodies  
(central lab) 
X 
 
 
X 
X 
 
 
X 
 
 
 
X 
X 
12-lead ECG 
 
X 
X 
X 
X 
 
 
X 
X 
X 
X 
X 
X 
Informed consent 
X 
 
 
 
 
 
 
 
 
 
 
 
 
Inclusion/exclusion criteria 
X 
 
 
 
 
 
 
 
 
 
 
 
 
Medical history and demographics 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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Screening 
Baseline 
Treatment phase 
Follow-up 
AE and 
unsche-
duled visit 
 
Daily PE 
treatment 
phase  
Day 1 after 
last daily PE 
Post daily PE 
(including PE 
tapering) 
 
Day 3 Day 7 
1m 
2m 
3m 
6m 
12m 
Time interval 
≤12h prior to 
first PE on 
study and 
study drug 
15min-6h 
prior to first 
PE on study 
and study 
drug 
see Table 11 
1 day 
see Table 11 
±1d 
±1d 
±3d 
±7d 
±15d ±15d ±15d as needed 
Physical examination and vital signs 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Spent plasma retrieval 
 
 
X 
 
 
 
 
 
 
 
 
 
 
Modified ITP bleeding score 
 
X 
X 
X 
X 
 
 
X 
 
 
 
 
X 
Clinically relevant bleeding 
X 
X 
X 
X 
X 
 
 
X 
 
 
 
 
X 
Glasgow Coma Score 
X 
Xc 
X 
X 
X 
 
 
 
 
 
 
 
 
Neurocognitive battery 
 
X 
X 
 
 
X 
 
 
 
 
 
X 
 
Recuperate nurse sheet and/ or AE diary 
 
 
 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
PE detailsa 
 
 
Xa 
Xa 
Xa 
 
 
 
 
 
 
 
 
Prior/concomitant medication recording other 
than PE related treatmentb 
Xb 
Xb 
Xb 
Xb 
Xb 
Xb 
Xb 
Xb 
Xb 
Xb 
Xb 
Xb 
Xb 
AE recording 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
First PE on study: see section 4.2. 
a Including RBC transfusion details 
b Including concomitant medication related and simultaneous to PE. 
c If abnormal at screening 
 
 
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8.1.1 
Screening and Baseline Measurements 
 
In a window of time defined by less than 12 hours prior to initiation of first PE on study (as 
detailed in section 4.2) and study drug, all subjects will undergo a thorough examination to 
investigate their suitability for participation in the study. Inclusion and exclusion criteria will be 
checked. A screening log should be maintained, recording the reason when subjects are 
screened but not included in the study. If the subject satisfies the inclusion and exclusion 
criteria, informed consent will be obtained prior to randomisation and additional assessments 
will be performed within 15 minutes to 6 hours prior to initiation of the first PE on study and 
study drug. If done within 6 hours of starting study drug, the chemistry, haematology and 
coagulation assessments can be considered baseline and do not need to be repeated (see 
Table 10).  
 
The following screening procedures must be performed prior to randomisation (see Table 
10): 
• 
Check in/exclusion criteria 
• 
Demographic data (e.g. age, height, weight, body mass index (BMI), ethnic origin and 
number of years of formal education completed). The balance should have a 
precision of at least 0.5 kg. Body weight will be recorded in kg with 1 decimal. The 
BMI will be calculated from the weight and height: BMI (kg/m2) = weight (kg) / height 
(m) x height (m).  
• 
Medical history 
• 
Prior and concomitant medication taken during the 30 days prior to the screening 
examination are to be documented. Concomitant medication from the 30 days prior to 
screening until follow-up or started during the course of the study will be recorded on 
the Concomitant Medications page of the CRF. Concomitant medications initiated, 
stopped, up-titrated or down-titrated for an AE will also be recorded on a specific 
Concomitant Medications page of the CRF. 
• 
Clinical assessment will include physical examination and vital signs (blood pressure 
and heart rate at rest, body temperature), 
• 
Obtain signed and dated informed consent 
• 
The Glasgow Coma Score will be determined using the Glasgow Coma Scale 
(original scale), which is a neurological scale that measures the conscious state of 
the subject. The best eye, verbal and motor responses will be scored according to the 
scale and the separate scores added up to obtain the final score, ranging from 3 to 
15. 
• 
Assessment of clinically relevant bleeding 
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• 
Urinalysis (local laboratory) 
• 
Urine pregnancy test for female subjects (Human chorionic gonadotropin (hCG) only) 
(local laboratory) 
• 
Blood typing (ABO, Rh) and direct antiglobulin test (DAT) (local laboratory) 
• 
Blood sampling for chemistry will include the following: glucose, bilirubin (total), AP, 
AST, ALT, LDH, C-reactive protein (CRP), hCG (for women, only if urine pregnancy 
test not feasible or inconclusive), haptoglobin, rheumatoid factor, antinucleic acid, 
iron, ferritin, transferrin, creatinine, urea (blood urea nitrogen (BUN)), uric acid, 
protein, albumin, sodium (Na), potassium (K), calcium (Ca), magnesium (Mg) and 
chloride (Cl) (local laboratory) 
• 
Blood sampling for haematology will include the following: haemoglobin, haematocrit, 
mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean 
corpuscular haemoglobin concentration (MCHC), full blood count including red blood 
cells (RBC), white blood cells (WBC), differential, reticulocytes, optical platelet count 
and immature platelet fraction (local laboratory). In case optical platelet counts are 
not available, they can be replaced by measurements based upon impedance. If not 
available in the local laboratory, immature platelet fraction measurements can be 
omitted 
• 
Blood sampling for coagulation variables will include: fibrinogen, aPTT, PT, 
international normalised ratio (INR), vWF:Ag, FVIII chromogene, lupus anticoagulant, 
anticardiolipin antibodies (antiphospholipid) (local laboratory). In case FVIII 
chromogene is not available in the local laboratory, it can be replaced by an 
alternative method (e.g. one stage clotting assay) 
• 
Blood sampling for viral serology (hepatitis B virus (HBV), hepatitis C virus (HCV), 
HIV subtype-1 and -2 [HIV-1 and HIV-2]) (local laboratory) 
• 
Blood sampling for ADAMTS13 and anti-ADAMTS13 antibody titre (central 
laboratory). 
 
The following procedures must be performed after randomisation, as baseline assessments 
(see Table 10): 
• 
Prior and concomitant medication taken during the 30 days prior to the screening 
examination are to be documented. Concomitant medication from the 30 days prior to 
screening until follow-up or started during the course of the study will be recorded on 
the Concomitant Medications page of the CRF. Concomitant medications initiated, 
stopped, up-titrated or down-titrated for an AE will also be recorded on a specific 
Concomitant Medications page of the CRF. 
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• 
Clinical assessment will include physical examination and vital signs (blood pressure 
and heart rate at rest, body temperature), 
• 
AE recording 
• 
Glasgow Coma Score (if abnormal at screening) 
• 
The neurocognitive battery, only if level of consciousness and attentiveness of the 
subject permits and environmental factors are appropriate to support neurocognitive 
testing (e.g., subject is able to sit upright and interact with computer touch screen; 
subjects have eyeglasses used for reading and hearing devices, if applicable; testing 
area is quiet and relatively free of distracting stimuli) 
• 
Bleeding score according to the modified ITP bleeding score 
• 
Assessment of clinically relevant bleeding 
• 
12-lead ECG  
• 
Blood sampling for chemistry (local laboratory) (only if sampling for screening was 
done more than 6 h prior to first PE on study and first study drug administration)b 
• 
Blood sampling for haematology (local laboratory) (only if sampling for screening was 
done more than 6 h prior to first PE on study and first study drug administration)b  
• 
Blood sampling for coagulation variables (local laboratory) (only if sampling for 
screening was done more than 6 h prior to first PE on study and first study drug 
administration)b 
• 
Blood sampling for markers for cardiac cell death: Troponin T (local laboratory). In 
case Troponin T is not available in the local laboratory, it can be replaced by 
Troponin I 
• 
Blood sampling for markers for heart failure: BNP (brain natriuretic peptide) or N-
terminal pro brain natriuretic peptide (NT-proBNP) (local laboratory) 
• 
Blood sampling for markers for brain damage: NSE (neuron specific enolase), protein 
S100 beta (Sβ100) (central laboratory) 
• 
Blood sampling for PK (central laboratory). This sample needs to be drawn within 
1 hour prior to the first administration of study drug 
• 
Blood sampling for PD assessments. This sample needs to be drawn within 1 hour 
prior to the first administration of study drug. The PD assessments include RICO, 
vWF (vWF:Ag and vWF propeptide) and FVIII chromogene (central laboratory). 
• 
Blood sampling for ADA (central laboratory). This sample needs to be drawn within 
1 hour prior to the first administration of study drug 
 
                                               
b Not to be repeated if screening assessment occurred within 6 hours of starting study drug. 
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The procedures to be performed at screening and/or baseline are also listed in Table 10. 
 
Table 10: 
Schedule of assessments at screening and baseline measurements.  
Assessment/Activity 
Screening 
less than 12 h 
prior to first 
PE on study 
Baseline 
less than 6 h 
prior to first 
PE on study 
Informed consent 
X 
 
In/exclusion criteria 
X 
 
Medical history and demographic data 
X 
 
Blood typing (ABO and Rh) and DAT (local lab) 
X 
 
Physical examination and vital signs 
X 
X 
Serology (HIV1/2, HBV and HCV) (local lab) 
X 
 
Urinalysis (local lab) 
X 
 
Urine or blood pregnancy test for female subjects (hCG only) (local 
lab) 
X 
 
12-lead ECG 
 
X 
Blood chemistry (local lab)a 
X 
Xa 
Haematology (local lab)a 
X 
Xa 
Coagulation variables (local lab)a 
X 
Xa 
Prior and concomitant medication other than PE related treatment 
X 
X 
ADAMTS13 and anti-ADAMTS13 antibody titre (central lab) 
X 
 
PK (central lab)b 
 
Xb 
RICO (central lab)b 
 
Xb 
vWF (central lab)b 
 
Xb 
FVIII chromogene (central lab)b 
 
Xb 
ADA (central lab)b 
 
Xb 
Cardiac marker (TnT or TnI) (local lab) 
 
X 
BNP or NT proBNP (local lab) 
 
X 
Brain damage markers (NSE, Sβ100) (central laboratory) 
 
X 
Modified ITP bleeding score 
 
X 
Clinically relevant bleeding 
X 
X 
Glasgow Coma Scorec 
X 
Xc 
Neurocognitive batteryd 
 
Xd 
AE recording 
 
X 
First PE on study: see section 4.2. 
a values determined at screening can be used as baseline values to avoid additional blood sampling, if screening 
assessment occurred within 6 hours of starting study drug. 
b ≤ 1h prior to first study drug administration 
c if abnormal at screening 
d if possible 
 
Blood chemistry includes glucose, bilirubin (total), AP, AST, ALT, LDH, CRP, hCG (for women, to be performed 
as soon as possible, if urine pregnancy test is not feasible or inconclusive), haptoglobin, rheumatoid factor, 
antinucleic acid, iron, ferritin, transferrin, creatinine, urea (BUN), uric acid, protein, albumin, Na, K, Ca, Mg and Cl. 
Haematology includes haemoglobin, haematocrit, MCV, MCH, MCHC, full blood count including RBC, WBC, 
differential, reticulocytes, platelet count and, if available, immature platelet fraction. 
Coagulation variables include fibrinogen, aPTT, PT, INR, vWF:Ag, FVIII (chromogene or alternative method), 
lupus anticoagulant, anticardiolipin antibodies (antiphospholipid). 
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8.1.2 
Treatment Phase 
 
The treatment phase commences with the first study drug administration (i.v. bolus by a push 
injection) in hospital, continues with the daily s.c. study drug administration in addition to the 
PE sessions (including PE as part of a tapering regimen) and continues for 30 days after the 
last PE procedure, both in hospital and ambulatory after hospital discharge. There is a 
maximum possible treatment duration of 90 days after first administration of the study drug.  
For details on adjunctive treatment with the study drug, please refer to Section 7.1. 
 
The following procedures must be recorded or performed: 
• 
Concomitant medication taken since the screening and baseline must be recorded on 
the Concomitant Medications page of the CRF. Concomitant medications initiated, 
stopped, up-titrated or down-titrated for an AE will also be recorded on a specific 
Concomitant Medications page of the CRF. This must be performed daily during daily 
PE period, on the first day after the daily PE period and then weekly for the 
subsequent time interval until the last day of study drug administration. 
• 
Transfusion of RBC units will be recorded according to Section 8.2.1.1. This will be 
done for each transfusion. Data will be recorded as concomitant medication. 
• 
PE information will be recorded according to Section 8.2.1.1. This will be done for 
each and all PE sessions. This includes concomitant medication specific to the PE 
session. 
• 
Peripheral and central blood line placement and replacement for PE will be recorded 
according to Section 8.2.1.1. This will be done for each blood line placement and 
replacement. 
• 
Clinical assessment will include physical examination and vital signs (blood pressure 
and heart rate at rest, body temperature). This must be performed daily during daily 
PE period, on the first day after the daily PE period and then weekly for the 
subsequent time interval until the last day of study drug administration. 
• 
AE recording will be performed daily during daily PE period, on the first day after the 
daily PE period and then weekly for the subsequent time interval until the last day of 
study drug administration. All AEs will be recorded. 
• 
The Glasgow Coma Score will be determined using the Glasgow Coma Scale 
(original scale). This score will be obtained weekly if the Glasgow coma score was 
abnormal at screening and as long as the subject is hospitalised in the investigative 
centre. 
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• 
The neurocognitive battery, if NOT performed at baseline, will be administered once 
as soon as possible, i.e., when level of consciousness and attentiveness of the 
subject permits and environmental factors are appropriate to support neurocognitive 
testing (e.g., subject is able to sit upright and interact with computer touch screen; 
subjects have eyeglasses used for reading and hearing devices, if applicable; testing 
area is quiet and relatively free of distracting stimuli).  
• 
The bleeding score according to the modified ITP bleeding score will be performed 
daily during daily PE period, on the first day after the daily PE period and then weekly 
for the subsequent time interval until the last day of study drug administration. 
• 
Assessment of clinically relevant bleeding will be performed daily during daily PE 
period, on the first day after the daily PE period and then weekly for the subsequent 
time interval until the last day of study drug administration. 
• 
12-lead ECG daily during the hospitalisation if it was abnormal at baseline. In 
addition, an ECG will be taken on day 1 and day 4, 4-6 hours post-study drug even 
when ECG was normal at baseline. The ECG will also be performed at pre-discharge 
and weekly after discharge until the last day of study drug administration.  
 
