A Phase 1, Randomized, 2-Period, 2-Sequence, Cross-over Study to Determine the Effect of ALXN1840 on the Metabolism of a CYP2B6 Substrate in Healthy Participants
Phase: PHASE1
Conditions: Wilson Disease
Sponsor: Alexion Pharmaceuticals, Inc.

A Phase 1, Randomized, 2-Period, 2-Sequence, Cross-over Study to 
Determine the Effect of ALXN1840 on the Metabolism of a CYP2B6 
Substrate in Healthy Participants 
Unique Protocol ID: 
NCT Number: 
EudraCT Number:  
Date of Protocol:  
ALXN1840-HV-103 
NCT04526210 
N/A
16 March 2021 

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TITLE PAGE 
Protocol Title: A Phase 1, Randomized, 2-Period, 2-Sequence, Cross-over Study to Determine 
the Effect of ALXN1840 on the Metabolism of a CYP2B6 Substrate in Healthy Participants 
Protocol Number: ALXN1840-HV-103 
Amendment Number: 1 
Compound: ALXN1840 (bis choline tetrathiomolybdate) 
Study Phase: 1 
Short Title: Phase 1 Study of ALXN1840 on the Metabolism of a CYP2B6 Substrate in Healthy 
Participants 
Sponsor Name: Alexion Pharmaceuticals, Inc. 
Legal Registered Address:  
121 Seaport Boulevard 
Boston, MA 02210 
USA 
Regulatory Agency Identifier Number(s) 
IND: 119,006 
Approval Date:  
Original Protocol 
28 Apr 2020 
Amendment 1 
16 Mar 2021 
 
Sponsor Signatory: 
Senior Director 
Clinical Development Sciences
 
Date 
 
Medical Monitor Name and Contact Information can be found in the Study Contact List. 
 
PPD
PPD

PPD
PPD

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PROTOCOL AMENDMENT SUMMARY OF CHANGES TABLE 
DOCUMENT HISTORY 
Document 
Date 
Original Document 
28 Apr 2020 
Amendment 1 
16 Mar 2021 
 
Amendment 1 (16 Mar 2021)  
Overall Rationale for the Amendment: 
The protocol is being amended to increase the number of participants planned for randomization 
in the study from approximately 38 participants to approximately 52. A power outage due to 
extreme and unexpected inclement weather at the clinical research unit (CRU) during study 
conduct resulted in temperature excursion for many on-site pharmacokinetic (PK) samples. As a 
result, PK samples for 17 participants have been anticipated to be unviable pending further 
investigation and additional participants must be enrolled and randomized to ensure completion 
of at least 32 participants. This amendment will also incorporate all changes/clarifications 
previously approved in Protocol Administrative Change Letters 1 and 2, and minor updates to 
formatting and wording for clarity. 

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Section # and Name 
Description of Change 
Brief rationale and/or clarifications 
Substantial Revision 
Synopsis Number of 
Participants  
Synopsis Intervention 
Groups and Duration 
(sequence table) 
Section 4.1 Overall Design 
(text and Table 3) 
Section 9.2 Sample Size 
Determination 
 
Increased the number of 
participants enrolled and 
subsequently randomized in 
the study from approximately 
38 to approximately 52, and 
to the number of participants. 
Additional participants must be 
enrolled and randomized to reach the 
necessary sample size of 32 completed 
participants because PK samples for 
17 participants are anticipated 
unviable. 
the number of participants because the 
defines the Enrolled Set as all 
participants who sign the ICF. Only 
randomized participants, not screen 
failures, should be included in the 
participant numbers planned in this 
protocol amendment. 
Minor Revisions/Clarifications per Administrative Change Letter 1 dated 28 Apr 2020 
Section 9.4.3.1 
Pharmacokinetic and 
Pharmacodynamic Analyses 
 
Note added after the PK 
sampling times to clarify that 
the 336 hours sample in 
Period 1 will be collected 
during the Period 2, Pre-dose 
(Day 1) Visit.  
To clarify that there is no unique 
336 hours sample collection in 
Period 1; it is the same as the sample to 
be collected during the Period 2, 
Pre-dose Visit.  
Section 1.3 Schedule of 
Activities 
will be collected for the serum
sample retained for safety. 
12 mL was determined sufficient for 
this sample. 
Section 10.2 Appendix 2: 
Clinical Laboratory Tests  
Footnote added to Table 7 
(Protocol Required Safety 
Laboratory Assessment) for 
clarification. 
To clarify that only HBsAg testing is 
necessary for exclusion of active HBV 
infection; anti-HBC laboratory 
collection is not required.  
Minor Revisions/Clarifications per Administrative Change Letter 2 dated 09 Sep 2020 
Synopsis Intervention 
Groups and Duration 
(sequence table) 
Section 4.1 Overall Design 
Section 6.3 Measures to 
Minimize Bias: 
Randomization and Blinding 
Removed the 60%:40% 
male/female ratio 
requirement for participant 
enrollment. 
The CRU has had difficulty recruiting 
female subjects for the study, 
potentially due to COVID-19. The 
sponsor determined that removal of a 
specific sex ratio for participants 
would not affect the scientific validity 
of the study. 

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Section 8.5. 
Pharmacokinetics  
Sample collection window 
statement changed from 
ected within 
± 10% of the scheduled time, 
or 30 minutes whichever is 
less, will not be considered a 
 
To ensure samples collected within the 
first 4 hours after dosing are collected 
within 10% of the scheduled collection 
time, which is less than 30 minutes.  
 

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TABLE OF CONTENTS 
TITLE PAGE ...................................................................................................................................1 
 ...............................................................................................2 
PROTOCOL AMENDMENT SUMMARY OF CHANGES TABLE ............................................3 
TABLE OF CONTENTS .................................................................................................................6 
LIST OF TABLES ...........................................................................................................................9 
LIST OF FIGURES .........................................................................................................................9 
1. 
PROTOCOL SUMMARY ..........................................................................................10 
1.1. 
Synopsis ......................................................................................................................10 
1.2. 
Schema ........................................................................................................................13 
1.3. 
Schedule of Activities .................................................................................................14 
2. 
INTRODUCTION ......................................................................................................17 
2.1. 
Study Rationale ...........................................................................................................17 
2.2. 
Background .................................................................................................................19 
2.3. 
Benefit/Risk Assessment ............................................................................................19 
2.3.1. 
Risk Assessment .........................................................................................................19 
2.3.2. 
Benefit Assessment .....................................................................................................20 
2.3.3. 
Overall Benefit: Risk Conclusion ...............................................................................20 
3. 
OBJECTIVES AND ENDPOINTS ............................................................................21 
4. 
STUDY DESIGN .......................................................................................................22 
4.1. 
Overall Design ............................................................................................................22 
4.2. 
Scientific Rationale for Study Design ........................................................................23 
4.3. 
Justification for Dose ..................................................................................................23 
4.4. 
End of Study Definition ..............................................................................................25 
5. 
STUDY POPULATION .............................................................................................26 
5.1. 
Inclusion Criteria ........................................................................................................26 
5.2. 
Exclusion Criteria .......................................................................................................27 
5.3. 
Lifestyle Considerations .............................................................................................29 
5.4. 
Screen Failures ............................................................................................................31 
6. 
STUDY INTERVENTION ........................................................................................32 
6.1. 
Study Intervention Administered ................................................................................32 
6.2. 
Preparation/Handling/Storage/Accountability ............................................................32 

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6.3. 
Measures to Minimize Bias: Randomization and Blinding ........................................33 
6.4. 
Study Intervention Compliance ..................................................................................33 
6.5. 
Concomitant Therapy .................................................................................................34 
6.5.1. 
Allowed Medicine and Therapy .................................................................................34 
6.5.2. 
Disallowed Medicine and Therapy .............................................................................34 
6.6. 
Dose Modification ......................................................................................................34 
6.7. 
Intervention After the End of the Study .....................................................................35 
7. 
DISCONTINUATION OF STUDY INTERVENTION AND 
PARTICIPANT DISCONTINUATION/WITHDRAWAL .......................................36 
7.1. 
Discontinuation of Study Intervention........................................................................36 
7.2. 
Participant Discontinuation/Withdrawal From the Study ...........................................36 
7.3. 
Lost to Follow-up .......................................................................................................37 
8. 
STUDY ASSESSMENTS AND PROCEDURES ......................................................38 
8.1. 
Efficacy Assessments .................................................................................................38 
8.2. 
Safety Assessments .....................................................................................................38 
8.2.1. 
Physical Examinations ................................................................................................38 
8.2.2. 
Vital Signs ..................................................................................................................39 
8.2.3. 
Vital signs will be measured in a semi-supine position after 5 minutes rest. 
Electrocardiograms .....................................................................................................39 
8.2.4. 
Clinical Safety Laboratory Assessments ....................................................................39 
8.2.5. 
Suicidal Ideation and Behavior Risk Monitoring .......................................................40 
8.2.6. 
Pregnancy ...................................................................................................................40 
8.3. 
Adverse Events and Serious Adverse Events .............................................................40 
8.3.1. 
Time Period and Frequency for Collecting Adverse Event and Serious 
Adverse Event Information .........................................................................................41 
8.3.2. 
Method of Detecting AEs and SAEs ..........................................................................41 
8.3.3. 
Follow-up of AEs and SAEs .......................................................................................41 
8.3.4. 
Regulatory Reporting Requirements for SAEs ...........................................................41 
8.3.5. 
Adverse Events of Special Interest .............................................................................42 
8.3.6. 
Retained and Biobanked Sample ................................................................................42 
8.4. 
Treatment of Overdose ...............................................................................................42 
8.5. 
Pharmacokinetics ........................................................................................................42 
8.6. 
Pharmacodynamics .....................................................................................................43 