Sampling for local laboratory: 
• 
Blood sampling for chemistry will include the following: glucose, AST, ALT, LDH, 
CRP, creatinine, urea (BUN), uric acid, protein, albumin, haptoglobin, Na, K, Ca, Mg 
and Cl (local laboratory). The blood sample will be drawn daily during daily PE period, 
on the first day after the daily PE period and then weekly until the last day of study 
drug administration. 
• 
Blood sampling for haematology will include the following: haemoglobin, haematocrit, 
MCV, MCH, MCHC, full blood count including RBC, WBC, differential, reticulocytes, 
optical platelet count and immature platelet fraction (local laboratory). In case optical 
platelet counts are not available, they can be replaced by measurements based upon 
impedance. If not available in the local laboratory, immature platelet fraction 
measurements can be omitted; The blood sample will be drawn daily during daily PE 
period, on the first day after the daily PE period and then weekly until the last day of 
study drug administration.  
• 
Blood sampling for coagulation variables will include: fibrinogen, aPTT, PT, INR, vWF 
Ag and FVIII chromogene (local laboratory). In case FVIII chromogene is not 
available in the local laboratory, it can be replaced by an alternative method (e.g. one 
stage clotting assay). The blood samples will be drawn on Mondays, Wednesdays, 
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and Fridays during daily PE period, on the first day after the daily PE period and then 
weekly until the last day of study drug administration. 
• 
Blood sampling for markers for cardiac cell death: Troponin T (local laboratory). Daily 
during daily PE period, on the first day after the daily PE period and then weekly until 
the last day of study drug administration. In case the two initial measurements 
indicate that values are < ULN, all subsequent tests can be omitted. In case Troponin 
T is not available in the local laboratory, it can be replaced by Troponin I. 
• 
Blood sampling for markers for heart failure: BNP or NT-proBNP (local laboratory). 
The blood samples will be drawn on Mondays, Wednesdays, and Fridays during daily 
PE period, on the first day after the daily PE period and then weekly until the last day 
of study drug administration. In case the two initial measurements indicate that values 
are <ULN, all subsequent tests can be omitted. 
 
Sampling for central laboratory: 
• 
Blood sampling for markers for brain damage: NSE, Sβ100 (central laboratory). The 
blood samples will be drawn Mondays, Wednesdays, and Fridays during daily PE 
period, on the first day after the daily PE period and then weekly until the last day of 
study drug administration.  
• 
Blood sampling for RICO (central laboratory). Daily during daily PE period (pre-PE), 
on the first day after the daily PE period and then weekly until the last day of study 
drug administration. 
• 
Blood sampling for PK, vWF and FVIII assessments (all central laboratory) need to be 
taken at the following time points or time intervals: 
o During daily PE period: 
 
3 samples on day 1: at 5-10 min, 3-6 h, and 8-24 h post- i.v. 
administration of study drug, but prior to the second PE  
 
4 samples on day 2: after PE, but prior to s.c. study drug, and at 1-6 h, 
6-12 h, and 18-24 h post-study drug, but prior to the next PE 
 
1 sample on last day of PE: after PE, but prior to s.c. study drug 
o On first day after the daily PE period: 
 
4 samples: prior to study drug and at 1-6 h, 6-12 h, 18-24 h post-study 
drug, but prior to next administration of study drug or before next PE 
(in case of tapering) 
o Subsequent time interval until the last day of study drug administration: 
 
2 samples once-weekly: prior to study drug administration (but after 
PE, in case of tapering) and 4-8 h post-study drug. Of note, for each 
day that a follow-up at the investigational site is planned, the 
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administration of 10 mg study drug will be performed during the follow-
up visit in the investigational site. 
• 
Blood samples for ADA (central lab) need to be taken on day 14, and then weekly 
until the last day of study drug administration. 
• 
Blood sampling for ADAMTS13 and anti-ADAMTS13 antibody titre (central 
laboratory). This blood sampling needs to be performed on the first day after the daily 
PE period and 1 week post last day of PE (including tapering) and at 3 weeks post 
last day of PE (including tapering); the 1 week and 3 weeks after the very last PE 
(including tapering) sampling may be done at the weekly visit, even if not exactly 1 or 
3 weeks. 
• 
Retrieval of 30 mL from the first bag of pathological spent plasma resulting from the 
first PE procedure on study. This will be divided in aliquots of 5 mL each for storage 
at -70°C. The retrieved spent plasma, obtained from the first plasma exchange on 
study, and the first spent bag will be used for following purposes.  
o As matrix for development and validation of ADA, biomarker assays that will 
be used in TITAN trial. 
o For further characterisation of possible immunogenicity findings. 
o For additional measurement of vWF and ALX-0081 concentrations under R&D 
conditions and subsequent PK/PD modelling to assess extent of removal of 
these components upon plasma exchange. 
 
• 
Recuperate nurse sheet and/or AE diary at each post discharge visit. 
 
An overview of assessments performed during the treatment phase of this trial is provided in 
Table 11. 
 
Assessments scheduled in case of TTP exacerbation 
In case of TTP exacerbation, defined as recurrent thrombocytopenia following a response 
and requiring a re-initiation of daily PE treatment after ≥ 1 day but ≤ 30 days after the last 
daily PE, the assessments scheduled for “Day 1 after last daily PE” are not performed after 
completion of the exacerbation treatment, instead, the “post-daily PE (including tapering)” 
assessments are continued. A dedicated schedule of assessments is provided in Table 12. 
 
Assessments scheduled in case of TTP relapse 
Assessments scheduled in case of TTP relapse are discussed in section 8.1.3 (Table 14). 
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Table 11: 
Schedule of assessments during treatment phase. 
Assessment/ 
Activity 
Daily PE treatment phase  
Day 1 after last daily PE 
Post daily PE  
(including PE tapering) 
Treatment with study 
drug 
Once daily or twice daily  
(only if twice daily PE)a 
once daily 
once daily ± 2 hours 
Concomitant 
medication recording 
other than PE-related 
treatment 
all 
all 
weekly ± 2 days 
PE detailsb 
all 
NA 
NA or all in case of tapering 
Patient review/clinical 
assessment, 
including vital signs 
daily 
yes 
weekly ± 2 days 
AE recording 
daily (all) 
yes 
weekly ± 2 days (all) 
Glasgow Coma 
Score 
weekly if abnormal at screening 
if abnormal at screening 
weekly if abnormal at screening and if 
subject hospitalised 
Neurocognitive 
batteryc 
once, ASAPc 
no 
no 
Modified ITP bleeding 
score 
daily 
yes 
weekly ± 2 days 
Clinically relevant 
bleeding 
daily 
yes 
weekly ± 2 days 
12-lead ECG 
daily if abnormal at baseline. 
on day 1 and day 4, 4-6 h post-study drug 
yes 
weekly ± 2 days  
Blood chemistry 
(local lab) 
daily pre-PE 
yes 
weekly ± 2 days 
Haematology 
(local lab) 
daily pre-PE 
yes 
weekly ± 2 days 
Coagulation variables 
(local lab) 
Mon, Wed, Fridays 
yes 
weekly ± 2 days 
Cardiac marker (TnT 
or TnI) (local lab) 
daily pre-PE  
if value > ULN in baseline or at day 1 
if value > ULN in baseline or at day 1 
weekly ± 2 days  
if value > ULN in baseline or at day 1 
BNP or NT proBNP 
(local lab) 
 Mon, Wed, Fridays pre-PE 
if value > ULN in baseline or at day 1 
if value > ULN in baseline or at day 1 
weekly ± 2 days 
if value > ULN in baseline or at day 1 
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Assessment/ 
Activity 
Daily PE treatment phase  
Day 1 after last daily PE 
Post daily PE  
(including PE tapering) 
Brain damage 
markers (NSE, 
Sβ100) (central lab) 
Mon, Wed, Fridays pre-PE 
yes 
weekly ± 2 days 
PK 
(central lab) 
• 3 samples on day 1: at 5-10 min, 3-6 h, 8-24 h 
post-i.v. administration, but prior to second PE;  
• 4 samples on day 2: after PE, but prior to study 
drug, and at 1-6 h, 6-12 h, 18-24 h post-study 
drug, but prior to next PE;  
• 1 sample on last day of PE: after PE, but prior 
to study drug 
4 samples:  
• prior to study drug 
• 1-6 h post study drug 
• 6-12 h post study drug 
• 18-24 h post-study drug, but prior to 
next administration of study drug, or 
before next PE (in case of tapering) 
2 samples weekly: 
• prior to study drug, but after PE (in 
case of tapering)  
• 4-8 h post-study drug 
RICO (central lab) 
daily pre-PE 
yes 
weekly ± 2 days  
(pre-PE in case of tapering) 
vWF (central lab) 
coupled to PK above 
coupled to PK above 
coupled to PK above 
FVIII chromogene 
(central lab) 
coupled to PK above 
coupled to PK above 
coupled to PK above 
ADA (central lab) 
only on day 14 (when at least 14 days of PE 
would be needed)  
only on Day 14 (if not performed 
previously). 
weekly until the last day of study drug 
administration 
ADAMTS13 and anti-
ADAMTS13 antibody 
titre (central lab) 
no 
yes 
1 week and 3 weeks after the very last 
PE, including taperinge 
Spent plasma 
retrieval 
once, first PE on study, first spent bag 
no 
no 
Recuperate nurse 
sheet and/or AE diary 
NA 
NA 
Post-hospital discharge:  
weekly ± 2 daysd 
First PE on study: see section 4.2 
a Once or twice daily as detailed in the Treatment and Dosing Regimen for study drug Section 7.2 (Table 8). 
b Including concomitant medication related and simultaneous to PE procedure. 
c As soon as level of consciousness and attentiveness of the subject permits and environmental factors are appropriate to support neurocognitive testing 
d Post-discharge bleeding and any other AEs will be recorded daily by the medically trained person administering the study drug. The medically trained person will be instructed 
to contact the investigator in case of unexpected or clinically relevant findings 
e The 1-week and 3-weeks after the last day of PE (including tapering) sampling may be done at the weekly visit, even if not exactly 1 or 3 weeks 
Blood chemistry includes glucose, AST, ALT, LDH, CRP, creatinine, urea (BUN), uric acid, protein, albumin, haptoglobin, Na, K, Ca, Mg and Cl. 
Haematology includes haemoglobin, haematocrit, MCV, MCH, MCHC, full blood count including RBC, WBC, differential, reticulocytes, optical platelet count and immature 
platelet fraction. Coagulation variables include fibrinogen, aPTT, PT, INR, vWF:Ag and FVIII (chromogene or alternative method). 
 
 
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Table 12: 
Schedule of assessments during treatment phase in case of exacerbation. 
Assessment/ 
Activity 
Daily PE treatment phase  
Post daily PE  
(including PE tapering) 
Treatment with study drug 
Once daily or twice daily  
(only if twice daily PE)a 
once daily ± 2 hours 
Concomitant medication recording other than PE-
related treatment 
all 
weekly ± 2 days 
PE detailsb 
all 
NA or all in case of tapering 
Patient review/clinical assessment, including vital 
signs 
daily 
weekly ± 2 days 
AE recording 
daily (all) 
weekly ± 2 days (all) 
Glasgow Coma Score 
weekly if abnormal at screening 
weekly if abnormal at screening and if subject 
hospitalised 
Neurocognitive battery 
no 
no 
Modified ITP bleeding score 
daily 
weekly ± 2 days 
Clinically relevant bleeding 
daily 
weekly ± 2 days 
12-lead ECG 
daily if abnormal at baseline. 
on day 1 and day 4, 4-6 h post-study drug 
weekly ± 2 days  
Blood chemistry (local lab) 
daily pre-PE 
weekly ± 2 days 
Haematology (local lab) 
daily pre-PE 
weekly ± 2 days 
Coagulation variables (local lab) 
Mon, Wed, Fridays 
weekly ± 2 days 
Cardiac marker (TnT or TnI) (local lab) 
daily pre-PE  
if value > ULN in baseline or at day 1 
weekly ± 2 days  
if value > ULN in baseline or at day 1 
BNP or NT proBNP (local lab) 
 Mon, Wed, Fridays pre-PE 
if value > ULN in baseline or at day 1 
weekly ± 2 days 
if value > ULN in baseline or at day 1 
Brain damage markers (NSE, Sβ100) (central lab) 
Mon, Wed, Fridays pre-PE 
weekly ± 2 days 
PK 
(central lab) 
No 
2 samples weekly: 
• prior to study drug, but after PE (in case of 
tapering)  
• 4-8 h post-study drug 
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Assessment/ 
Activity 
Daily PE treatment phase  
Post daily PE  
(including PE tapering) 
RICO (central lab) 
daily pre-PE 
weekly ± 2 days  
(pre-PE in case of tapering) 
vWF (central lab) 
No 
coupled to PK above 
FVIII chromogene 
(central lab) 
No 
coupled to PK above 
ADA (central lab) 
No 
weekly until the last day of study drug 
administration 
ADAMTS13 and anti-ADAMTS13 antibody titre 
(central lab) 
No 
1 week and 3 weeks after the very last PE, 
including taperinge 
Spent plasma retrieval 
No 
no 
Recuperate nurse sheet and/or AE diary 
NA 
Post-hospital discharge:  
weekly ± 2 daysd 
a Once or twice daily as detailed in the Treatment and Dosing Regimen for study drug Section 7.2 (Table 8). 
b Including concomitant medication related and simultaneous to PE procedure. 
c As soon as level of consciousness and attentiveness of the subject permits and environmental factors are appropriate to support neurocognitive testing 
d Post-discharge bleeding and any other AEs will be recorded daily by the medically trained person administering the study drug. The medically trained person will be instructed 
to contact the investigator in case of unexpected or clinically relevant findings 
e The 1-week and 3-weeks after the last day of PE (including tapering) sampling may be done at the weekly visit, even if not exactly 1 or 3 weeks 
Blood chemistry includes glucose, AST, ALT, LDH, CRP, creatinine, urea (BUN), uric acid, protein, albumin, haptoglobin, Na, K, Ca, Mg and Cl. 
Haematology includes haemoglobin, haematocrit, MCV, MCH, MCHC, full blood count including RBC, WBC, differential, reticulocytes, optical platelet count and immature 
platelet fraction. Coagulation variables include fibrinogen, aPTT, PT, INR, vWF:Ag and FVIII (chromogene or alternative method). 
 