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8.7. 
Genetics ......................................................................................................................43 
8.8. 
Biomarkers ..................................................................................................................43 
8.9. 
Immunogenicity ..........................................................................................................43 
8.10. 
Health Economics and Medical Resource Utilization ................................................43 
9. 
STATISTICAL CONSIDERATIONS .......................................................................44 
9.1. 
Statistical Hypotheses .................................................................................................44 
9.2. 
Sample Size Determination ........................................................................................44 
9.3. 
Populations for Analyses ............................................................................................44 
9.4. 
Statistical Analyses .....................................................................................................45 
9.4.1. 
Efficacy Analyses .......................................................................................................45 
9.4.2. 
Safety Analyses ..........................................................................................................45 
9.4.3. 
Other Analyses ............................................................................................................46 
9.4.3.1. 
Pharmacokinetic and Pharmacodynamic Analyses ....................................................46 
9.5. 
Interim Analyses .........................................................................................................47 
9.6. 
Data Monitoring Committee .......................................................................................47 
9.7. 
Safety Review Committee ..........................................................................................47 
10. 
SUPPORTING DOCUMENTATION AND OPERATIONAL 
CONSIDERATIONS ..................................................................................................49 
10.1. 
Appendix 1: Regulatory, Ethical, and Study Oversight Considerations ....................49 
10.1.1. 
Regulatory and Ethical Considerations ......................................................................49 
10.1.2. 
Financial Disclosure ...................................................................................................49 
10.1.3. 
Informed Consent Process ..........................................................................................50 
10.1.4. 
Data Protection ...........................................................................................................50 
10.1.5. 
Dissemination of Clinical Study Data ........................................................................51 
10.1.6. 
Data Quality Assurance ..............................................................................................51 
10.1.7. 
Source Documents ......................................................................................................52 
10.1.8. 
Study and Site Start and Closure ................................................................................52 
10.1.9. 
Publication Policy .......................................................................................................52 
10.2. 
Appendix 2: Clinical Laboratory Tests .......................................................................54 
10.3. 
Appendix 3: Adverse Events: Definitions and Procedures for Recording, 
Evaluating, Follow-up, and Reporting ........................................................................56 
10.3.1. 
Definition of AE .........................................................................................................56 
10.3.2. 
Definition of SAE .......................................................................................................56 

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10.3.3. 
Recording and Follow-Up of AE and/or SAE ............................................................57 
10.3.4. 
Reporting of SAEs ......................................................................................................59 
10.4. 
Appendix 4: Contraceptive Guidance and Collection of Pregnancy 
Information .................................................................................................................60 
10.5. 
Appendix 5: Abbreviations .........................................................................................62 
10.6. 
Appendix 6: Protocol Amendment History ................................................................65 
11. 
REFERENCES ...........................................................................................................66 
LIST OF TABLES 
Table 1: 
 Schedule of Activities ................................................................................................14 
Table 2:  
Potential Risks and Mitigation Strategy .....................................................................19 
Table 3: 
Study Design ...............................................................................................................23 
Table 4: 
Healthy Participant Lifestyle Considerations .............................................................29 
Table 5: 
Details of Study Interventions Administered .............................................................32 
Table 6: 
Populations for Analyses ............................................................................................45 
Table 7: 
Protocol-Required Safety Laboratory Assessments ...................................................54 
Table 8: 
List of Abbreviations and Definitions of Terms .........................................................62 
LIST OF FIGURES 
Figure 1: 
Study ALXN1840-HV-103 Schematic .......................................................................13 
 

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1. 
PROTOCOL SUMMARY 
1.1. 
Synopsis 
Protocol Title: A Phase 1, Randomized, 2-Period, 2-Sequence, Cross-over Study to Determine 
the Effect of ALXN1840 on the Metabolism of a CYP2B6 Substrate in Healthy Participants. 
Short Title: Phase 1 Study of ALXN1840 on the Metabolism of a CYP2B6 Substrate in Healthy 
Participants. 
Rationale:  
ALXN1840 is considered to have potential for weak to moderate drug-drug interactions (DDI) 
due to inhibition of cytochrome P450 2B6 (CYP2B6) according to in vitro studies using human 
liver microsomes and simulations performed to assess the potential for DDI risks. This study has 
been designed to determine the effect of ALXN1840 enteric-coated (EC) tablets at a single dose 
of 60 mg (4 × 15 mg), on the metabolism of bupropion (bupropion hydrochloride [HCl],  
WELLBUTRIN SR), a sensitive CYP2B6 substrate, at a single dose of 150 mg. A single dose of 
60 mg ALXN1840 as a perpetrator is considered appropriate due to lack of potential for time-
dependent inhibition (TDI) under the maximum observed ALXN1840 concentration in plasma 
after repeated daily dosing at steady state. A single dose of 150 mg bupropion is considered 
appropriate due to its linear pharmacokinetics (PK) within the approved therapeutic dose range.  
The 60 mg dose of ALXN1840 is the maximum allowed daily dose in the on-going Phase 3 
Study WTX101-301 in patients with Wilson disease (WD). The 150 mg bupropion single dose 
has been selected based on  the WELLBUTRIN SR United States Prescribing Information 
(USPI) (WELLBUTRIN SR) as it has limited safety concerns (such as seizure).  

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Objectives and Endpoints 
Objectives 
Endpoints 
Primary 
 
 
To determine the effect of ALXN1840 on the 
PK of bupropion, a sensitive CYP2B6 
substrate 
 
PK parameters of bupropion (maximum 
observed plasma concentration [Cmax], area 
under the plasma concentration (AUC) versus 
time curve from time 0 to the last quantifiable 
concentration [AUCt], and AUC versus time 
curve from time 0 to infinity [AUC ]) with 
and without the coadministration of 
ALXN1840 
Secondary 
 
 
To determine the effect of ALXN1840 on the 
PK of hydroxybupropion, the major active 
metabolite of bupropion 
 
To determine the effect of ALXN1840 on the 
PK of plasma molybdenum (Mo) with the 
coadministration of bupropion 
 
To determine the safety and tolerability of 
ALXN1840, with the coadministration of 
bupropion  
 
PK parameters of hydroxybupropion (Cmax, 
AUCt, and AUC ) with and without the 
coadministration of ALXN1840 
 
PK parameters for plasma total Mo (Cmax, 
AUCt, and AUC ) with the coadministration 
of bupropion 
 
Safety assessed by incidence of 
treatment-emergent adverse events (TEAEs) 
and treatment-emergent serious adverse 
events (TESAEs), physical examination, vital 
signs measurements, clinical laboratory and 
12-lead electrocardiogram (ECG) results  
Abbreviations: AUC  = area under the plasma concentration versus time curve from time 0 to infinity; AUCt = area 
under the plasma concentration versus time curve from time 0 to the  last quantifiable  concentration; 
Cmax = maximum observed plasma concentration of the drug; CYP2B6 = Cytochrome P450 2B6; 
ECG = electrocardiogram; Mo = molybdenum; PK = pharmacokinetics; TEAE = treatment-emergent adverse event; 
TESAE = treatment-emergent serious adverse event 
Overall Design 
This is a Phase 1, randomized, 2-period, 2-sequence, cross-over study designed to determine the 
effect of ALXN1840 on the metabolism of bupropion, a sensitive CYP2B6 substrate, in healthy 
male and female participants. The safety and tolerability of ALXN1840 will be determined along 
with ALXN1840 PK in plasma as measured via total Mo with the coadministration of bupropion.  
Disclosure Statement: This is an open-label, 2-period, 2-sequence, cross-over study in healthy 
participants with randomization to 2 treatment sequences. 
Number of Participants: 
It is planned that approximately 52 participants will be enrolled and randomized at a single site. 
Intervention Groups and Duration: 
The study has a Screening Period (Day -28 to Day -2), two 11-day study periods (Day 1 to 
Day 11) with a minimum of 14 days between doses of bupropion, and an End of Study (EOS) 
Visit (Day 15 ± 2 days) after Period 2 dosing. Participants will report to the CRU on the day 
prior (Day -1) to both dosing periods. 
In each study period, participants will receive one of the 2 treatments noted below:  

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 Treatment A: One 150 mg bupropion HCl salt tablet (WELLBUTRIN SR 150) with 
240 mL water (fasting). 
 Treatment B: One 150 mg bupropion HCl salt tablet (WELLBUTRIN SR 150) 
+ 4 × 15 mg ALXN1840 EC tablets with 240 mL water (fasting). 
Participants will receive each treatment as a single dose administration in the sequence as 
defined below. 
Sequence number 
Treatment sequence 
Total 
Study Period 1 
Study Period 2 
1 
A 
B 
26 
2 
B 
A 
26 
Total 
52 
Treatment A -One 150 mg bupropion HCl salt tablet (WELLBUTRIN SR 150) with 240 mL water (fasting) 
Treatment B  One 150 mg bupropion HCl salt tablet (WELLBUTRIN SR 150) + 4 × 15 mg ALXN1840 
enteric-coated tablets with 240 mL water (fasting) 
The time between dosing bupropion alone or in combination with ALXN1840 in each treatment 
sequence will be a minimum of 14 days. Based on the estimated mean ALXN1840 half-life of 
approximately 2 days in healthy participants (under oral dose of 60 mg), a 14-day period 
between doses of bupropion is considered sufficient to eliminate, on average, approximately 
more than 99.2% of the plasma total Mo before the next dose of bupropion is administered. The 
mean elimination half-life (±SD) of bupropion after chronic dosing is 21 (± 9) hours 
(WELLBUTRIN SR). A 14-day period between doses of bupropion is sufficient to eliminate, on 
average, more than 99.2% of the plasma bupropion before the next dose of bupropion is 
administered.  
Participants will return to the CRU on Day 15 (± 2 days) following Period 2 dosing for the EOS 
Visit with follow-up procedures, and to determine if any adverse events (AEs) have occurred 
since the last study visit. If participants withdraw from the study early, they will be seen and 
assessed by the Principal Investigator, and whenever possible, they are to undergo the procedures 
associated with the EOS Visit. Participants may be replaced at the discretion of Alexion. 
Participants may be asked or required to stay in the CRU between Periods 1 and 2, and/or before 
the EOS visit, for their own safety, and also to maintain the integrity of the conduct of the study. 
Data Monitoring Committee:  
There will not be a Data Monitoring Committee, but provision is included for an ad hoc Safety 
Review Committee, if needed. 

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1.2. 
Schema 
Figure 1: 
Study ALXN1840-HV-103 Schematic  
 
Participants will be admitted on Day -1 of each Period for Check in procedures. Eligible participants will be 
randomized on Day 1 immediately prior to dosing in Period 1. 
Participants will receive treatment (A or B) based on randomization on Day 1 of each period. 
Blood samples for PK analysis of total Mo (as a measure of ALXN1840) and bupropion will be collected in each 
period on Day 1 at pre-dose, 1, 2, 3, 4, 5, 6, 8, 12 and 24 hours (Day 2) and then at 24 hour intervals on Days 3, 4, 5, 
6, 7, 8, 9, 10, and Day 11. The nominal 336-hour sample for Period 1will be collected pre-dose in Period 2. 
Participants will be discharged on Day 11 of each period after completion of all procedures and review of all safety 
data. The end of study visit (EOS) will occur on Day 15 ± 2 of Period 2, with the collection of 336-hour PK sample 
for Period 2. 
Participants may be asked or required to stay in the CRU between Periods 1 and 2, and/or before the EOS visit, for 
their own safety, and also to maintain the integrity of the conduct of the study. 
 

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1.3. 
Schedule of Activities  
 Table 1: 
 
Schedule of Activities 
Study Procedures 
Sa C-Ib 
Treatment Periods 1 and 2 
EOS or ETc 
Days 
 
-28 
to -2 -1 
1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
11 
15 (±2) 
 
 
 
Pre-
dose 0d 1 2 
3 
4 
5 
6 
8 
12 24 48 72 96 120 144 168 192 216 240 
336e 
Eligibility 
Informed consent 
x 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Inclusion/exclusion criteria 
x 
x 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Pregnancy test 
x 
x 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
x 
Urine alcohol test 
x 
x 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Urine drug screen 
x 
x 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
HIV, Hepatitis B and C 
screen 
x 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Study Administrative 
Medical 
history/demographicsf 
x 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Physical examinationg 
x 
x 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
x 
Weight 
x 
x 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Height and BMI  
x 
 
 
 
 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
Discussion/documentation 
of contraception method 
x 
x 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Randomization 
 
 
 
xh 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Administration of Study Interventioni  
Treatment A: bupropion or 
Treatment B: bupropion + 
ALXN1840 
 
 
 
x 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
PK Blood Sample 
Bupropion 
(Hydroxybupropion) and 
ALXN1840 PK  
 
 
x 
 
x 
x 
x 
x 
x 
x 
x 
x 
x 
x 
x 
x 
x 
x 
x 
x 
x 
x 
x 
Pharmacogenetic sample 
CYP2B6 genotyping 
 
x 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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Table 1: 
 
Schedule of Activities (Continued)  
 
Study Procedures 
Sa C-Ib 
Treatment Periods 1 and 2 
EOS or ETc 
Days 
 
-28 
to -2 -1 
1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
11 
15 (±2) 
 
 
 
Pre-
dose 0d 1 2 
3 
4 
5 
6 
8 
12 24 48 72 96 120 144 168 192 216 240 
336e 
Laboratory Assessments 
Chemistryj, hematology, 
coagulation  
x 
x 
 
 
 
 
 
 
 
 
 
 
x 
 
 
x 
 
 
 
 
x 
 
x 
Follicle stimulating 
hormonek  
x 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Urinalysis  
x 
x 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Vitals signs measurements  
x 
 
x 
 
x 
 
 
x 
 
 
x 
x 
x 
 
 
 
 
 
 
 
 
 
x 
12-Lead ECGl 
x 
 
x 
 
 
 
 
x 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Retained sample (safety)m 
 
 
x  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
AE monitoring and 
concomitant therapies 
review 
 
a Within 28 days prior to Day 1 of the first dose of study drug in Dosing Period 1. Note that Screening only occurs once. 
b Participants will be admitted to the CRU at least 10 hours prior to study intervention. 
c Participants are required to return to the CRU approximately Day 15 (± 2 days) following the final dose of study medication for an EOS evaluation. 
Participants may be asked or required to stay in the CRU between Periods 1 and 2, and/or before the EOS visit, for their own safety, and also to maintain the 
integrity of the conduct of the study. In the event of early termination/discontinuation (ET), the procedures listed at the EOS are performed prior to participant 
discharge. 
d Hour 0 corresponds to the time of bupropion ± ALXN1840 administration. Unless stated otherwise, times listed are in relation to bupropion ± ALXN1840 
dosing. 
e The nominal 336-hour sample for Period 1 is to be collected pre-dose in Period 2. 
f Parameters include age and sex. Race and ethnicity will be collected where permitted by local regulations. 
g A full physical examination will be performed at Screening, Check-in for each period, and at the end of the study or upon ET. A symptom-driven physical 
 
h Randomization will occur before dosing. 
i Each dose administration will be separated by at least 14 days between bupropion alone or in combination with ALXN1840 doses. There will be a minimum of 
14 days between Day 1 of Period 1 and Day 1 of Period 2.  
j Samples for chemistry will be obtained following a fast of at least 6 hours at Screening, and at Check-in. In case of dropouts, rechecks, and post dose 
chemistry, fasting is not required (Section 10.2). 
k Only needed if claiming exemption from contraception requirement due to menopause. 

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l Triplicate 12-lead ECG will be taken at screening, pre-dose, and at 4 hours post-dose (before lunch) on Day 1. ECGs will be conducted before PK blood 
sampling if these 2 events are scheduled to occur at the same time. 
m A single 12 mL sample will be retained for evaluation in the event of an unexpected safety finding; retained samples may be destroyed after completion of the 
clinical study report. The retained serum sample will only be collected pre-dose on Day 1 of Period 1.  
 