 
 
 
 
 
 
 
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8.1.3 
Follow-up 
 
The following procedures have to be performed at scheduled follow-up visits counted in days 
and months after last study drug administration (3 days ± 1 day, 7 days ± 1 day,1 month ± 3 
days, 2 months ± 7 days, 3 months ± 15 days, 6 months ± 15 days, and 12 months ± 15 
days). Unless stated otherwise, a given action is to be performed at all scheduled follow-up 
visits: 
• 
Concomitant medication taken since the previous visit must be recorded on the 
Concomitant Medications page of the CRF. Concomitant medications initiated, 
stopped, up-titrated or down-titrated for an AE will also be recorded on a specific 
Concomitant Medications page of the CRF. Transfusion of RBC units will be recorded 
according to Section 8.2.1.1. This will be done for each transfusion. Data will be 
recorded as concomitant medication 
• 
Clinical assessment will include physical examination and vital signs (blood pressure 
and heart rate at rest, body temperature) 
• 
AE recording 
• 
The neurocognitive battery will be administered at the day 3±1 and 1 year follow-up 
visits only 
• 
Bleeding score according to the modified ITP bleeding score will be performed at the 
1 month follow-up visit 
• 
Assessment of clinically relevant bleeding will be performed at the 1 month follow-up 
visit 
• 
12-lead ECG at 1 m follow-up (± 3 days), 2 m follow-up (± 7 days), 3 m follow-up( ± 
15 days), 6 m follow-up ( ± 15 days), and 12 m follow-up (± 15 days) 
• 
Urine pregnancy testing at 1 m follow-up (± 3 day) and 3 m follow-up (± 3 day) visits 
(local) 
• 
Blood sampling for chemistry will include the following: glucose, AST, ALT, LDH, 
CRP, creatinine, urea (BUN), uric acid, protein, albumin, haptoglobin, Na, K, Ca, Mg 
and Cl (local laboratory) 
 
• 
Blood sampling for haematology will include the following: haemoglobin, haematocrit, 
MCV, MCH, MCHC, full blood count including RBC, WBC, differential, reticulocytes, 
optical platelet count and immature platelet fraction (local laboratory). In case optical 
platelet counts are not available, they can be replaced by measurements based upon 
impedance. If not available in the local laboratory, immature platelet fraction 
measurements can be omitted.  
• 
Blood sampling for coagulation variables will include: fibrinogen, aPTT, PT, INR, 
vWF:Ag and FVIII chromogene (local laboratory) In case FVIII chromogene is not 
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available in the local laboratory, it can be replaced by an alternative method (e.g. one 
stage clotting assay) 
• 
Blood sampling for markers for cardiac cell death: Troponin T (local laboratory) will be 
taken at the 1 m follow-up (± 3 day) and 12 m follow-up (± 3 day) visits. In case the 
two initial measurements indicate that values are <ULN, all subsequent tests can be 
omitted. In case Troponin T is not available in the local laboratory, it can be replaced 
by Troponin I 
• 
Blood sampling for markers for heart failure: BNP or NT-proBNP (local laboratory). 
The blood samples will be drawn at the 1 m follow-up (± 3 day) and 12 m follow-up (± 
3 day) visits. In case the two initial measurements indicate that values are <ULN, all 
subsequent tests can be omitted 
• 
Blood sampling for markers for brain damage: NSE, Sβ100 (central laboratory). The 
blood samples will be drawn at the 1 m follow-up (± 3 day) and 12 m follow-up (± 3 
day) visits. 
• 
Blood sampling for PK and PD assessments (PD assessments include RICO, vWF, 
FVIII chromogene) (all central laboratory) need to be taken at the following time 
points or time intervals: 
o day 3 ± 1 day  
o day 7 ± 1 day  
o 1m follow-up ± 3 day  
In addition, blood samples for vWF (central lab) and for FVIII chromogene (central 
lab) need to be taken at 2m, 3m, 6m and 12m follow-up visits 
• 
Blood sampling for ADA needs to be taken at 1m, 2m, 3m, 6m and 12m follow-up 
visits (central lab). 
• 
Blood sampling for ADAMTS13 and anti-ADAMTS13 antibody titre (central laboratory) 
needs to be taken at 1m and 12m follow-up visits 
• 
Recuperate the nurse sheet and/or AE diary card 
 
An overview of assessments performed during the follow-up phase of this trial is provided in 
Table 13. 
During this follow-up phase, there will be no administration of study drug. 
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Table 13: 
Schedule of assessments during follow-up. 
Assessment/ 
Activity 
Day 3 
(± 1 d) 
Day 7 
(± 1 d) 
1m 
follow-
up 
(± 3 d) 
2m 
follow-
up 
(± 7 d) 
3m 
follow-
up 
(± 15 d) 
6m 
follow-
up 
(± 15 d) 
12m 
follow-
up 
(± 15 d) 
AE and 
unscheduled 
visit 
Concomitant 
medication recording 
other than PE related 
treatment 
X 
X 
X 
X 
X 
X 
X 
X 
Physical examination 
and vital signs 
X 
X 
X 
X 
X 
X 
X 
X 
AE recording 
X 
X 
X 
X 
X 
X 
X 
X 
Neurocognitive 
battery 
X 
 
 
 
 
 
X 
 
Modified ITP 
bleeding score 
 
 
X 
 
 
 
 
X 
Assessment for 
clinically relevant 
bleeding 
 
 
X 
 
 
 
 
X 
12-lead ECG 
 
 
X 
X 
X 
X 
X 
X 
Urine pregnancy test 
(local lab) 
 
 
X 
 
X 
 
 
 
Blood chemistry 
(local lab) 
X 
X 
X 
X 
X 
X 
X 
X 
Haematology (local 
lab) 
X 
X 
X 
X 
X 
X 
X 
X 
Coagulation variables 
(local lab) 
X 
X 
X 
X 
X 
X 
X 
X 
Cardiac marker (TnT 
or TnI) (local lab) 
 
 
X 
 
 
 
X 
X 
BNP or NT proBNP 
(local lab) 
 
 
X 
 
 
 
X 
X 
Brain damage 
markers (NSE, 
Sβ100) (central lab) 
 
 
X 
 
 
 
X 
X 
PK (central lab) 
X 
X 
X 
 
 
 
 
If applicablea 
RICO (central lab) 
X 
X 
X 
 
 
 
 
If applicablea 
vWF (central lab) 
X 
X 
X 
X 
X 
X 
X 
X 
FVIII chromogene 
(central lab) 
X 
X 
X 
X 
X 
X 
X 
X 
ADA (central lab) 
 
 
X 
X 
X 
X 
X 
X 
ADAMTS13 and anti-
ADAMTS13 antibody 
titre (central lab) 
 
 
X 
 
 
 
X 
X 
Recuperate AE diary 
X 
X 
X 
X 
X 
X 
X 
If applicableb 
a i.e. during treatment phase with study drug. 
b i.e. post-hospital discharge 
Blood chemistry includes glucose, AST, ALT, LDH, CRP, creatinine, urea (BUN), uric acid, protein, albumin, 
haptoglobin, Na, K, Ca, Mg and Cl. Haematology includes haemoglobin, haematocrit, MCV, MCH, MCHC, full 
blood count including RBC, WBC, differential, reticulocytes, platelet count and, if available, immature platelet 
fraction. Coagulation variables include fibrinogen, aPTT, PT, INR, vWF:Ag and FVIII (chromogene or alternative 
method) 
 
 
 
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Precaution to be taken for cessation of study drug administration: 
As described in section 8.1.2, ADAMTS13 and anti-ADAMTS13 antibody titre will be 
measured from blood sampling at 1-week and 3-weeks after the last day of PE (including 
tapering). Note that the 1-week and 3-weeks after the last day of PE (including tapering) 
sampling may be done at the weekly visit, even if not exactly 1 or 3 weeks. 
The resulting data will be provided to the Investigator for information at the end of the study. 
In case an investigator has no access to similar assays and availability of ADAMTS13 and 
anti-ADAMTS13 antibody titre are considered essential for clinical decision making, an ad 
hoc determination of the results can be organised (under supervision of the country 
coordinator). 
Platelets and LDH will be measured from blood sampling on days 3 and 7 following the 
conclusion of study drug administration. If at any time the platelet count falls below 70% of 
the last platelet count prior to cessation of study drug administration, with concomitant LDH > 
1.5 X ULN: the subject will be considered at risk of a relapse and she/he will need to be 
closely monitored by the site staff. 
When practical and logistical circumstances prevail, the Investigator can decide to hospitalise 
a subject for observation in order to facilitate the follow up during these 7 days post-study 
drug treatment period. Such a hospitalisation, organised only for practical and logistic 
reasons and not triggered by clinical significant altered laboratory values nor by clinical signs 
or symptoms, should be considered as an elective hospitalisation to be captured as an 
additional visit, and not as an AE or SAE (please refer to section 9.1.1).  
 
Assessments scheduled in case of TTP relapse 
In case of TTP relapse, defined as de novo event of TTP that occurs later than 30 days after 
the last daily PE, the assessments described under “daily PE for the treatment of relapse” 
are scheduled (see Table 14). Note that there are no “post-daily PE (including tapering)” 
assessments, instead, follow-up should continue per protocol. In case a follow-up visit was 
scheduled during the daily PE period, this visit is omitted. 
 
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Table 14: 
Schedule of assessments during daily PE for the treatment of a relapse. 
Assessment/Activity 
Daily PE for the treatment of a relapse 
Treatment with study drug 
No 
Concomitant medication recording other than PE-related treatment 
all 
PE detailsa 
all 
Patient review/clinical assessment, including vital signs 
daily 
AE recording 
daily (all) 
Glasgow Coma Score 
No 
Neurocognitive battery 
no 
Modified ITP bleeding score 
daily 
Clinically relevant bleeding 
No  
12-lead ECG 
daily if abnormal at baseline. 
on day 1 and day 4 
Blood chemistry (local lab) 
daily pre-PE 
Haematology (local lab) 
daily pre-PE 
Coagulation variables (local lab) 
Mon, Wed, Fridays 
Cardiac marker (TnT or TnI) (local lab) 
daily pre-PE  
if value > ULN in baseline or at day 1 
BNP or NT proBNP (local lab) 
 Mon, Wed, Fridays pre-PE 
if value > ULN in baseline or at day 1 
Brain damage markers (NSE, Sβ100) (central lab) 
No 
PK (central lab) 
No 
RICO (central lab) 
No 
vWF (central lab) 
No 
FVIII chromogene (central lab) 
No 
ADA (central lab) 
No 
ADAMTS13 and anti-ADAMTS13 antibody titre (central lab) 
No 
Spent plasma retrieval 
No 
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Assessment/Activity 
Daily PE for the treatment of a relapse 
Recuperate nurse sheet and/or AE diary 
NA 
a Including concomitant medication related and simultaneous to PE procedure. 
Blood chemistry includes glucose, AST, ALT, LDH, CRP, creatinine, urea (BUN), uric acid, protein, albumin, haptoglobin, Na, K, Ca, Mg and Cl. 
Haematology includes haemoglobin, haematocrit, MCV, MCH, MCHC, full blood count including RBC, WBC, differential, reticulocytes, optical platelet count and immature 
platelet fraction. Coagulation variables include fibrinogen, aPTT, PT, INR, vWF:Ag and FVIII (chromogene or alternative method). 
 