Abbreviations: AE = adverse event; BMI = body mass index; C-I = Check-in; CRU = clinical research unit; ECG = electrocardiogram; EOS = End of Study; 
ET = Early Termination; FSH = follicle-stimulating hormone; HIV = human immunodeficiency virus; HR = heart rate; PI = Principal Investigator; 
PK = pharmacokinetics; S = Screening. 
 

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2. 
INTRODUCTION 
ALXN1840 (bis-choline tetrathiomolybdate; formerly known as WTX101) is a novel, 
first-in-class, copper (Cu)-protein binding agent in development for the treatment of Wilson 
disease (WD) and primary biliary cholangitis (PBC). 
2.1. 
Study Rationale 
This study is being conducted to determine the effect of ALXN1840 at a single dose of 60 mg on 
the metabolism of bupropion, a sensitive cytochrome P450 2B6 (CYP2B6) substrate, at a single 
dose of 150 mg (WELLBUTRIN SR). ALXN1840 is considered to have the potential for weak 
to moderate drug-drug interactions (DDI) due to inhibition of CYP2B6, according to in vitro 
studies conducted using human liver microsomes and simulations performed to assess DDI risks 
(Study CYP0840-R2, Study 1907124 and Study AXP/1/B). This study has been designed and 
will be conducted in accordance with the current regulatory guidance issued by the US Food and 
 Cytochrome P450 Enzyme- 
and Transporter-Me
n of Drug 
 
 
Based on a mean ALXN1840 maximum observed plasma concentration (Cmax) value of 3.92 
with a single dose of 60 mg enteric-coated (EC) tablet under fasting conditions in healthy 
participants (Study WTX101-102), a steady state plasma total Mo Cmax of 13.03 
estimated, considering accumulation ratio of 3.33 with linear PK. In the Phase 2 Study 
WTX101-201, conducted in patients with WD, the observed highest plasma total molybdenum 
(Mo) concentration was 20.3 µM after repeated dosing at 60 mg; the dose was escalated to 
120 mg at Week 4. Assuming all tetrathiomolybdate (the active ingredient in ALXN1840) in 
human plasma is free (a conservative approximation since 90% - 95% of the total Mo in plasma 
is bound to copper and albumin by forming tripartite complexes), there is no potential that 
ALXN1840 may induce cytochrome P450 (CYP) isoforms or inhibit p-glycoprotein, breast 
cancer resistance protein, or the organic anion and organic cation uptake transporters. However, 
as the estimated in vivo steady-state plasma levels of total Mo after dosing at 60 mg daily (13.03 
µM) may exceed the drug concentration required to produce 50% of the maximal inhibition 
(IC50 value = 9.9 µM) of CYP2B6 in vitro, a moderate potential for inhibition of CYP2B6 was 
theoretically and conservatively anticipated (Study 030519b, Study 030709c, Study MC05063, 
and Study CYP0840-R2). 
Subsequent in vitro studies in human liver microsomes (HLM) have shown a potential inhibitory 
effect (competitive and time-dependent) of ALXN1840 (and possibly its degradation products) 
on CYP2B6-mediated metabolism (Study CYP0840-R2 and Study 1907124). The IC50 value for 
the inhibitory effect on CYP2B6 was observed at 9.9 µM (4.3 µg/mL) with the estimated Ki 
values of 4.7 µM (2.0 µg/mL; Study CYP0840-R2, Study 1907124 and Study AXP/1/B). 
Furthermore, the Study 1907124 specifically examining the inactivation potential of ALXN1840 
on CYP2B6 catalytic activity in vitro using HLM and the FDA recommended CYP2B6 probe 
substrate bupropion with the time-dependent probe inhibitor ticlopidine as active control (US 
Food and Drug Administration), demonstrated potential for time-dependent inhibition (TDI) at 

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 µM. Because the maximum observed plasma total Mo 
concentration in the Phase 2 Study WTX101-201, conducted in patients with WD was 20.3 µM 
after repeated doing at 60 mg and then dose-escalated to 120 mg at Week 4, the observed in vitro 
 µM is not anticipated in vivo even 
considering total Mo of 20.3 µM is 100% active and free ALXN1840. Assuming 10% of the 
total Mo is in the form of free and active ALXN1840, which is still conservative given that most 
of this 10% are likely ALXN1840 degradants such as molybdate, then the highest anticipated 
individual free and active ALXN1840 concentration is at 2.03 
WD, when 
dosed at 120 mg daily at steady state. Overall, this, implies a negligible possibility for observing 
in vivo TDI with repeated daily doses of ALXN1840 at 60 mg or up to 120 mg in patients with 
WD. 
Finally, a validated Simcyp® physiologically based pharmacokinetic model, developed using 
data from Study WTX101-HV-106, predicted a weak CYP2B6 inhibition potential for 
simulations of single dose ALXN1840 exposures at120 or 240 mg. The predicted geometric 
mean of the AUC ratio of bupropion was 1.08 for the highest simulated single dose of 240 mg 
ALXN1840 (Study AXP/1/B), indicating weak inhibitory potential in vivo (weak for AUC ratio 
- to < 2-fold), per the 2020 FDA guidance on 
 
Cytochrome P450 Enzyme- and Transporter-
. For the highest 
simulated single dose of 240 mg ALXN1840, the maximum in vivo estimated free plasma 
concentration available to interact with CYP2B6 is estimated at 4.7 µM, after accounting for the 
formation of tetrathiomolybdate-Cu-albumin tripartite complexes (TPC), which is higher than 
the 2.03 µM noted above. 
Overall, based on in vitro and in silico study results, the maximum total daily doses in clinical 
studies (currently 60 mg in Phase 3 Study WTX101-301, but previously up to 120 mg in Phase 2 
Study WTX101-201) are not anticipated to reach steady-state ALXN1840 concentrations 
associated with TDI. 
Studies - Cytochrome P450 Enzyme - and Transporter-
 a 
single dose study design using the highest anticipated clinically relevant dose will be appropriate 
and justified if there is no TDI. Therefore, single dose of ALXN1840 at 60 mg, which is the 
highest allowed dose in the on-going Phase 3 Study WTX101-301 conducted for treating patients 
with WD, is justified to be tested as a potential perpetrator for the CYP2B6 metabolism of a 
sensitive substrate bupropion.  
CYP2B6 has been involved in the metabolism of 2%  10% of clinically used drugs (Hedrich, 
2016). Common substrates of CYP2B6 include, but are not limited to, artemisinin, bupropion, 
cyclophosphamide, efavirenz, ketamine, methadone, propofol, rifampicin, and sertraline. The 
potentially weak to moderate inhibitory effects of a single 60 mg ALXN1840 dose on a single 
dose 150 mg bupropion metabolism is anticipated to have a very limited safety concern (such as 
seizures), since a 2-fold increase in bupropion concentration is not anticipated (WELLBUTRIN 
SR). 
Further details of the currently available drug metabolism, pharmacokinetics, and safety data are 
 

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2.2. 
Background 
ALXN1840 has been in development for the treatment of WD and PBC due to its improved 
stability properties over ammonium tetrathiomolybdate, the latter of which has previously been 
studied in patients with WD and other indications. Ammonium tetrathiomolybdate as well as 
bis-choline tetrathiomolybdate non-clinical and clinical data reported to date support therapeutic 
efficacy with an appropriate safety profile for ALXN1840. 
ALXN1840 rapidly forms irreversible TPC, which stabilize free and potentially toxic Cu leading 
to a reduction in the non-ceruloplasmin-bound Cu (NCC) concentrations or NCC corrected for 
TPC [NCCcorrected]) (Weiss, 2017). 
Detailed descriptions of the chemistry, pharmacology, efficacy, and safety of ALXN1840 are 
provided in the IB for ALXN1840. 
2.3. 
Benefit/Risk Assessment 
More detailed information about the known and expected benefits and risks and reasonably 
expected adverse events (AEs) forALXN1840 may be found in the IB and of bupropion in the 
prescribing information (WELLBUTRIN SR). 
2.3.1. 
Risk Assessment 
Details of the potential risks and mitigation strategy are provided in Table 2.  
Table 2:  
Potential Risks and Mitigation Strategy 
Potential Risk of Clinical 
Significance 
Summary of Data/Rationale 
for Risk 
Mitigation Strategy 
ALXN1840 
Dose-dependent elevations in 
transaminases (ALT and AST) 
Generally mild to moderate in 
severity, asymptomatic and 
reversible with dose adjustments 
were reported, usually after 
3 - 6 weeks of treatment in patients 
with WD 
Regular monitoring of liver 
function tests  
Anemia 
Anemia has been observed in 
patients with WD, PBC and cancer, 
attributed to overtreatment and 
resultant Cu depletion
Monitoring complete blood count  
Low white blood cell count 
(leukopenia, bone marrow toxicity)  
Leukopenia and bone marrow 
toxicity (myelosuppression) have 
been observed in patients with WD 
and attributed to overtreatment and 
resultant Cu depletion 
Monitoring complete blood count 
Study Procedures 
Risks associated with the study 
design and procedures  
Participants will undergo repeated 
blood draws to measure the PK of 
the study intervention and 
metabolism. Blood draws may 
result in ecchymosis, redness and 
Blood draws are optimized for PK.  
A cannula may be placed to 
minimize needle sticks 