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8.1.4 
Unscheduled Additional Visit 
 
In case of unscheduled additional visits, the following assessments will be performed at a 
minimum (Table 13): 
• 
Concomitant medication taken since the previous visit must be recorded on the 
Concomitant Medications page of the CRF. Concomitant medications initiated, 
stopped, up-titrated or down-titrated for an AE will also be recorded on a specific 
Concomitant Medications page of the CRF. Transfusion of RBC units will be recorded 
as concomitant medication 
• 
Clinical assessment will include physical examination and vital signs (blood pressure 
and heart rate at rest, body temperature) 
• 
Bleeding score according to the modified ITP bleeding score 
• 
Assessment of clinically relevant bleeding 
• 
AE recording 
• 
12-lead ECG 
• 
Blood sampling for chemistry will include the following: glucose, AST, ALT, LDH, 
CRP, creatinine, urea (BUN), uric acid, protein, albumin, Na, K, Ca, Mg and Cl (local 
laboratory) 
• 
Blood sampling for haematology will include the following: haemoglobin, haematocrit, 
MCV, MCH, MCHC, full blood count including RBC, WBC, differential, reticulocytes, 
optical platelet count and immature platelet fraction (local laboratory). In case optical 
platelet counts are not available, they can be replaced by measurements based upon 
impedance. If not available in the local laboratory, immature platelet fraction 
measurements can be omitted 
• 
Blood sampling for coagulation variables will include: fibrinogen, aPTT, PT, INR, 
vWF:Ag and FVIII chromogene (local laboratory). In case FVIII chromogene is not 
available in the local laboratory, it can be replaced by an alternative method (e.g. one 
stage clotting assay) 
• 
Blood sampling for markers for cardiac cell death: Troponin T (local laboratory). In 
case Troponin T is not available in the local laboratory, it can be replaced by 
Troponin I 
• 
Blood sampling for markers for heart failure: BNP or NT-proBNP (local laboratory) 
• 
Blood sampling for markers for brain damage: NSE, Sβ100 (central laboratory) 
• 
Blood sampling for PK and RICO, if applicable (additional visit during period of 
administration of study drug (central laboratory) 
• 
Blood sampling for vWF, FVIII chromogene, and for ADA (central laboratory) 
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• 
Blood sampling for ADAMTS13 and anti-ADAMTS13 antibody titre (central laboratory) 
• 
Recuperate the nurse sheet and/or AE diary, if applicable (additional visit post-
hospital discharge) 
 
8.1.5 
Exacerbation and relapse visits 
 
Additional information on the assessments performed during TTP exacerbation and relapse 
is included in sections 8.1.2 and 8.1.3 respectively. 
 
8.2 
Assessment of Efficacy 
 
8.2.1 
Clinical Outcome 
 
• 
Time-to-response of treatment, defined by a recovery of platelets ≥ 150,000/µL. This 
response must be confirmed at 48 hours after the initial reporting of platelet recovery 
above 150,000/µL by a de novo measure of platelets ≥ 150,000/µL and LDH ≤ 2 X 
ULN  
• 
Number of subjects with complete remission 
• 
Number of (subjects with) exacerbations of TTP and time to first exacerbation of TTP. 
Exacerbation is defined as recurrent thrombocytopenia following a response and 
requiring a re-initiation of daily PE treatment after ≥ 1 day but ≤ 30 days after the last 
daily PE.1 
• 
Number of subjects relapsing of TTP (defined as de novo event of TTP that occurs 
later than 30 days after the last daily PE) for a maximum of 1 year, and time to first 
relapse of TTP 
• 
Daily PE data, including serious adverse events (SAEs) related to daily PE treatment 
• 
Neurocognitive function, as measured by a neurocognitive test battery, at complete 
remission and at 1 year follow up. This test will be preceded by the Glasgow Coma 
Score to measure the state of consciousness of the subject 
• 
Improvement of organ dysfunction and improvement of TTP related signs and 
symptoms 
• 
Total mortality within the daily PE treatment period and within the subsequent study 
drug treatment period (including tapering) 
• 
Determination of biomarkers of TTP including but not limited to disintegrin-like and 
metalloprotease with thrombospondin repeats 13 (ADAMTS13) levels and anti-
ADAMTS13 antibody titres (see also PD assessments) 
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8.2.1.1 
Outcomes of Special Interest 
 
8.2.1.1.1 Plasma exchange 
 
PE is the principal therapy of this pathology. PE will be described and recorded in detail 
throughout the study. This includes the initial series of PE sessions, as well as any further PE 
sessions that may be administered after interruption of the previous session. All PE sessions 
arising prior to remission and ultimately within 1 year after inclusion into the study will be 
recorded. 
 
The following minimum details will be required, for each PE session: 
1. Start date/time and end date/time of each procedure 
2. Completion as planned or interruption needed and reason thereof 
3. Plasma replacement 
a. Type of plasma product used 
b. ABO group used 
c. Total number of units used during the PE session 
d. Total volume used for plasma replacement during the PE session 
4. Anticoagulant administered, if any, for the PE session 
5. Concomitant medication administered specifically as part of the PE procedure and 
during the course of the PE session will be recorded separately. Other concomitant 
medication, such as methylprednisone will be reported in the concomitant medication 
other than PE-related medication. 
Medication given in response to a PE-related AE (i.e. antibiotic administration due to 
a central line infection) will be reported in the concomitant medication other than PE-
related medication. This also includes immunosuppressive and other treatments 
adjunctive to PE (i.e. methylprednisone, rituximab). 
 
8.2.1.1.2 Transfusion of RBC 
 
Transfusion of RBC will be described by: 
• 
Number of RBC units 
• 
Date/time of administration 
• 
This data is entered in the concomitant medication other than PE. 
 
 
 
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8.2.1.1.3 Peripheral and/or central blood line placement and replacement for daily PE 
 
Each placement and replacement will be described for: 
• 
Central or peripheral access 
• 
Implant date/time and removal date/time of each central access 
• 
Material used and anatomical point of entry 
• 
Results of culture after removal 
 
8.2.1.1.4 Supportive measures 
 
Supportive measures will be described in concomitant medication other than PE. 
 
8.2.1.1.5 Modified ITP bleeding score 
 
This bleeding score is described in Section 8.3.3. 
 
8.2.1.1.6 Neurocognitive battery 
 
This test battery is described in the Section 8.3.6. 
 
8.2.2 
Pharmacodynamics 
 
Sampling 
Pharmacodynamic parameters listed below will be assessed by a central laboratory. Blood 
samples for laboratory parameters will be collected as scheduled in Table 10 (screening and 
baseline), Table 11 (treatment phase) and Table 13 (follow-up).  
• 
RICO (conducted at central lab) 
• 
vWF, including vWF:Ag and vWF propeptide (conducted at central lab) 
• 
FVIII chromogene (conducted at central lab) 
 
Instructions for the handling of laboratory samples are in a separate Laboratory Manual. 
 
Labelling and shipping procedures for PD samples 
Sites will receive required material for sampling before the start of the study. The tubes will 
be labelled and will carry the following information: 
• 
Type of sample, e.g., blood, urine, etc. 
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• 
Study number 
• 
Subject number 
• 
Sample number  
• 
Scheduled time of sampling 
 Instructions for the handling of laboratory samples are in a separate Laboratory Manual. 
 
8.2.3 
Laboratory Markers of Disease 
 
Disease markers listed below will be assessed by a central or local laboratory. Blood 
samples will be collected as scheduled in Table 10 (screening and baseline), Table 11 
(treatment phase) and Table 13 (follow-up).  
• 
ADAMTS13 and anti-ADAMTS13 antibody titre (central laboratory) 
• 
Cardiac marker (TnT or TnI) 
• 
BNP or NT proBNP 
• 
Brain damage markers (NSE, Sβ100) (central laboratory) 
• 
PD (see Section 8.2.2 above) 
 
8.3 
Assessment of Safety 
 
8.3.1 
Safety Laboratory Monitoring 
 
Blood samples for laboratory parameters will be collected as scheduled in Table 10 
(screening and baseline), Table 11 (treatment phase) and Table 13 (follow-up).  
All safety laboratory parameters will be performed at each local site laboratory. For each 
local laboratory, the Investigator will provide Ablynx with the name, professional degree and 
curriculum vitae of the laboratory director, a copy of the laboratory's certification- and the 
normal ranges for each parameter being evaluated in the study. These laboratory references 
must be forwarded to Ablynx before study start and updated whenever necessary. However, 
the Investigator will request that the clinical laboratory does not change any normal range 
during the course of the study. 
Instructions for the handling of laboratory samples are in a separate Laboratory Manual. 
Virus serology will be measured at screening only. The samples will be sent to the local 
laboratory as soon as possible after blood sampling. 
Laboratory data will be transmitted electronically from the laboratory, to the study site. A 
print-out of the laboratory results will be added to the source documents. Each parameter 
outside the normal range will be assigned as H (high) or L (low) on the laboratory sheet. The 
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Investigator has to interpret each “outside the normal range” value as n.c.s. (not clinically 
significant) or c.s. (clinically significant). In the latter case the Investigator has to give a 
comment and the deviation is judged as an AE or SAE as appropriate. 
 
Laboratory parameters  
For all the items below the name of the laboratory, units of each parameter and normal range 
(lower limit of normal (LLN) and ULN) must be specified. 
• 
Haematology 
o Full blood count, including haemoglobin, haematocrit, MCV, MCH, MCHC, full 
blood count including: RBC, WBC and differential blood count 
o Reticulocytes 
o Optical platelet count (if not available, can be replaced by measurement 
based upon impedance) 
o Immature platelet fraction (can be omitted) 
• 
Blood chemistry 
o Glucose 
o Bilirubin (total) 
o AP 
o AST 
o ALT 
o LDH 
o CRP 
o hCG (for women, only if urine pregnancy test is not feasible or inconclusive) 
o Rheumatoid factor 
o Antinucleic acid 
o Iron, ferritin, transferrin 
o Creatinine, urea (BUN), uric acid 
o Protein, albumin 
o Na, K, Ca, Mg, Cl 
• 
Urinanalysis 
o pH  
o Specific gravity  
o Protein  
o Glucose  
o Ketones  
o Bilirubin  
o Blood  
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o Nitrite  
o Urobilinogen  
o Leukocytes  
• 
Urine pregnancy test for female subjects (hCG only) 
• 
Virus serology 
o HIV1 and HIV2 antibodies at screening 
o Surface antigen of HBV (HbsAg) and HCV antibodies at screening 
• 
Coagulation variables 
o aPTT 
o PT 
o INR 
o Fibrinogen 
o vWF:Ag 
o FVIII chromogenic or alternative method (e.g. one stage clot test) 
o Lupus anticoagulant 
o Anticardiolipin antibodies (antiphospholipid) 
• 
Blood typing (ABO and Rh) and DAT  
 
8.3.2 
Physical Examination and Vital Signs 
 
A complete patient review and clinical assessment including vital signs will be performed at 
screening, during treatment phase and during follow-up, as indicated in Table 10, Table 11 
and Table 13, respectively. 
 
Blood pressure (systolic and diastolic) shall always be measured on the same arm 
(preferentially on the left arm). Heart rate measurements will be performed manually. Body 
temperature will be measured by the standard means of the investigational site. 
Measurements shall be recorded from the subject in the lying position after having rested for 
a 5-minute period.  
 
After drug administration, inspections for vascular effects will focus on checks for bruising, 
haematomas, bleeding at injection and puncture sites and shaving nicks, gingival 
haemorrhage after brushing teeth, epistaxis and urinary blood loss or any other unusual 
bleeding. Specific questioning will be performed on whether subjects have experienced 
bleeding or bruises since the last examination. 
 
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8.3.3 
Bleeding Events 
 
Clinically relevant bleeding 
Incidence of clinically relevant bleeding will be reported. Clinically relevant bleeding is 
defined as moderate to severe (including life-threatening) bleeding requiring urgent medical 
and/or surgical intervention. 
 
Modified ITP bleeding score 
Bleeding will also be measured using a modified version of the immune thrombocytopenic 
purpura (ITP) bleeding score. The rationale for using a modified version of the ITP bleeding 
score is the following. Both the WHO bleeding scale and other bleeding scales used in the 
frame of cardiac intervention or treatment of venous thromboembolism include bleeding or 
blood loss requiring transfusion of packed RBC or whole blood as a severity factor. It is 
common for subjects undergoing PE to need transfusions, even without apparent bleeding. 
The ITP bleeding score27 does not include transfusion data. It is expected to be more 
sensitive than the other bleeding scales mentioned above. The modified ITP bleeding score 
is the sum of the scores for each line (Table 15). 
 
Table 15: 
Modified ITP bleeding score. 
Grade 
0 
1 
2 
Skin: petechiae 
None 
Scattered petechiae 
Diffuse petechiae 
Skin: ecchymosis 
None 
1-5 bruises 
>5 bruises with size > 2cm 
Oral 
None 
1 blood blister or >5 
petechiae or gum bleeding 
<5 min 
Multiple blood blisters or gum 
bleeding >5 min 
Epistaxis 
None 
Blood when blowing nose or 
epistaxis <5 min (per 
episode) 
Epistaxis >5 min (per episode) 
Ocular 
None 
Subconjunctival 
haemorrhage 
 
Intracranial 
None 
 
Haemorrhage 
Gastrointestinal 
None 
Blood when wiping 
Blood present on stool 
Urinary 
None 
Dipstick greater than trace 
Macroscopic  
Gynaecological 
Normal 
period 
Spotting outside of normal 
period 
Bleeding greater than spotting 
outside of normal period, or 
very heavy period 
Pulmonary 
None 
Haemoptysis 
Haemorrhage 
 
Clinically relevant findings that are observed prior to study drug initiation must be recorded 
on the relevant Medical History source documents page. Abnormalities in local tolerability will 
be reported via AE reporting throughout the trial. Clinically relevant findings found after study 
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drug initiation and meeting the definition of an AE (new AE or worsening of previously 
existing condition) must be recorded on an AE page of the source documents. 
 
8.3.4 
Cardiovascular Monitoring 
 
12-lead ECGs will be performed at the time points specified in Table 10 (baseline), Table 11 
(treatment phase) and Table 13 (follow-up). ECGs will be conducted with respect to the 
following procedure. Subjects will be in horizontal position during the measurements. ECGs 
will be evaluated and classified as normal/abnormal. In case of “abnormal”, the abnormality 
has to be described. Heart rate, PR, QRS, QT and QTc (Bazett) will be entered into the 
database. Bazett is automatically calculated by the ECG apparatus and provided on the 
print-out. Fridericia and RR will be calculated from the available data. For the baseline ECG, 
one recording will be made. The 12-lead ECGs will be recorded after the subjects have 
rested for at least five minutes in supine position. Six limb leads, as specified by Einthoven (I, 
II and III) and Goldberger (aVR, aVL, aVF), and six precordial leads (V1–V6), according to 
Wilson, will be used. The ECG will be recorded at a paper speed of 25 mm/s and a standard 
calibration of 1 mV (= 10 mm). Each ECG will include the following information: identification 
of each lead, study number, subject number, paper speed, voltage calibration as well as date 
and time of the recording. This procedure will also be followed for unscheduled visits. 
 
8.3.5 
Glasgow Coma Score 
 
The Glasgow Coma Score will be determined using the Glasgow Coma Scale (original 
scale), which is a neurological scale that measures the conscious state of the subject. The 
best eye, verbal and motor responses will be scored according to the scale, and the separate 
scores added up to obtain the final score, ranging from 3 to 15. 
 
8.3.6 
Neurocognitive Battery 
 
The neurocognitive battery, consisting of the CNTB and two manually-administered, pencil-
and-paper tests (Category Fluency and Letter Fluency), will be administered at the following 
time points:  
• 
Baseline (only if the level of consciousness and attentiveness of the subject permits 
and environmental factors are appropriate to support neurocognitive testing) 
• 
Treatment phase 
o Once as soon as possible during the PE treatment phase (i.e., as soon as the 
level of consciousness and attentiveness of the subject permits and 
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environmental factors are appropriate to support neurocognitive testing) and 
only if the subject’s condition did not allow to perform the CNTB at baseline 
• 
Follow-up 
o At 3 days ± 1 days 
o At 12 months ± 15 days 
 
Only appropriately trained and Sponsor-approved testers may administer the neurocognitive 
battery to study subjects. The Principal Investigator will be responsible for ensuring that 
his/her staff conduct the testing according to the protocol and any training guidelines 
provided for the battery. When testing occurs in the clinic setting, subjects should be tested 
in the same room under constant environmental conditions such as lighting, heating and 
noise. When testing occurs outside of the clinic setting, e.g., at bedside, the tester should 
ensure that the subject is able to sit upright and interact with computer touch screen and the 
testing area is quiet and relatively free of extraneous, distracting stimuli. Subjects who wear 
hearing devices or eyeglasses for reading will wear them when completing the 
neurocognitive assessments. 
  
8.3.6.1 
CNTB 
 
The CNTB is an assessment tool for the computerised testing of neuropsychological 
function. The standard CNTB has 15 modules that can be combined in a customised manner 
to measure specific cognitive domains of interest. The customised set of modules is 
administered in a standardised order and with standardised stimulus durations. In this study, 
6 CNTB modules will be administered (with approximate time to administer) in the sequence 
that follows: 
 
Word List Learning and Selective Reminding (WLL/SR)  
approx. 7 minutes 
Choice Reaction Time (CRT) 
 
 
 
 
approx. 2.5 minutes 
Visual Memory (VMEM)  
 
 
 
 
approx. 5 minutes 
Simple Reaction Time (SRT) 
 
 
 
 
approx. 2 minutes 
Working Memory (WMEM) 
 
 
 
 
approx. 2.5 minutes 
Word List Learning and Delayed Recall (WLL/DR) 
 
approx. 2 minutes 
 
A word list learning test will be administered to evaluate verbal learning and memory (verbal 
rote memorisation). It has 2 components: an initial learning component utilising selective 
reminding (WLL/SR) and a delayed recall component (WLL/DR). A test requiring memory of 
novel shapes (VMEM) will be given to evaluate visual learning and memory (visual rote 
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memorisation). Information processing speed will be measured by tests of SRT and CRT. 
The CRT, together with a WMEM test, will be used to measure complex attention and 
concentration. This customised CNTB battery will take approximately 21 minutes to 
complete. 
 
8.3.6.2 
Category Fluency Test 
 
In this test, subjects are required to produce as many examples of a given category (e.g., 
animals, vegetables) as quickly as possible within a specified time period. A higher number 
indicates better performance. The category fluency test assesses rapid language generation 
and depends on sustained attention, verbal intelligence, cognitive flexibility and efficiency of 
semantic processing. The category fluency test takes approximately 2-3 minutes to 
administer. 
 
8.3.6.3 
Letter Fluency Test 
 
This test measures the number of correct words generated by the subject within one minute, 
where the generated words are required to begin with three predefined letters (which differ, 
depending on the language in which the scale is being used). A higher number indicates a 
better performance. The letter fluency test assesses rapid language generation and depends 
on sustained attention, verbal intelligence, cognitive flexibility and efficiency of semantic 
processing. The letter fluency test takes approximately 5-6 minutes to administer. 
 
8.3.7 
Adverse Events 
 
It is the responsibility of the Investigator to document all AEs which occur during the entire 
study period, up to the last follow-up visit.  
All AEs occurring after the start of the study must be reported. Subjects entry into the study is 
defined as the time at which informed consent is obtained. All subsequent AEs, irrespective 
of whether no drug, active drug or placebo has been administered, must be recorded 
regardless of whether or not they are considered to be drug related. 
At each assessment, all AEs either observed by the Investigator or one of his clinical 
collaborators, or reported by the subject spontaneously or in a response to a direct question 
must be evaluated by the Investigator and noted in the AE sections of the subject’s CRF.  
Any clinically significant changes in laboratory parameters and all deviations of coagulation 
parameters outside normal range will be recorded as (an) AE(s) in the relevant section of the 
CRF.  
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The non-leading question "Have you felt different in any way over the last few days?" will be 
asked at baseline and the question "Do you feel different in any way since starting the new 
treatment/the last assessment?" will be asked at regular intervals throughout the study. The 
responses will be recorded in the subject’s CRF. 
The nature of each event, date and time of onset, duration, severity and relationship to 
treatment should be established. Details of changes to the dosage schedule or any 
corrective treatment should be recorded on the appropriate pages of the CRF. 
The Investigator should follow-up subjects with AEs until the event has subsided 
(disappeared) or until the condition has stabilised. Reports relative to the subject’s 
subsequent course must be submitted to the clinical study monitor. 
For more details, refer to section 9. 
 
8.3.8 
Immunogenicity 
 
ADA in serum will be determined by an appropriate assay technique. Immunogenicity testing 
will be performed on the timepoints indicated in Table 10 (screening and baseline), Table 11 
(treatment phase) and Table 13 (follow-up). The sample analysis will be done by Ablynx NV. 
A full description of the ADA assay is provided in the separate Laboratory Manual. 
A separate immunogenicity report will be prepared and presented as an Appendix to the 
Final Clinical Study Report. 
 
 
8.4 
Pharmacokinetic Assessment 
 
8.4.1 
Sampling 
 
Blood sampling for PK assessment will take approximately 1 minute. A detailed overview for 
the sampling times is presented in Table 10 (screening and baseline), Table 11 (treatment 
phase) and Table 13 (follow-up). 
In case several study procedures are scheduled at the same time point, the following 
sequence should be followed: asking for AEs, ECG, vital signs, PK blood sampling and blood 
sampling for clinical laboratory tests. Enough time should be reserved for all assessments to 
be performed so that the administration of study drug and the PK blood sampling is done at 
the scheduled time point. 
All assessments have to be scheduled in a way that the time point of PK sampling is strictly 
kept as displayed in Table 10, Table 11 and Table 13. 
Instructions for the handling of laboratory samples are in a separate Laboratory Manual. 
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8.4.2 
Labelling and Shipping Procedures for PK Samples 
 
Sites will receive required material for sampling before the start of the study. The tubes will 
be labelled and will carry the following information: 
• 
Type of sample, e.g., blood, urine, etc. 
• 
Study number 
• 
Subject number 
• 
Sample number  
• 
Scheduled time of sampling 
 Instructions for the handling of laboratory samples are in a separate Laboratory Manual. 
 
8.4.3 
Analytical Assays 
 
The concentrations of ALX-0081 in plasma will be determined using a validated assay. 
Concentrations will be calculated by interpolation from a calibration curve. Quality control 
samples will be analysed throughout the study. Their measured concentrations will be used 
to determine between-run, overall precision and accuracy of the analyses. 
 
8.4.4 
Pharmacokinetics 
 
Predose plasma concentrations against time will be plotted to demonstrate attainment of 
steady state. 
A separate PK-report will be written and presented as an Appendix to the final Clinical Study 
Report. 
The plasma concentration-time data of ALX-0081 will be analysed using population PK 
modeling. Typical population values of basic PK parameters will be estimated together with 
the inter-individual variability. Effects of subject demographics, laboratory parameter values, 
and other covariates on the pharmacokinetics of ALX-0081 will be explored. The results of 
the population PK analysis will be reported in an independent Modeling and Simulation 
report. 
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9. 
SAFETY DEFINITIONS AND REPORTING REQUIREMENTS 
 
9.1 
Adverse Events 
 
9.1.1 
Definitions of Adverse Events 
 
An AE is “any untoward medical occurrence in a patient or clinical investigation subject 
administered a study drug and which does not necessarily have a causal relationship with 
this treatment”. An AE can therefore be any unfavourable and unintended sign (including an 
abnormal laboratory finding), symptom, or disease temporally associated with the use of a 
study drug, whether or not related to the study drug.  
A treatment-emergent AE is any AE temporarily associated with the use of a study drug, 
whether or not considered related to the study drug. 
AEs include: 
• 
Exacerbation of a pre-existing disease 
• 
Increase in frequency or intensity of a pre-existing episodic disease or medical 
condition 
• 
Disease or medical condition detected or diagnosed after study drug administration 
even though it may have been present prior to the start of the study 
• 
Continuous persistent disease or symptoms present at baseline that worsen following 
the start of the study 
• 
Lack of efficacy in the acute treatment of a life-threatening disease 
• 
Events considered by the Investigator to be related to study-mandated procedures 
• 
Abnormal assessments, e.g., ECG, vital signs or physical examination findings, must 
be reported as AEs if they represent a clinically significant finding that was not 
present at baseline or worsened during the course of the study 
• 
Laboratory test abnormalities must be reported as AEs if they represent a clinically 
significant finding, symptomatic or not, which was not present at baseline or 
worsened during the course of the study  
AEs do not include: 
• 
Medical or surgical procedure, e.g., surgery, endoscopy, tooth extraction, transfusion. 
However, the event leading to the procedure is an AE. If this event is serious, the 
procedure must be described in the SAE narrative 
• 
Pre-existing disease or medical condition that does not worsen 
• 
Situations in which an adverse change did not occur, e.g., hospitalisations for 
cosmetic elective surgery or for social and/or convenience reasons, or elective 
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hospitalisation for observation in order to facilitate the follow-up when practical and 
logistical circumstances exist.  
• 
Overdose of either study drug or concomitant medication without any signs or 
symptoms. However, overdose must be mentioned in the Study Drug Log 
 
9.1.2 
Definition of Adverse Reaction (AR) 
 
An AR is a noxious and unintended response to a study drug irrespective of the dose 
administered. 
All ARs are judged by either the reporting Investigator or the Sponsor as having a reasonable 
causal relationship to the study drug. The expression reasonable causal relationship means 
to convey in general that there is evidence or argument to suggest a causal relationship. 
An unexpected adverse reaction is an AR, the nature or severity of which is not consistent 
with the information available on the study drug (i.e. the current Investigator's Brochure). 
 
9.1.3 
Intensity of Adverse Events 
 
The intensity of clinical AEs is graded on a three-point scale: mild, moderate, severe and 
reported on specific AE pages of the source documents. 
If the intensity of an AE worsens during study drug administration, the AE will be closed and 
a new AE with enhanced severity will be generated in the source documents. If the AE 
lessens in intensity, no change in the severity is required. 
If an AE occurs during a washout or placebo run-in phase and afterwards worsens during the 
treatment phase, a new AE page must be filled in with the intensity observed during study 
drug administration. 
• 
Mild 
Event may be noticeable to subject; does not influence daily activities; usually does 
not require intervention 
• 
Moderate 
Event may make subject uncomfortable; performance of daily activities may be 
influenced; intervention may be needed 
• 
Severe 
Event may cause noticeable discomfort; usually interferes with daily activities; subject 
may not be able to continue in the study; treatment or intervention is usually needed 
A mild, moderate or severe AE may or may not be serious. These terms are used to describe 
the intensity of a specific event (as in mild, moderate or severe myocardial infarction). 
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However, a severe event may be of relatively minor medical significance (such as severe 
headache) and is not necessarily serious. For example, nausea lasting several hours may be 
rated as severe, but may not be clinically serious. Fever of 39°C that is not considered 
severe may become serious if it prolongs hospital discharge by a day (see Section 9.2.1.1). 
Seriousness rather than severity serves as a guide for defining regulatory reporting 
obligations. 
 
9.1.4 
Classification according to CTCAE 
 
AEs will be classified by the Investigator according to CTCAE v4.0 in addition to severity. 
 
9.1.5 
Relationship to Study Drug  
 
AEs should be assessed by the Investigators as to whether or not there is a reasonable 
possibility of causal relationship to the study drug and reported as either related or unrelated. 
• 
Related to study drug 
This category applies to any AE (serious or not) with a causal relationship to the use 
of the study drug such as: 
− 
The event occurred in close temporal relationship to study drug administration 
− 
The event abated (diminished) or disappeared when treatment with the study 
drug was down-titrated, interrupted or discontinued 
− 
The event re-occurred when treatment was re-introduced 
− 
Cannot be explained by known features of the subject’s clinical condition 
 
• 
Possibly related to study drug 
This category applies to any AE (serious or not) that appears to have a reasonable 
possibility of causal relationship to the use of the study drug (i.e., a relationship 
cannot be ruled out). Guidelines to determine whether an event might be considered 
possibly related include (but are not limited to) the following: 
− 
Is a clinical event, including laboratory test with clinically significant 
abnormalities, within a reasonable time sequence to administration of the 
study drug 
− 
Environmental factors such as clinical state and other treatments could 
equally have caused the event 
− 
Information on study drug withdrawal may be lacking or unclear 
 
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• 
Unlikely/Not related to study drug 
This category applies to any AE (serious or not) that does not appear to have a 
reasonable relationship to the use of study drug (see above guidelines). 
According to current knowledge, the likelihood of a causal connection with the study 
drug is minimal. 
 