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Abbreviations: ALT = alanine aminotransferase; AST = aspartate aminotransferase; Cu = copper; 
IB = 
re; PBC = primary biliary cholangitis; PK = pharmacokinetics; WD = Wilson Disease. 
2.3.2. 
Benefit Assessment 
This is a healthy volunteer study, and there is no direct benefit to study participants.  
2.3.3. 
Overall Benefit: Risk Conclusion 
Taking into account the measures implemented to minimize risk to participants, the potential 
risks identified in association with ALXN1840 and bupropion are justified by the anticipated 
benefits that may be afforded to patients with WD and PBC. 
minor pain to the site. On rare 
occasion, infection or 
thrombophlebitis can occur  
Bupropion 
As per prescribing information 
Bupropion prescribing information 
(WELLBUTRIN SR) 
Participants will be monitored for 
adverse reactions and by regular 
laboratory assessments. Participants 
may be discontinued for significant 
drug related adverse events  

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3. 
OBJECTIVES AND ENDPOINTS 
Objectives 
Endpoints 
Primary 
 
 
To determine the effect of ALXN1840 on the 
PK of bupropion, a sensitive CYP2B6 
substrate 
 
PK parameters of bupropion (Cmax, area under 
the plasma concentration (AUC) versus time 
curve from time 0 to the last quantifiable 
concentration [AUCt], and AUC versus time 
curve from time 0 to infinity [AUC ]) with 
and without the coadministration of 
ALXN1840 
Secondary 
 
 
To determine the effect of ALXN1840 on the 
PK of hydroxybupropion, the major active 
metabolite of bupropion   
 
To determine the effect of ALXN1840 on the 
PK of plasma Mo with the coadministration of 
bupropion 
 
To determine the safety and tolerability of 
ALXN1840, with the coadministration of 
bupropion  
 
PK parameters of hydroxybupropion (Cmax, 
AUCt, and AUC ) with and without the 
coadministration of ALXN1840 
 
PK parameters for plasma total Mo (Cmax, 
AUCt, and AUC ) with the coadministration 
of bupropion 
 
Safety assessed by incidence of treatment-
emergent adverse events (TEAEs) and 
treatment-emergent serious adverse events 
(TESAEs), physical examination, vital signs 
measurements, clinical laboratory and 12-lead 
electrocardiogram (ECG) results 
Abbreviations: AUC  = area under the plasma concentration versus time curve from time 0 to infinity; AUCt = area 
under the plasma concentration versus time curve from time 0 to the last quantifiable concentration; 
Cmax = maximum observed plasma concentration of the drug; CYP2B6 = cytochrome P450 2B6; 
ECG = electrocardiogram; PK = pharmacokinetics; TEAE = treatment-emergent adverse event; TESAE = treatment-
emergent serious adverse event. 

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4. 
STUDY DESIGN 
4.1. 
Overall Design 
The study is being conducted as a randomized, 2-period, 2-sequence, cross-over study to 
determine the effect of a single dose of ALXN1840 (perpetrator) on the single dose bupropion 
(victim) kinetics in healthy male and female participants.  
The study has a Screening period (Day -28 to Day -2), two 11-day study periods (Day 1 to 
Day 11) with a minimum of 14 days between doses of bupropion, and an End of Study (EOS) 
Visit (Day 15 ± 2 days) after Period 2 dosing. Participants will report to the clinical research unit 
(CRU) on the day prior (Day -1) to both dosing periods. 
All participants will receive 1 treatment in each study period; treatment order will be defined 
based on randomization:  
 Treatment A: One 150 mg bupropion HCl salt tablet (WELLBUTRIN SR 150) with 
240 mL water (fasting). 
 Treatment B: One 150 mg bupropion HCl salt tablet (WELLBUTRIN SR 150) + 
4 × 15 mg ALXN1840 EC tablets with 240 mL water (fasting). 
Based on randomization, participants will be administered either Treatment A or Treatment B in 
each period. A wash-out period of at least 14 days must separate dose administration in Period 1 
and Period 2. Participants will remain institutionalized from the day prior to dosing until Day 11 
following dose administration for each period. 
The PK profile of ALXN1840 and bupropion will be determined by blood sampling following 
single dose administration over approximately 5 half-lives or more for both study interventions. 
Blood sampling for PK assessments will occur at pre-dose, 1, 2, 3, 4, 5, 6, 8, 12, 24, 48, 72, 96, 
120, 144, 168, 192, 216, 240, and 336 hours post-dose to ensure full assessment of exposure over 
time. The nominal 336-hour sample for Period 1 is pre-dose sample for Period 2. In addition to 
PK sampling, safety and tolerability will be assessed by monitoring AEs, vital signs, 12-lead 
electrocardiograms (ECGs), and laboratory parameters. 
Following scheduled procedures on Day 11, participants will be discharged from the unit. If 
there are any participants with clinically significant abnormalities at the time of discharge, the 
Investigator should notify the Medical Monitor prior to discharge, and participants may be asked 
to remain institutionalized for further clinical monitoring.  
Participants may be asked or required to stay in the CRU between Periods 1 and 2, and/or before 
the EOS visit, for their own safety, and also to maintain the integrity of the conduct of the study. 
The End of Study (EOS) Visit will occur approximately 4 days after discharge from Period 2 
after collection of the nominal 336-hour PK sample.  
This study will include approximately 52 participants to complete at least 32 participants. 
Participants will be randomized to one of two sequences as described in Table 3.  
 

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Table 3: 
Study Design  
Sequence number 
Treatment sequence 
Total 
Study Period 1 
Study Period 2 
1 
A 
B 
26 
2 
B 
A 
26 
Total 
52 
Treatment A - One 150 mg bupropion HCl salt tablet (WELLBUTRIN SR 150) with 240 mL water (fasting) 
Treatment B  One 150 mg bupropion HCl salt tablet (WELLBUTRIN SR 150) + 4 × 15 mg ALXN1840 
enteric-coated tablets with 240 mL water (fasting) 
 additional participants may be screened to allow for a full 
enrollment of the study; therefore, it is possible that all eligible participants may not be included. 
Participants not included in the study will be discharged without dosing on Day 1. 
4.2. 
Scientific Rationale for Study Design 
This study is being conducted in healthy participants so that the assessments are not confounded 
by disease activity, comorbidities, or concomitant medications. The inclusion and exclusion 
criteria for this study are consistent with Phase 1 clinical pharmacology studies that assess the 
medication of interest and to minimize assignment bias. 
A 2-way crossover study design was adopted to control the variability within and between 
participants. Given the desire to evaluate the impact of sequence of administration, the study is 
being conducted as a 2-sequence, 2-period cross-over study. Blood sampling for PK assessment 
will include measures for ALXN1840 and bupropion. Blood sampling timepoints support 
evaluation of time to reach maximum observed plasma concentration (Tmax) and Cmax and include 
a minimum of 5 half-lives between each study intervention. 
The interval between dose administration in each period will be at least 14 days, based on the 
estimated mean half-life for ALXN1840 of approximately 2 days as previously reported in the 
bioavailability studies (Studies WTX101-101 and WTX101-102), where healthy participants 
took an oral dose at 60 mg. Therefore, a minimum of 14 days between dose administration is 
considered sufficient to eliminate, on average, approximately more than 99.2% of the plasma 
total Mo before a second dose of bupropion. The approximately 4-day interval after Period 2 
dose administration will also ensure that the participants will have eliminated measurable 
concentrations of ALXN1840 at the EOS Visit regardless of the randomized dosing sequence. 
The mean elimination half-life (±SD) of bupropion after chronic dosing is 21 (± 9) hours, 
therefore a minimum of 14-day interval between single dose administrations is sufficient to 
eliminate greater than 99.2% of plasma bupropion.  
4.3. 
Justification for Dose 
ALXN1840 
The maximum tolerated dose (MTD) of ALXN1840 is unknown. To date, the 60 mg single dose 
and repeated daily doses have shown a good safety profile and were well tolerated throughout 
the Phase 1 to Phase 3 clinical studies. The 60 mg dose is well within the dose range 
demonstrated to have a good safety profile in studies in healthy volunteers and patients with WD. 
The 60 mg dose is well within the dose range to have an acceptable safety profile in humans as 