9.1.6 
Reporting of Adverse Events 
 
All AEs occurring after the start of the study must be recorded until end of follow-up (1y), or 
until subject withdrawal. Subjects entry into the study is defined as the time at which informed 
consent is obtained. All subsequent AEs, irrespective of whether no drug, study drug or 
placebo was administered, must be recorded on specific AE pages of the respective CRF, 
regardless of whether or not they are considered to be study drug related. AEs occurring 
from study drug initiation until 30 days post study drug discontinuation (inclusive) are defined 
as treatment emergent. 
 
9.1.7 
Follow-up of Adverse Events  
 
AEs still ongoing at the follow-up visit must be followed until resolution if possible. 
 
 
9.2 
Serious Adverse Events/Serious Adverse Reaction 
 
9.2.1 
Definitions  
 
9.2.1.1 
Serious Adverse Events/Serious Adverse Reaction (SAE/SAR) 
 
An SAE or SAR is defined by the International Conference on Harmonisation (ICH) 
guidelines as any AE fulfilling at least one of the following criteria: 
• 
Fatal 
• 
Life-threatening 
• 
Requiring subject's hospitalisation or prolongation of existing hospitalisation 
• 
Resulting in persistent or significant disability or incapacity 
• 
Congenital anomaly or birth defect 
• 
Medically significant or requires intervention to prevent at least one of the outcomes 
listed above 
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Life-threatening refers to an event in which the subject was at risk of death at the time of the 
event. It does not refer to an event that hypothetically might have caused death if it were 
more severe. 
Important medical events that may not immediately result in death, be life-threatening or 
require hospitalisation may be considered as SAEs when, based upon appropriate medical 
judgment, they may jeopardise the subject and may require medical or surgical intervention 
to prevent one of the outcomes listed in the definitions above. 
The reference safety document to assess whether or not an SAE should be reported by the 
Sponsor to Health Authorities, Ethics Committees (ECs)/IRBs and Investigators in an 
expedited fashion, is the Investigator's Brochure. 
 
9.2.1.2 
Hospitalisation and Prolongation of Existing Hospitalisation 
 
Hospitalisation is defined as an overnight stay in a hospital unit and/or emergency room. 
An additional overnight stay defines a prolongation of existing hospitalisation. 
The following is not considered an SAE and should be reported as an AE only: 
• 
Treatment on an emergency or outpatient basis for an event not fulfilling the definition 
of seriousness given above and not resulting in hospitalisation 
The following reasons for hospitalisations are not considered AEs and therefore not SAEs: 
• 
Hospitalisations for cosmetic elective surgery, social and/or convenience reasons 
• 
Standard monitoring of a pre-existing disease or medical condition that did not 
worsen, including elective hospitalisation for observation in order to facilitate the 
follow-up when practical and logistical circumstances exist 
• 
Elective treatment of a pre-existing disease or medical condition that did not worsen, 
e.g., hospitalisation for chemotherapy for cancer, elective hip replacement for arthritis 
 
9.2.1.3 
Serious Adverse Events Related to Study-mandated Procedures  
 
SAEs related to study-mandated procedures are defined as SAEs that appear to have a 
reasonable possibility of causal relationship (i.e., a relationship cannot be ruled out) to study-
mandated procedures (excluding administration of study drug) such as discontinuation of 
subject's previous treatment during a washout period or complication of a mandated invasive 
procedure (e.g., blood sampling, heart catheterisation) or car accident on the way to the 
hospital for a study visit, etc. 
 
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9.2.1.4 
Suspected Unexpected Serious Adverse Reaction (SUSAR) 
 
All suspected ARs related to a study drug which occur in the concerned study, and that are 
both unexpected and serious are classified as suspected unexpected serious adverse 
reactions (SUSARs).  
 
9.2.2 
Reporting of Serious Adverse Events  
 
9.2.2.1 
Before Study Drug Initiation 
 
SAEs occurring after signature of the Informed Consent and up to study drug initiation must 
be reported on SAE forms and on the AE pages of the respective CRF. 
 
9.2.2.2 
During Study Drug Administration 
 
All SAEs regardless of causal relationship must be reported, including those related to study-
mandated procedures. These SAEs occurring during study drug administration, i.e., between 
study drug initiation and follow-up after study drug discontinuation (as per Section 9.2.2.3), 
are defined as treatment emergent SAEs. Elective hospitalisation should be considered as 
non-reportable events and should only be recorded as clinical finding. 
 
These SAEs are reported on SAE forms and on the AE pages of the respective CRF.  
 
9.2.2.3 
After Study Drug Discontinuation 
 
All SAEs occurring within and including 30 days after study drug discontinuation must be 
recorded and reported on an SAE form and on the AE pages of the respective CRF. These 
SAEs are defined as treatment emergent. 
SAEs occurring after 30 days post last administration of study drug are reported until end of 
follow-up (1y), or until subject withdrawal (as per section 5.4.2).  
 
9.2.2.4 
Reporting Procedures by the Investigator 
 
All SAEs as defined above must be reported by the Investigator to the CRO’s Drug Safety 
department within 24 hours of the Investigator's knowledge of the event. 
These SAE forms must be faxed to the CRO’s Drug Safety responsible (see contact details 
Page 5). The Investigator must complete the SAE form in English (unless otherwise 
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specified) and assess the relationship to study drug. Such preliminary reports will be followed 
by detailed descriptions that should include copies of hospital case reports, autopsy reports, 
hospital discharge summaries and other documents when requested and applicable. Follow-
up information about a previously reported SAE must also be reported within 24 hours of 
receiving it. The CRO’s Drug Safety department may contact the Investigator to obtain 
further information.  
 
Suspected (considered related to the study drug) and Unexpected (not previously described 
in the reference safety document), SUSARs will be expedited by the CRO to Health 
Authorities, ECs/IRBs, as appropriate.  
 
9.2.3 
Follow-up of Serious Adverse Events  
 
SAEs must be followed until resolution or death, including those still ongoing at the End-of-
Study visit. 
 
9.2.4 
Reporting Procedures by the CRO on behalf of the Sponsor 
 
All SUSARs will be reported to the competent Regulatory Authority concerned and to the 
competent IEC (or IRB) concerned as soon as possible but within a maximum of 15 days 
(fatal or life-threatening SUSARs within a maximum of 7 days) of first knowledge by the CRO 
or Sponsor. 
Relevant follow-up information of fatal or life-threatening SUSARs will be communicated 
subsequently within an additional eight days. 
Once a year throughout the clinical study, a listing of all suspected SARs (expected and 
unexpected) which have occurred and a report on the safety of the participating subjects 
(Annual Safety Report) will be provided to the competent Regulatory Authority and the 
competent IEC (or IRB).  
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10. 
STATISTICAL PROCEDURES 
 
An SAP will be written to provide details of all statistical analyses. The SAP will be finalised 
before database lock and will comprise all methods and tests applied for analysis of the data 
The different study populations defined for endpoint analysis are described below. 
 
10.1 
Study Populations 
 
Populations for the primary and secondary endpoint analyses 
The primary analysis population will be the intent-to-treat (ITT) population, which will consist 
of all randomised subjects according to the randomised treatment assignment. In addition, 
for the efficacy analyses, the per protocol population (PP) will be used. The PP population 
will be a subset of the ITT population and will consist of all randomised subjects, according to 
the randomised treatment assignment, with exclusion of all major protocol violators. 
 
Population for the safety analysis 
The safety population will consist of all subjects who received at least one dose of study 
drug, with treatment assignment designated according to actual treatment received.  
 
Population for the PK analyses 
The PK analyses will be performed on the PK population, which will consist of all subjets who 
have received study drug and for whom the primary PK data are considered to be sufficient 
and interpretable.  
 
10.2 
Statistical and Analytical Plan for Pharmacokinetic Evaluation 
 
For the sparse sampling, descriptive statistics (mean, median, min, max, standard deviation 
and % coefficient of variation (CV)) will be calculated per sampling day and sample collection 
interval. A separate Data Analysis Plan (DAP) will be prepared prior to the population PK 
analysis. 
 
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10.3 
Evaluation of Safety and Tolerability Parameters 
 
All safety parameters (physical examination, vital signs, bleeding, ECG-parameter, 
biochemistry/haematology and ADA evaluations, concomitant medications (including PE 
characteristics) and AEs) will be summarised descriptively by treatment. Quantitative 
variables will be described by n, mean, standard deviation, median, minimum and maximum. 
Qualitative variables will be described by frequency tables containing counts and 
percentages. Additionally, shift tables will be provided for the safety laboratory parameters 
(within, below or above normal range) from pre-study to post-dose. 
The AEs will be coded according to MedDRA and tabulated by system organ class, preferred 
term and lower level term. An AE will be referred to by the treatment and time point after 
which it occurred, i.e. any AE occurring before the dosing will be counted as a baseline AE 
and will be considered as a treatment-emergent AE only if the severity or relation to drug 
changes. 
No formal statistical testing will be performed on the safety data. 
 
10.4 
Determination of Sample Size 
 
For the sample size calculation SAS version 9.2 has been used.  
The primary endpoint of time-to-response of blood markers (defined as time-to-response) is 
monitored in a survival setting. 
 
Sample Size Calculation The time-to-response of blood markers is monitored in a survival 
setting. The primary endpoint time-to-response of blood markers comprises recovery of 
platelets ≥ 150,000/µL. Accrual period is taken as 1.5 years. Zero to time-to-event period is 
set at 30 days. As median time-to-response for the control group we take 6 days (this 
information is calculated based upon Bandarenko et al.28). For the treated group with 
ALX-0081 we assume a 44% risk reduction corresponding to a reduction in median time to 
event of 2.64 days, and ultimately resulting in a time-to-response of 3.36 days. The hazard 
ratio is defined in the SAS code as the hazard of control versus experimental (ALX-0081) 
treatment thus equalling to 6/3.36=1.786. The sample size calculations are performed based 
on a log-rank test, aiming for a power of 80%, tested 1-sided at 2.5% significance level with 
1:1 randomisation. Note that we assume that 15% of subjects would be lost-to-follow-up. The 
latter is justifiable because the active follow-up period only equals 30 days. Based on the 
above described assumptions a sample size of 110 subjects is required. 
 
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10.5 
Assessment of Primary Endpoint 
 
The primary endpoint (i.e. time-to-response of blood markers comprising recovery of 
platelets ≥ 150,000/µL) will be formally assessed by means of a survival analysis. An SAP 
will be prepared before closing the database and will comprise all methods and tests applied 
for analysis of the data. 
Assessment of the primary endpoint is performed by using a one-sided log-rank test at 2.5% 
significance level. A Kaplan-Meier (KM) analysis with time-to-response as the endpoint and 
treatment group as the independent variable, and stratified for absence/presence of one PE 
session prior to randomisation, will be performed on the ITT and PP populations. An 
observation is censored if the observation does not meet the defined time interval of 30 days 
after first administration of study drug medication, due to any cause of loss-to follow-up 
(including death), or endpoint not being reached within the defined time interval. 
The log-rank test is one-sided because inhibition by ALX-0081 of vWF is expected for all 
subjects. Indeed, as described in section 2.4.2, 100% of subjects receiving a SD s.c. 
injection of 8 mg already had inhibition of RICO up to a minimum of 18 hours. 
 
10.6 
Analysis of Efficacy Parameters and Secondary Endpoints 
 
Descriptive statistics for efficacy parameters and secondary endpoints, including PD 
parameters, will be presented for all available data using either the ITT population, the safety 
population, or the PP population. The descriptive statistics will include (but not limited to) the 
number of observations, mean, standard deviation, median, minimum and maximum for 
continuous variables and number of observations and their percentages for categorical 
parameters. An SAP will be prepared before closing the database and will comprise all 
methods and tests applied for analysis of the data. 
 
10.7 
Analysis of Tertiary and Exploratory Endpoints 
 
 
 
 
 
 
 
 
 
 
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11. 
ETHICAL ISSUES AND INSURANCE 
 
11.1 
Independent Ethics Committee 
 
The study protocol (including all substantial amendments) together with the written informed 
consent form and informed consent updates, subject recruitment procedures (e.g. 
advertisements), any other written information to be provided to subjects, and any other 
documents needed by the IEC will be submitted for approval to the IEC which according to 
local regulatory requirements is in charge. Written approval of the study needs to be obtained 
from the IEC prior to the start of the study. 
The Sponsor should submit written reports of the clinical study status to the IEC annually, or 
more frequently if requested by the IEC. A final study notification will be forwarded to the IEC 
within 90 days after the study has been completed or in the event of premature termination of 
the study within 15 days. 
The IEC will be informed of all subsequent protocol amendments and of all SUSARs 
occurring during the study and all other events that have an impact on the safety of the 
subjects or the conduct of the study. 
 
11.2 
Ethical Conduct of the Study 
 
The study will be conducted in accordance with the EU Clinical Trial Directive 2001/20/EC, 
the ICH guideline for GCP dated July 1996 and the ethical principles laid down in the 
Declaration of Helsinki (Appendix 1). Current national regulations and guidelines will also be 
followed. 
 