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demonstrated in the completed bioavailability studies that were conducted in healthy male and 
female participants (Study WTX101-101 and Study WTX101-102) with a median (range) body 
weight of 80.8 kg (57.6 to 107.0 kg) as well as the completed Study WTX101-201, conducted in 
patients with WD.  
Tetrathiomolybdate reacts with albumin-bound Cu in the liver or blood to form a stable tripartite 
complex which is excreted into the bile. Tetrathiomolybdate which does not bind to Cu and 
albumin, is not metabolized by the liver but undergoes hydrolysis to form molybdate anion, 
which is excreted in the urine. Therefore, findings from the human microsome study 
(Study CYP0840-R2) are considered an over-estimation of the effect to be observed in vivo. 
Given that in vitro inhibition was observed with the ALXN1840 parent drug and no apparent 
accumulation of free ALXN1840 as part of the plasma ultrafiltrate (PUF) Mo or non-TPC-bound 
Mo after ALXN1840 repeated dosing (preliminary results from Study WTX101-201), a single 
dose of ALXN1840 is considered to be sufficient to assess the inhibition potential of CYP2B6 
using bupropion as the substrate. Single dose administration of the ALXN1840 tablet under 
fasted conditions resulted in a peak drug concentration of total Mo at approximately 4.54 hours, 
with a half-life of approximately 51 hours (Study WTX101-102).  
Bupropion 
Bupropion is extensively metabolized in humans. Following oral administration of 150 mg of 
14C-bupropion in humans, 87% and 10% of the radioactive dose were recovered in the urine and 
feces, respectively. The fraction of the oral dose of bupropion excreted unchanged was only 
0.5%, a finding consistent with the extensive metabolism of bupropion (WELLBUTRIN SR).  
In humans, following oral administration of WELLBUTRIN SR tablet, peak plasma bupropion 
concentrations are usually achieved within 3 hours, followed by a biphasic decline. The terminal 
phase has a mean half-life of 14 hours, with a range of 8 to 24 hours. The mean elimination half-
life (± SD) of bupropion after chronic dosing is 21 (± 9) hours, and steady-state plasma 
concentrations of bupropion are reached within 8 days. Plasma bupropion concentrations are 
dose-proportional following single doses of 100 to 250 mg. 
Three metabolites have been shown to be active: hydroxybupropion, formed via hydroxylation of 
the tert-butyl group of bupropion, and the amino-alcohol isomers threohydrobupropion and 
erythrohydrobupropion, which are formed via reduction of the carbonyl group. In vitro findings 
suggest that cytochrome P450IIB6 (CYP2B6) is the principal isoenzyme involved in the 
formation of hydroxybupropion, while cytochrome P450 isoenzymes are not involved in the 
formation of threohydrobupropion. Oxidation of the bupropion side chain results in the 
formation of a glycine conjugate of meta-chlorobenzoic acid, which is then excreted as the major 
urinary metabolite. Because bupropion is extensively metabolized, there is the potential for 
drug-drug interactions, particularly with those agents that are metabolized by the cytochrome 
P450IIB6 (CYP2B6) isoenzyme. Following a single dose in humans, peak plasma concentrations 
of hydroxybupropion occur approximately 6 hours after administration of WELLBUTRIN SR 
tablets. Peak plasma concentrations of hydroxybupropion are approximately 10 times the peak 
level of the parent drug at steady state. The elimination half-life of hydroxybupropion is 
approximately 20 (± 5) hours, and its AUC at steady state is about 17 times that of bupropion. 
The times to peak concentrations for the erythrohydrobupropion and threohydrobupropion 
metabolites are similar to that of the hydroxybupropion metabolite. However, their elimination 

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half-lives are longer, 33 (± 10) hours and 37 (± 13) hours, respectively, and steady-state AUCs 
are 1.5 and 7 times that of bupropion, respectively.  
Even though ALXN1840 is considered theoretically and conservatively to have potential for 
moderate inhibition of CYP2B6 in vitro. A dose of 150 mg is not expected to result in 
sufficiently high exposure to cause an increase in safety risk. 
4.4. 
End of Study Definition 
A participant is considered to have completed the study if he/she has completed all phases of the 
study including the last scheduled procedure shown in the Schedule of Activities (SoA). 
The end of the study is defined as the date the last participant completes the last visit as shown in 
the SoA (Table 1). 

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5. 
STUDY POPULATION 
Prospective approval of protocol deviations to recruitment and enrollment criteria, also known as 
protocol waivers or exemptions, is not permitted. 
5.1. 
Inclusion Criteria 
Participants are eligible to be included in the study only if all of the following criteria apply: 
Age 
1. Participants must be 18 to 50 years of age inclusive, at the time of signing the informed 
consent. 
Type of Participant and Disease Characteristics 
2. Participants who are healthy as determined by medical evaluation including medical 
history, physical examination, vital signs, 12-lead ECG, and clinical laboratory 
evaluation (hematology, biochemistry, coagulation, and urinalysis) that are reasonably 
likely to i
or to potentially confound interpretation of study results, as assessed by the Investigator.  
3. Adequate venous access in the left or right arm to allow collection of a number of blood 
samples.  
Weight 
4. 
 
 100 kg and body mass index (BMI) within the range of 18 to 
< 30 kg/m2 at Screening.  
Sex 
5. Contraceptive use by men or women should be consistent with local regulations 
regarding the methods of contraception for those participating in clinical studies. 
a. Male Participants: 
 Male participants, if heterosexually active with a female spouse or partner of 
childbearing potential or a pregnant or breastfeeding spouse or partner, must agree to 
use barrier contraception (male condom) for the duration of the study and for at least 
3 months after the end of systemic exposure of the study intervention (ie, 3 months 
after the EOS Visit). Male participants must also agree to not donate sperm for at 
least 3 months after the end of systemic exposure of the study intervention (ie, 
3 months after the EOS Visit). 
 Female spouses or partners of male participants who are of childbearing potential 
must use highly effective contraception as defined below and in Section 10.4, starting 
administration and continuing until at least 3 months after the end of their male 
tervention (ie, 3 months after the EOS 
Visit).  
 Barrier contraception is required even with documented medical assessment of 
surgical success of a vasectomy. For male participants who have had a vasectomy 

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(with documented evidence of azoospermia if possible) and agree to use a barrier 
method (male condom) for the stated time period, no additional contraceptive method 
is required by their female partner. 
b. Female Participants: 
 Female participants or female partners of male participants of childbearing potential 
(including breastfeeding females), if heterosexually active, must be willing to follow 
protocol-specified contraception guidance starting at least 1 menstrual cycle before 
first study intervention administration and continuing for at least 3 months after the 
end of systemic exposure of the study intervention (ie, 3 months after the EOS Visit). 
Female participants must not donate ova for at least 3 months after the EOS (ie. 
3 months after the EOS Visit). 
 Female participants who are documented as being of non-childbearing potential as 
defined in Section 10.4 are exempt from contraception requirements.  
 Highly effective contraceptive methods for female participants and female partners of 
male participants are described in Section 10.4.  
 Women of childbearing potential must have a negative highly sensitive serum 
pregnancy test at screening. Additional urine pregnancy testing will be standard for 
the protocol unless serum testing is required by site policies, local regulation, or 
IRB/IEC and should be performed per the time points specified in the SoA (Table 1:  
Informed Consent 
6. Capable of giving signed informed consent as described in Section 10.1.3, which includes 
compliance with the requirements and restrictions listed in the informed consent form 
(ICF) and in this protocol. 
5.2. 
Exclusion Criteria  
Participants are excluded from the study if any of the following criteria apply: 
Medical Conditions  
1. History or presence of/significant history of or current cardiovascular, respiratory, 
hepatic, renal, gastrointestinal, endocrinological, hematological, neurological disorder, 
seizure disorder or eating disorder (anorexia or bulimia). Participants with a history of 
gastric bypass, other surgical procedure, or medical condition that may significantly alter 
absorption of drugs.  
2. Clinically significant multiple or severe drug allergies, food allergies, or allergies to study 
product or class of product or its derivatives.  
3. Lymphoma, leukemia, or any malignancy within 5 years of Screening, except for basal 
cell or squamous epithelial carcinomas of the skin that have been resected with no 
evidence of metastatic disease for 3 years. 
4. Breast cancer within the past 10 years. 
5. Serum creatinine > upper limit of normal (ULN) of the reference range of the testing 
laboratory at Screening or on Check-in Period 1.  