11.3 
Patient Information and Consent 
 
The subjects or in case that the subject is physically or mentally incapable, their legal 
representatives according to local law will be informed about the nature and importance of 
the study. They will receive a detailed description of the foreseeable risks and discomforts 
and of the procedures to be followed. They will be informed that they are free to withdraw 
from the study at any time without any disadvantages. The consent form must be approved 
(along with the protocol) by the IEC and be acceptable to the Sponsor. The consent form 
must be in a language fully comprehensible to the prospective subject/representative. 
In first intention, voluntary informed consent will be signed and dated by each subject and the 
person who conducted the informed consent discussion at screening prior to any study-
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related procedures.  All subjects will be fully informed about the meaning, aim and conduct of 
the study. This will take place under conditions where the participant has adequate time to 
consider the risks and benefits associated with his participation in the study. The subjects will 
have the possibility to ask all of their questions. By dating and signing the informed consent 
form, the subjects will agree to their participation in the study. 
In second intention, in the expected case where subjects cannot provide informed consent  
due to physical or mental incapacity, a legal representative of the subject will be able to 
provide consent according to local requirements, and regulations and IEC approval. In the 
clinical setting of this trial investigating the acute phase of TTP, this occurrence is expected 
to be more frequent, with a more severe intensity of physical and/or mental incapacity. If 
local requirements, regulations and ethical committees allow, the study can be initiated prior 
to obtaining the informed consent, in case of physical or mental incapacity to consent and 
absence of a legal representative. 
As soon as possible, voluntary informed consent must be sought and obtained from these 
physically or mentally incapacitated subject, or legal representative, as applicable. 
It is the responsibility of the Investigator to assure that informed consent is obtained for each 
participant in accordance with Section 4.8 of the ICH consolidated guideline for GCP from 
July 1996, and local regulations. The signed informed consent will be retained with the study 
records. Each participant will receive a copy of the signed informed consent. 
The Investigator should maintain a log of all subjects who sign the informed consent form 
and indicate if the subject received study drug or, if not, the reason why. The subject’s 
medical records should also document that the informed consent form was signed and dated 
prior to any study-related procedures being performed. 
 
11.4 
Insurance/Liability 
 
All subjects who have given their written consent to the clinical study will be protected in 
accordance with local Law. The policies regarding compensation for injury for subjects are 
described in the compensation information leaflet and are available upon request. A copy of 
the compensation information leaflet will be given to the subject upon request in accordance 
with the country specific requirements. 
 
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12. 
GENERAL 
REGULATIONS, 
AGREEMENTS 
AND 
ORGANISATIONAL PROCEDURES 
 
 
12.1 
Legal Aspects/Declaration of Helsinki 
 
This study follows the Declaration of Helsinki (sixth revision, 2008) (Appendix 1), the 
appropriate local regulations and the ICH-GCP Note for Guidance. 
 
12.2 
Investigator’s Brochure 
 
The Investigator will be informed about current knowledge concerning the study medication 
through the Investigator’s Brochure. Any substantial new information will be provided with no 
delay to all parties concerned. 
 
12.3 
Data Protection 
 
During this clinical study, all clinical data will be identified only through an ID number and the 
subject’s initials. 
The Investigator ensures that the appointed monitor, the project manager, the auditor or 
representatives of the competent authorities and ECs may examine all parts of the 
documentation associated directly with this study (including, but not limited to, laboratory test 
results, admission/discharge reports of hospitalisations during participation in the clinical 
study and autopsy reports for deaths occurring during the clinical study). 
 
12.4 
Monitoring 
 
During the study initiation visit the monitor explains to the Investigator all the documents and 
procedures relating to this study. 
Tight monitoring by the appointed monitor is carried out in order to ensure the study’s high 
quality standards. 
A detailed description of monitoring is defined in the standard operating procedures (SOPs). 
Regular monitoring visits are carried out at appropriate intervals in order to clarify questions 
that may crop up and to review all CRFs in terms of completeness and plausibility. This also 
involves source data verification. 
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The above includes a 100% review of subject numbers, initials, consent forms, demographic 
data, visit data, inclusion/exclusion criteria - as far as possible - as well as all AEs. The 
Investigator has to maintain these data up-to-date and well documented in the medical files. 
Source data verification is done by direct inspection of the original medical files by authorised 
persons. 
Personnel changes at the Investigator’s site and changes in responsibilities must be notified 
by him/her immediately. 
The following is also constantly monitored: the study’s logistic workflow, compliance with 
regulations and the study medication’s handling. 
The monitor is the Investigator’s permanent contact person. Unusual incidents will be 
documented immediately and forwarded to the project director. 
The remaining study medication and the CRFs will be retrieved on the clinical study’s 
completion. 
 
12.5 
Audits and Inspections 
 
In the interests of quality assurance, the Sponsor or appointed independent experts may 
carry out audits during the clinical study’s implementation phase and after its completion. In 
conjunction with the audit it may also be examined whether the planning, implementation and 
analysis of the clinical study meets the relevant statutory regulations and the requirements of 
GCP. This includes a review of data maintenance and organisation at the study site and at 
the Sponsor’s, inspection of equipment and laboratories and of the source documents. 
 
12.6 
Storage of Study Records in the Investigator’s File 
 
The Investigator will be provided with an Investigator’s file. The Investigator will store those 
documents necessary for the clinical study. As part of the monitoring, the Investigator’s file 
will be inspected for up-to-date information and completeness in accordance with the 
national and international regulations. 
The Investigator records in the subject identification log the following details for all persons 
giving their consent to participate in the study: name (first and surname), date of birth, sex, 
subject initials (first and surname) and the assigned subject number. The date of recruitment 
into the study must also be documented. 
This subject identification log serves for later identification and remains with the Investigator. 
After the study’s completion or termination, all study documentation, including the subject 
identification log, will be properly archived in accordance with the Sponsor’s instructions. 
 
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12.7 
Costs 
 
Agreement will be reached between PRA and the Principal Investigator, on incurred costs. 
These relate to the number of subjects recruited for the study plus the costs of control visits 
and other study related procedures. This agreement applies to payment for protocol-
compliant, fully completed and documented subjects. The payment for subjects withdrawing 
from the study prematurely will be paid proportionally. 
 
12.8 
Confidentiality 
 
The objectives and contents of this clinical study as well as its results are to be treated as 
confidential and may not be made accessible to third parties. Employees participating in the 
study are bound by this agreement. 
 
12.9 
The Clinical Study’s Approval and General Obligation of Notification 
 
All documents associated with the study will be submitted to the competent Regulatory 
Authority for approval. 
Additionally all notifications to local authorities as laid down in the relevant national 
regulations will be made. 
The Investigator will receive a copy of the notification for information. 
 
12.10 
Final Report and Publication 
 
An integrated study report in accordance with the ICH Harmonised Tripartite Guideline (E3) 
(Structure and content of clinical study reports) will be prepared. The main clinical study 
report (CSR) will be generated once the last subject has completed the 1-month follow-up 
visit, and will describe the complete data set/results for the primary and secondary endpoints 
of all subjects in the trial. The data set/results on the 12-month follow-up period will be 
included in a longer term (disease outcome) addendum to the CSR. 
 
All data and records provided by the Sponsor or generated during the study (other than 
subject’s medical records) and all data and inventions discovered in the course of conducting 
the study, whether patentable or not, are the sole and exclusive property of the Sponsor.  
The Investigator and all other study team members at any Service Provider involved will 
keep strictly confidential any information provided by the Sponsor related to this study and all 
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data and records generated in the course of the study. They will not use the information, data 
or records for any other purpose than conducting the study without prior written approval of 
the Sponsor. 
 
Publication of any results from this study will be according to the principles of the Declaration 
of Helsinki, in particular point 30, and will require prior written agreement of the Sponsor. 
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13. 
REFERENCES 
 
 1.  Vesely S.K., George J.N., Lammle B. et al. ADAMTS13 activity in thrombotic 
thrombocytopenic purpura-hemolytic uremic syndrome: relation to presenting features 
and clinical outcomes in a prospective cohort of 142 patients. Blood 2003; 102: 60-68. 
 2.  George 
J.N., 
Vesely 
S.K. 
and 
Terrell 
D.R. 
The 
Oklahoma 
Thrombotic 
Thrombocytopenic Purpura-Hemolytic Uremic Syndrome (TTP-HUS) Registry: a 
community perspective of patients with clinically diagnosed TTP-HUS. Semin.Hematol. 
2004; 41: 60-67. 
 3.  Ulrichts Hans and Priem S. Internal report A068-PHA-09-ANP-001: Assessment of in 
vitro potency of ALX-0081 in TTP plasma and verification of matrix effect in bioanalysis 
assays (draft study plan). 7-9-2009. 
 4.  De Buck S. Internal report A001-PHA-08-ISR-002: Plasma pharmacokinetics of 
ALX-0081 in the guinea pig after a single intravenous or subcutaneous administration. 
14-2-2008. 
 5.  Leuschner J. and De Buck S. LPT report 22344: Pharmacokinetic study of ALX-0081 
following single intravenous or subcutaneous administration to guinea pigs. 2008. 
 6.  Silence K. and Dreier T. Report ALX-0081 TR038: Clearance and biodistribution of 
ALX-0081, free or in complex with human vWF, evaluated in mice. 15-12-2006. 
 7.  Laika B., Witschital K. and von Nieciecki A. BioProof report AB-08-01: Acute toxicity for 
ALX-0681 and ALX-0081 after respective single subcutaneous or intravenous 
administration to cynomolgus monkeys (LPT study 22630/1). 14-10-2008. 
 8.  Dreier T. Clinical study report ALX-0081-01/06: A phase I, double-blind, randomized, 
placebo-controlled, parallel group study in healthy male volunteers to investigate the 
safety, tolerability and pharmacokinetics of the Nanobody ALX-0081 administered 
intravenously as single ascending doses. 20-12-2007. 
 9.  Ohri M. Clinical study report ALX-0081-1.2/08: A Phase I, double-blind, randomized, 
placebo-controlled study of ALX-0081 multiple dose administrations in stable angina 
patients undergoing percutaneous coronary intervention (PCI) Draft. 2-7-2009. 
 10.  den Daas I. Clinical study report ALX-0681-1.1/08 A phase I study in healthy volunteers 
to investigate the safety, tolerability, pharmacokinetics and pharmacodynamics of anti-
vWF Nanobody administered subcutaneously. 2-9-2009. 
 11.  Silence K. and Dreier T. Report ALX-0081 TR008: Bleeding risk assessment study with 
ALX-0081 in baboons and comparison with Plavix® and ReoPro®. 11-11-2006. 
 12.  Mannucci P.M. Treatment of von Willebrand's disease. N.Engl.J.Med. 2004; 351: 683-
694. 
 13.  Allford S.L., Hunt B.J., Rose P. and Machin S.J. Guidelines on the diagnosis and 
management of the thrombotic microangiopathic haemolytic anaemias. Br.J.Haematol. 
2003; 120: 556-573. 
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 14.  Sadler J.E., Moake J.L., Miyata T. and George J.N. Recent advances in thrombotic 
thrombocytopenic purpura. Hematology.Am.Soc.Hematol.Educ.Program. 2004; , 407-
423. 
 15.  Martin J.N., Jr., Bailey A.P., Rehberg J.F. et al. Thrombotic thrombocytopenic purpura 
in 166 pregnancies: 1955-2006. Am.J.Obstet.Gynecol. 2008; 199: 98-104. 
 16.  Elliott M.A., Nichols W.L., Jr., Plumhoff E.A. et al. Posttransplantation thrombotic 
thrombocytopenic purpura: a single-center experience and a contemporary review. 
Mayo Clin.Proc. 2003; 78: 421-430. 
 17.  Kremer Hovinga J.A. and Meyer S.C. Current management of thrombotic 
thrombocytopenic purpura. Curr.Opin.Hematol. 2008; 15: 445-450. 
 18.  Fontana S., Hovinga J.A., Studt J.D. et al. Plasma therapy in thrombotic 
thrombocytopenic purpura: review of the literature and the Bern experience in a 
subgroup of patients with severe acquired ADAMTS-13 deficiency. Semin.Hematol. 
2004; 41: 48-59. 
 19.  George J.N. Evaluation and management of patients with thrombotic thrombocytopenic 
purpura. J.Intensive Care Med. 2007; 22: 82-91. 
 20.  Howard M.A., Williams L.A., Terrell D.R. et al. Complications of plasma exchange in 
patients treated for clinically suspected thrombotic thrombocytopenic purpura-hemolytic 
uremic syndrome. Transfusion 2006; 46: 154-156. 
 21.  Rizvi M.A., Vesely S.K., George J.N. et al. Complications of plasma exchange in 71 
consecutive patients treated for clinically suspected thrombotic thrombocytopenic 
purpura-hemolytic-uremic syndrome. Transfusion 2000; 40: 896-901. 
 22.  Nguyen L., Terrell D.R., Duvall D., Vesely S.K. and George J.N. Complications of 
plasma exchange in patients treated for thrombotic thrombocytopenic purpura. IV. An 
additional study of 43 consecutive patients, 2005 to 2008. Transfusion 2009; 49: 392-
394. 
 23.  Lammle B., Kremer Hovinga J.A. and Alberio L. Thrombotic thrombocytopenic purpura. 
J.Thromb.Haemost. 2005; 3: 1663-1675. 
 24.  Lewis Q.F., Lanneau M.S., Mathias S.D. et al. Long-term deficits in health-related 
quality of life after recovery from thrombotic thrombocytopenic purpura. Transfusion 
2009; 49: 118-124. 
 25.  Galbusera M., Benigni A., Paris S. et al. Unrecognized pattern of von Willebrand factor 
abnormalities in hemolytic uremic syndrome and thrombotic thrombocytopenic purpura. 
J.Am.Soc.Nephrol. 1999; 10: 1234-1241. 
 26.  Remuzzi G., Galbusera M., Noris M. et al. von Willebrand factor cleaving protease 
(ADAMTS13) is deficient in recurrent and familial thrombotic thrombocytopenic purpura 
and hemolytic uremic syndrome. Blood 2002; 100: 778-785. 
 27.  Page L.K., Psaila B., Provan D. et al. The immune thrombocytopenic purpura (ITP) 
bleeding score: assessment of bleeding in patients with ITP. Br.J.Haematol. 2007; 138: 
245-248. 
 28.  Bandarenko N., Brecher M.E. and Members of the US TT Apheresis Study Group. 
United States Thrombotic Thrombocytopenic Purpura Apheresis Study group (US TTP 
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ASG): Multicenter survey and retrospective analysis of current efficacy of therapeutics 
plasma exchange. Journal of Clinical Apheresis 1998; 13: 133-141. 
 