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6. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), or total bilirubin > 
ULN of the testing laboratory at Screening and Check-in. Participants with confirmed 
 ULN but below 3 × ULN if 
participant has a measured direct bilirubin < ULN.  
7. Current or chronic history of liver disease or known hepatic or biliary abnormalities (with 
the exception of Gilbert's syndrome or asymptomatic gallstones). 
8. QTc > 450 msec for male participants or > 470 msec for female participants 
NOTE A: The QTc is the interval between the start of the Q-wave and the end of the 
T-
), and/or another method. It is machine-read with 
Investigator review. 
NOTE B: The specific formula used to determine eligibility and discontinuation for an 
individual participant should be determined prior to initiation of the study; QTcF is 
preferred; however, QTcB may be used if QTcF cannot be measured. 
Prior/Concomitant Therapy 
9. Use or intended use of prescription medications (excluding oral contraceptives) within 
14 days or 5 half-lives of the drug (whichever is longer) prior to dosing on Day 1, except 
with prior approval of Alexion. Participants may not have a medical condition that 
requires chronic medicinal therapy. 
10. Use of nonprescription/ over-the-counter medications, including herbal remedies and 
supplements, within 7 days prior to dosing on Day 1 and/or intended use at any point 
over the duration of the study.  
Prior/Concurrent Clinical Study Experience 
11. Participation in a study resulting in loss of blood or donation of blood products in excess 
of 500 mL within 60 days prior to Day 1. 
12. Exposure to more than 4 new investigational drugs within 12 months prior to dosing.  
13. Current enrollment or past participation within the last 90 days before signing of consent 
in this or any other clinical study involving an investigational study intervention or any 
other type of medical research. For participants recently participating in clinical studies 
involving an investigational product with a prolonged half-life, participants may not 
participate in this study within 5-half-lives of the last dose administration. 
Diagnostic assessments 
14. Presence of hepatitis B surface antigen (HBsAg) at Screening or within 3 months prior to 
first dose of study intervention. Presence of HBsAg or positive hepatitis C antibody or 
ribonucleic acid (RNA) test result at screening or within 3 months prior to first dose of 
study intervention.  
 NOTE: Participants with positive hepatitis C antibody due to prior resolved disease 
can be enrolled if a confirmatory negative hepatitis C RNA test is obtained.  
 NOTE: The RNA test is optional and participants with negative hepatitis C antibody 
test are not required to also undergo hepatitis C RNA testing. 

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15. Positive pre-study alcohol or drugs of abuse screen. 
16. Positive human immunodeficiency virus (HIV) antibody test.  
17. Ongoing use of tobacco products or nicotine delivery systems. 
Other Exclusions 
18. Regular alcohol consumption within 6 months prior to the study defined as: an average 
weekly intake of > 14 units/week for males or > 7 units/week for females. One unit is 
equivalent to 8 g of alcohol: a half pint (~240 mL) of beer, one ~4 oz glass (125 mL) of 
wine or 1 (25 mL) measure of spirits. 
19. Regular use of known drugs of abuse, based on the assessment of the investigator. 
20. Prior exposure to ALXN1840 or other tetrathiomolybdate salt. 
21. Sensitivity to any of the study interventions, or components thereof, or drug or other 
allergy that, in the opinion of the Investigator or Medical Monitor, contraindicates 
participation in the study.  
5.3. 
Lifestyle Considerations 
Participants must be able and willing to adhere to the following lifestyle restrictions. 
Table 4: 
Healthy Participant Lifestyle Considerations  
Items Participants Must Not 
Consume or Do 
When Participants Must Stop 
When Participants Can 
Restart 
Tobacco in any form (eg, smoking 
or chewing) or other nicotine-
containing products in any form 
(eg, gum, patch, electronic 
cigarettes or vaporized inhalation 
device)
From Screening 
After the final study visit 
Alcohol 
48 hours before Check-in to the 
CRU (Day -1) and until discharge 
(Day 11), and 48 hours before the 
EOS Visit
Discharge from the clinical research 
unit and completion of EOS visit 
Meals/snacks/water 
 
Breakfast will be omitted on the 
Day of dosing (Day 1). With the 
exception of the day of dosing, 
water/fluids may be consumed ad 
libitum. On the day of dosing, 
participant must refrain from water 
intake from 1 hour before to one 
hour after with the exception of the 
240 mL water provided for dose 
administration. On Day-1, Check-in 
for Period 1 and 2, the evening 
meal must be completed no later 
than 2100 hours. Participants will 
continue fasting for approximately 
4 hours after dosing
Standard meals will be provided 
during institutionalization  

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Table 4: 
Healthy Participant Lifestyle Considerations  (Continued) 
Items Participants Must Not 
Consume or Do 
When Participants Must Stop 
When Participants Can 
Restart 
Not consume any other substances 
known to be potent inhibitors or 
inducers of CYP450 enzymes. This 
includes food or drink products 
containing cranberry, pomegranate, 
star fruit, grapefruit, pomelos, 
exotic citrus fruits or Seville 
oranges (including marmalade and 
juices made from these fruits). Red 
wine should also not be consumed 
Within 7 days before the planned 
first study intervention 
administration 
After collection of the final PK 
sample for each study period 
Caffeine-containing or xanthine-
containing products (eg, tea, coffee, 
cola drinks, and chocolate). 
During each dosing period, 
24 hours before the planned first 
study intervention administration 
and each outpatient/ follow-up visit 
After collection of the final PK 
sample for each study period  
Strenuous physical activity  
Starting 72 hours prior to each 
blood collection for clinical 
laboratory tests. Participants may 
participate in light recreational 
activities during studies (eg, 
watching television, reading). 
After study completion/last visit. 
Participants should not start new 
physical training activities during 
the study until study completion 
(last visit). 
Any prescription medication. For 
details, see Section 5.2  
Note: If participants have a medical 
need to take any medication or have 
any medications prescribed to them 
by a doctor, they should follow the 
medical advice but inform the 
Investigator as soon as possible 
afterwards. Participants should be 
informed not to stop taking any 
medication that has been prescribed 
by their doctor
14 days or 5 half-lives prior to 
dosing on Day 1 
After the final study visit 
Any nonprescription/over-the-
counter medication, including 
herbal remedies and supplements. 
For details, see Section 5.2 
Use of nonprescription/ over-the-
counter medications, within 7 days 
prior to dosing on Day 1 and/or 
intended use at any point over the 
duration of the study. 
 
With Investigator approval, 
participants may take up to 
1000 mg/day of acetaminophen 
After the final study visit 
Any herbal remedy or dietary 
Wort
2 weeks before the planned first 
study intervention administration 
After study completion/last visit 
Blood and plasma donation 
Participation in a study resulting in 
loss of blood or donation of blood 
products in excess of 500 mL 
within 60 days prior to Day 1 
(Section 5.2)
1 month after study completion/last 
visit 

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Items Participants Must Not 
Consume or Do 
When Participants Must Stop 
When Participants Can 
Restart 
Participants must comply with the 
appropriate contraceptive 
requirements as stated in 
Section 10.4 
Start times for contraceptives vary 
according to method used (see 
applicable contraceptive method in 
Section 10.4.) 
See Section 10.4 
 
Abbreviations: CYP450 = cytochrome P450; PK = pharmacokinetics. 
5.4. 
Screen Failures 
Screen failures are defined as participants who consent to participate in the clinical study but are 
not subsequently randomly assigned to study intervention. A minimal set of screen failure 
information is required to ensure transparent reporting of screen failure participants to meet the 
Consolidated Standards of Reporting Trials (CONSORT) publishing requirements and to 
respond to queries from regulatory authorities. Minimal information includes demography, 
screen failure details (eg, failed eligibility criteria), and any AEs, including any serious adverse 
events (SAEs) and any related concomitant medication, occurring during the screening period. 
Individuals who do not meet the criteria for participation in this study (screen failure) due to a 
reason that is expected to resolve or has resolved, may be rescreened based on discussion and 
agreement between the Investigator and the Medical Monitor. 