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14. 
APPENDICES 
 
14.1 
Appendix 1: 
Declaration of Helsinki 
 
WORLD MEDICAL ASSOCIATION DECLARATION OF HELSINKI (Sixth revision, 2008) 
 
Ethical Principles for Medical Research Involving Human Subjects  
Adopted by the 18th WMA General Assembly, Helsinki, Finland, June 1964, and amended 
by the 
29th WMA General Assembly, Tokyo, Japan, October 1975 
35th WMA General Assembly, Venice, Italy, October 1983 
41st WMA General Assembly, Hong Kong, September 1989 
48th WMA General Assembly, Somerset West, Republic of South Africa, October 1996 and 
the 52nd WMA General Assembly, Edinburgh, Scotland, October 2000  
53th WMA General Assembly, Washington 2002 (Note of Clarification on Paragraph 29 
added) 
55th WMA General Assembly, Tokyo 2004 (Note of Clarification on Paragraph 30 added)  
59th WMA General Assembly, Seoul, October 2008  
A. 
INTRODUCTION  
1. The World Medical Association (WMA) has developed the Declaration of Helsinki as a 
statement of ethical principles for medical research involving human subjects, 
including research on identifiable human material and data.  
The Declaration is intended to be read as a whole and each of its constituent 
paragraphs should not be applied without consideration of all other relevant 
paragraphs. 
2. Although the Declaration is addressed primarily to physicians, the WMA encourages 
other participants in medical research involving human subjects to adopt these 
principles. 
3. It is the duty of the physician to promote and safeguard the health of patients, 
including those who are involved in medical research. The physician's knowledge and 
conscience are dedicated to the fulfilment of this duty. 
4. The Declaration of Geneva of the WMA binds the physician with the words, "The 
health of my patient will be my first consideration," and the International Code of 
Medical Ethics declares that, "A physician shall act in the patient's best interest when 
providing medical care." 
5. Medical progress is based on research that ultimately must include studies involving 
human subjects. Populations that are underrepresented in medical research should 
be provided appropriate access to participation in research. 
6. In medical research involving human subjects, the well-being of the individual 
research subject must take precedence over all other interests. 
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7. The primary purpose of medical research involving human subjects is to understand 
the causes, development and effects of diseases and improve preventive, diagnostic 
and therapeutic interventions (methods, procedures and treatments). Even the best 
current interventions must be evaluated continually through research for their safety, 
effectiveness, efficiency, accessibility and quality. 
8. In medical practice and in medical research, most interventions involve risks and 
burdens. 
9. Medical research is subject to ethical standards that promote respect for all human 
subjects and protect their health and rights. Some research populations are 
particularly vulnerable and need special protection. These include those who cannot 
give or refuse consent for themselves and those who may be vulnerable to coercion 
or undue influence. 
10. Physicians should consider the ethical, legal and regulatory norms and standards for 
research involving human subjects in their own countries as well as applicable 
international norms and standards. No national or international ethical, legal or 
regulatory requirement should reduce or eliminate any of the protections for research 
subjects set forth in this Declaration. 
B. BASIC PRINCIPLES FOR ALL MEDICAL RESEARCH  
11. It is the duty of physicians who participate in medical research to protect the life, 
health, dignity, integrity, right to self-determination, privacy, and confidentiality of 
personal information of research subjects. 
12. Medical research involving human subjects must conform to generally accepted 
scientific principles, be based on a thorough knowledge of the scientific literature, 
other relevant sources of information, and adequate laboratory and, as appropriate, 
animal experimentation. The welfare of animals used for research must be respected.  
13. Appropriate caution must be exercised in the conduct of medical research that may 
harm the environment. 
14. The design and performance of each research study involving human subjects must 
be clearly described in a research protocol. The protocol should contain a statement 
of the ethical considerations involved and should indicate how the principles in this 
Declaration have been addressed. The protocol should include information regarding 
funding, sponsors, institutional affiliations, other potential conflicts of interest, 
incentives for subjects and provisions for treating and/or compensating subjects who 
are harmed as a consequence of participation in the research study. The protocol 
should describe arrangements for post-study access by study subjects to 
interventions identified as beneficial in the study or access to other appropriate care or 
benefits. 
15. The research protocol must be submitted for consideration, comment, guidance and 
approval to a research ethics committee before the study begins. This committee 
must be independent of the researcher, the sponsor and any other undue influence. It 
must take into consideration the laws and regulations of the country or countries in 
which the research is to be performed as well as applicable international norms and 
standards but these must not be allowed to reduce or eliminate any of the protections 
for research subjects set forth in this Declaration. The committee must have the right 
to monitor ongoing studies. The researcher must provide monitoring information to the 
committee, especially information about any serious adverse events. No change to 
the protocol may be made without consideration and approval by the committee. 
16. Medical research involving human subjects must be conducted only by individuals 
with the appropriate scientific training and qualifications. Research on patients or 
healthy volunteers requires the supervision of a competent and appropriately qualified 
physician or other health care professional. The responsibility for the protection of 
research subjects must always rest with the physician or other health care 
professional and never the research subjects, even though they have given consent. 
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17. Medical research involving a disadvantaged or vulnerable population or community is 
only justified if the research is responsive to the health needs and priorities of this 
population or community and if there is a reasonable likelihood that this population or 
community stands to benefit from the results of the research. 
18. Every medical research study involving human subjects must be preceded by careful 
assessment of predictable risks and burdens to the individuals and communities 
involved in the research in comparison with foreseeable benefits to them and to other 
individuals or communities affected by the condition under investigation. 
19. Every clinical trial must be registered in a publicly accessible database before 
recruitment of the first subject. 
20. Physicians may not participate in a research study involving human subjects unless 
they are confident that the risks involved have been adequately assessed and can be 
satisfactorily managed. Physicians must immediately stop a study when the risks are 
found to outweigh the potential benefits or when there is conclusive proof of positive 
and beneficial results. 
21. Medical research involving human subjects may only be conducted if the importance 
of the objective outweighs the inherent risks and burdens to the research subjects. 
22. Participation by competent individuals as subjects in medical research must be 
voluntary. Although it may be appropriate to consult family members or community 
leaders, no competent individual may be enrolled in a research study unless he or she 
freely agrees. 
23. Every precaution must be taken to protect the privacy of research subjects and the 
confidentiality of their personal information and to minimize the impact of the study on 
their physical, mental and social integrity. 
24. In medical research involving competent human subjects, each potential subject must 
be adequately informed of the aims, methods, sources of funding, any possible 
conflicts of interest, institutional affiliations of the researcher, the anticipated benefits 
and potential risks of the study and the discomfort it may entail, and any other relevant 
aspects of the study. The potential subject must be informed of the right to refuse to 
participate in the study or to withdraw consent to participate at any time without 
reprisal. Special attention should be given to the specific information needs of 
individual potential subjects as well as to the methods used to deliver the information. 
After ensuring that the potential subject has understood the information, the physician 
or another appropriately qualified individual must then seek the potential subject's 
freely-given informed consent, preferably in writing. If the consent cannot be 
expressed in writing, the non-written consent must be formally documented and 
witnessed. 
25. For medical research using identifiable human material or data, physicians must 
normally seek consent for the collection, analysis, storage and/or reuse. There may 
be situations where consent would be impossible or impractical to obtain for such 
research or would pose a threat to the validity of the research. In such situations the 
research may be done only after consideration and approval of a research ethics 
committee. 
26. When seeking informed consent for participation in a research study the physician 
should be particularly cautious if the potential subject is in a dependent relationship 
with the physician or may consent under duress. In such situations the informed 
consent should be sought by an appropriately qualified individual who is completely 
independent of this relationship. 
27. For a potential research subject who is incompetent, the physician must seek 
informed consent from the legally authorized representative. These individuals must 
not be included in a research study that has no likelihood of benefit for them unless it 
is intended to promote the health of the population represented by the potential 
subject, the research cannot instead be performed with competent persons, and the 
research entails only minimal risk and minimal burden. 
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28. When a potential research subject who is deemed incompetent is able to give assent 
to decisions about participation in research, the physician must seek that assent in 
addition to the consent of the legally authorized representative. The potential subject's 
dissent should be respected. 
29. Research involving subjects who are physically or mentally incapable of giving 
consent, for example, unconscious patients, may be done only if the physical or 
mental condition that prevents giving informed consent is a necessary characteristic of 
the research population. In such circumstances the physician should seek informed 
consent from the legally authorized representative. If no such representative is 
available and if the research cannot be delayed, the study may proceed without 
informed consent provided that the specific reasons for involving subjects with a 
condition that renders them unable to give informed consent have been stated in the 
research protocol and the study has been approved by a research ethics committee. 
Consent to remain in the research should be obtained as soon as possible from the 
subject or a legally authorized representative. 
30. Authors, editors and publishers all have ethical obligations with regard to the 
publication of the results of research. Authors have a duty to make publicly available 
the results of their research on human subjects and are accountable for the 
completeness and accuracy of their reports. They should adhere to accepted 
guidelines for ethical reporting. Negative and inconclusive as well as positive results 
should be published or otherwise made publicly available. Sources of funding, 
institutional affiliations and conflicts of interest should be declared in the publication. 
Reports of research not in accordance with the principles of this Declaration should 
not be accepted for publication. 
C. ADDITIONAL PRINCIPLES FOR MEDICAL RESEARCH COMBINED WITH 
MEDICAL CARE 
31. The physician may combine medical research with medical care only to the extent that 
the research is justified by its potential preventive, diagnostic or therapeutic value and 
if the physician has good reason to believe that participation in the research study will 
not adversely affect the health of the patients who serve as research subjects. 
32. The benefits, risks, burdens and effectiveness of a new intervention must be tested 
against those of the best current proven intervention, except in the following 
circumstances: 
• 
The use of placebo, or no treatment, is acceptable in studies where no current proven 
intervention exists; or  
• 
Where for compelling and scientifically sound methodological reasons the use of 
placebo is necessary to determine the efficacy or safety of an intervention and the 
patients who receive placebo or no treatment will not be subject to any risk of serious 
or irreversible harm. Extreme care must be taken to avoid abuse of this option. 
33. At the conclusion of the study, patients entered into the study are entitled to be 
informed about the outcome of the study and to share any benefits that result from it, 
for example, access to interventions identified as beneficial in the study or to other 
appropriate care or benefits. 
34. The physician must fully inform the patient which aspects of the care are related to the 
research. The refusal of a patient to participate in a study or the patient's decision to 
withdraw from the study must never interfere with the patient-physician relationship. 
35. In the treatment of a patient, where proven interventions do not exist or have been 
ineffective, the physician, after seeking expert advice, with informed consent from the 
patient or a legally authorized representative, may use an unproven intervention if in 
the physician's judgement it offers hope of saving life, re-establishing health or 
alleviating suffering. Where possible, this intervention should be made the object of 
research, designed to evaluate its safety and efficacy. In all cases, new information 
should be recorded and, where appropriate, made publicly available. 
22.10.2008 
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14.2 
Appendix 2: 
Common Terminology for Adverse Events v4.0 
(CTCAE) 
 
National Cancer Institute (NCI) CTCAE Version 4.0 
See http://ctep.cancer.gov/reporting/ctc.html. 
 
14.3 
Appendix 3: 
Elements of Informed Consent 
 
The following elements of Informed Consent are compatible with the ICH, GCP and country-
specific regulations. The Informed Consent Form should address each issue listed. 
 
1. 
The trial involves research. 
2. 
The purpose of the trial. 
3. 
The trial treatment(s) and the probability for random assignment to each treatment. 
4. 
The trial procedures to be followed, including all invasive procedures. 
5. 
The subject’s responsibilities. 
6. 
Those aspects of the trial that are experimental. 
7. 
The reasonably foreseeable risks or inconveniences to the subject and, when applicable, to an 
embryo, foetus, or nursing infant. 
8. 
The reasonably expected benefits. When there is no intended clinical benefit to the subject, the 
subject should be made aware of this. 
9. 
The alternative procedure(s) or course(s) of treatment that may be available to the subject, and 
their important benefits and risks. 
10. The compensation and/or treatment available to the subject in the event of a trial-related injury. 
11. The anticipated prorated payment, if any, to the subject for participating in the trial. 
12. The anticipated expenses, if any, to the subject for participating in the trial. 
13. The subject’s participation in the trial is voluntary and that the subject may refuse to participate or 
withdraw from the trial, at any time, without penalty or loss of benefits to which the subject is 
otherwise entitled. 
14. The monitors, the auditors, the IRB/IEC and the regulatory authorities will be granted direct 
access to the subject’s original medical records for verification of clinical trial procedures and/or 
data, without violating the confidentiality of the subject, to the extent permitted by applicable laws 
and regulations and that, by signing an ICF, the subject or the subject’s legally acceptable 
representatives authorise such access. 
15. Records identifying the subject will be kept confidential and, to the extent permitted by the 
applicable laws and/or regulations, will not be made publicly available. If the results of the trial are 
published, the subject’s identity will remain confidential. 
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16. The subject or the subject’s legally acceptable representative will be informed in a timely manner 
if information becomes available that may be relevant to the subject’s willingness to continue 
participation in the trial. 
17. The person(s) to contact for further information regarding the trial and the rights of trial subjects, 
and whom to contact in the event of trial-related injury. 
18. The foreseeable circumstances and/or reasons under which the subject’s participation in the trial 
may be terminated. 
19. The expected duration of the subject’s participation in the trial. 
20. The approximate number of subjects involved in the trial. 
 
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Signature Page 
This is a representation of an electronic record that was signed electronically in Livelink. 
This page is the manifestation of the electronic signature(s) used in compliance with the organizations 
electronic signature policies and procedures. 
 
Date: Monday, 08 July 2013, 10:51   Romance Daylight Time 
Meaning: Approved 
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