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6. 
STUDY INTERVENTION 
Study intervention is defined as any investigational intervention(s), marketed product(s), 
placebo, or medical device(s) intended to be administered to a study participant according to the 
study protocol. 
6.1. 
Study Intervention Administered 
Details of the study interventions administered in the study are provided in Table 5. 
ALXN1840 and bupropion will be administered at the morning of Day 1. 
Table 5: 
Details of Study Interventions Administered 
ARM Name 
Study Intervention 
Comparator 
Intervention 
Name 
ALXN1840 (formerly WTX101) 
Bupropion (Wellbutrin SR) 
Type  
Drug 
Drug 
Dose 
Formulation 
Tablet  
Tablet 
Unit Dose 
Strength(s) 
15 mg ALXN1840  
150 mg 
Dosage Level(s) 
Single dose 60 mg administered as 
4 × 15 mg ALXN1840 tablets 
Administered as a single dose (1 × 150 mg 
tablet) 
Route of 
Administration 
Oral 
Oral  
Use 
experimental/study intervention 
comparator/reference  
IMP and NIMP 
IMP  
IMP 
Sourcing 
Provided centrally by Alexion 
Provided by the site 
Packaging and 
Labeling 
ALXN1840 will be provided in treatment 
kits that will each have a unique 
identification number and be packaged and 
labelled in accordance with all applicable 
regulatory requirements. At a minimum, the 
treatment kit label will provide the 
following information: study Sponsor 
identification, batch number, directions for 
use, required storage conditions, caution 
-Limited 
by Federal Law to 
language), study identification, and expiry 
date
Bupropion will be provided as per the 
prescribing information 
Current/Former 
Name(s) or 
Alias(es) 
 - Bis-choline 
tetrathiomolybdate  
USAN - Tiomolibdate choline 
Wellbutrin SR 
Abbreviations: IMP = investigational medicinal product; NIMP = noninvestigational medicinal product; 
USAN = United States adopted name 
6.2. 
Preparation/Handling/Storage/Accountability 
1. Only participants enrolled in the study may receive study intervention and only 
authorized site staff may supply or administer the study intervention. All study 
intervention must be stored in a secure, environmentally controlled, and monitored 

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(manual or automated) area in accordance with the labeled storage conditions with access 
limited to the Investigator and authorized site staff. 
2. The Investigator and/or delegated staff (ie, Pharmacist) is responsible for study 
intervention accountability, reconciliation, and record maintenance (ie, receipt, 
reconciliation, and final disposition records). 
a. This responsibility includes the reporting of any product complaints to 
productcomplaints@alexion.com within 1 business day. A product complaint is 
defined as any written, electronic, or oral communication that alleges deficiencies 
related to the identity, quality, durability, reliability, usability, safety, effectiveness, or 
performance of a product or clinical study material and/or its packaging components 
after it is has been released for distribution to an end customer that affects the 
performance of such product. 
3. The Investigator or designee must confirm appropriate temperature conditions have been 
maintained during transit for all study intervention received and any discrepancies are 
reported and resolved before use of the study intervention. 
a. The ALXN1840 treatment kits should be stored at refrigerated conditions, 2°C to 8°C 
(36°F to 46°F). 
b. Bupropion should be stored according to the details in the package labeling. 
4. Further guidance and information for the final disposition of unused study interventions 
are provided in the Pharmacy Manual. 
6.3. 
Measures to Minimize Bias: Randomization and Blinding 
 This is an open-label, 2-period cross-over study where each participant will be 
randomized to 1 of 2 treatment sequences (AB or BA) to minimize selection bias in 
treatment assignment. 
 Eligible participants who meet all inclusion and no exclusion criteria included in the 
study will be assigned unique study participant numbers for enrollment. Study 
participant numbers will not be reallocated once assigned.  
6.4. 
Study Intervention Compliance 
When participants are dosed at the site, participants will receive study intervention directly from 
the Investigator or designee, under medical supervision. The date and time of the dose will be 
recorded in the source documents and/or in the case report form (CRF). If the primary 
documentation is other than the electronic case report form (eCRF), all primary documentation 
should be filed on site as source documents. The dose of study intervention and study participant 
identification will be confirmed at the time of dosing by a member of the study site staff other 
than the person administering the study intervention. Study site personnel will examine each 
outh to ensure that the study intervention was ingested. 
For additional information on study intervention compliance and management, refer to the 
Pharmacy Manual. 

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6.5. 
Concomitant Therapy 
Any medication or vaccine (including over-the-counter or prescription medicines, vitamins, 
and/or herbal supplements) or other specific categories of interest) that the participant is 
receiving from 14 days prior to the first dose of study intervention until EOS visit must be 
recorded along with: 
 Reason for use. 
 Dates of administration including start and end dates. 
 Dosage information including dose and frequency. 
The Medical Monitor should be contacted if there are any questions regarding concomitant or 
prior therapy. 
6.5.1. 
Allowed Medicine and Therapy 
 Paracetamol/acetaminophen at doses of a maximum 1,000 mg per day is permitted for 
use as an exception with the approval of the Investigator.  
 As per the ALXN1840 IB, in this study, Investigators should use caution in the 
co-administration of drugs known to be substrates of CYP2B6. Common substrates of 
CYP2B6 include ibuprofen, which is permitted in this study. Therefore, the 
Investigator must use ibuprofen with caution during the conduct of the study. With 
the exception of the day of dosing in each period, ibuprofen may be used with the 
eed 1,150 mg in any 24-hour 
period. 
 Topical skin products without significant systemic absorption are permitted for use 
 
 Concomitant medications are not allowed unless medically indicated and with 
agreement between Alexion and the Investigator. 
 Concomitant procedures are not allowed unless medically indicated and/or permitted 
by Alexion or the Investigator. 
6.5.2. 
Disallowed Medicine and Therapy 
Participants must refrain from use or intended use of any prescription medications (excluding 
oral contraceptives) within 14 days or 5 half-lives of the drug (whichever is longer) prior to 
dosing on Day 1 and for the duration of the study (ie, until completion of the EOS visit).  
Participants may not have a medical condition that requires chronic medicinal therapy. Use of 
nonprescription/over-the-counter medications, including herbal remedies and supplements, is not 
permitted within 7 days prior to dosing on Day 1 and for the duration of the study (ie, until 
completion of the EOS Visit). 
6.6. 
Dose Modification 
Not applicable. ALXN1840 and bupropion will be administered as single doses in the prescribed 
parts of the study. 

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6.7. 
Intervention After the End of the Study 
This is a healthy volunteer study and no follow-up intervention is planned. 

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7. 
DISCONTINUATION OF STUDY INTERVENTION AND 
PARTICIPANT DISCONTINUATION/WITHDRAWAL 
7.1. 
Discontinuation of Study Intervention 
In rare instances, it may be necessary for a participant to permanently discontinue (definitive 
discontinuation) the study intervention. If the study intervention is definitively discontinued, the 
participant should remain in the study to be evaluated for safety follow-up. See the SoA 
(Table 1) for data to be collected at the time of discontinuation of study intervention and follow-
up. 
Discontinuation of study intervention for abnormal liver function should be considered by the 
investigator if transaminase elevations (ie, AST or ALT) exceeds 3 × ULN or if the Investigator 
believes that it is in best interest of the participant. 
If a clinically significant finding is identified (including, but not limited to QTcF  500 ms or 
QTcB  500 ms), the Investigator or qualified designee will determine if the participant can 
continue in the study and if any change in participant management is needed. Review of the ECG 
printed at the time of collection must be documented. Any new clinically relevant finding should 
be reported as an AE. 
Participant should be considered for discontinuation from intervention if any of the following 
occur during the study: 
 Serious hypersensitivity reaction; 
 Severe uncontrolled infection; 
 Use of disallowed medication; 
 Pregnancy or planned pregnancy (see Section 10.4); or 
 Alexion or the Investigator deems it is necessary for the participant. 
See the SoA (Table 1) for samples and data to be collected at the time of study intervention 
discontinuation and follow-up and for any further evaluations that need to be completed. 
7.2. 
Participant Discontinuation/Withdrawal From the Study 
 All efforts should be made to ensure participants are willing to comply with study 
participation prior to conducting the screening procedures. The study staff should 
notify Alexion and their site monitor of all study withdrawals as soon as possible. The 
reason for participant discontinuation must be recorded in the source documents and 
CRF. 
 A participant may withdraw from the study at any time at his/her own request or may 
be withdrawn at any time at the discretion of the Investigator for safety, behavioral, 
compliance, or administrative reasons. This is expected to be uncommon. 
 At the time of discontinuing from the study, if possible, an Early Termination (ET) 
Visit should be conducted, as shown in the SoA (Table 1). See the SoA for data to be 
collected at the time of study discontinuation and follow-up and for any further 
evaluations that need to be completed. 

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 The participant will be permanently discontinued both from the study intervention 
and from the study at that time. 
 If the participant withdraws consent for disclosure of future information, Alexion may 
retain and continue to use any data collected before such a withdrawal of consent. 
 If a participant withdraws from the study, he/she may request destruction of any 
samples taken and not tested, and the Investigator must document this in the site 
study records. 
7.3. 
Lost to Follow-up 
A participant will be considered lost to follow-up if he or she repeatedly fails to return for 
scheduled visits and is unable to be contacted by the study site. 
The following actions must be taken if a participant fails to return to the clinic for a required 
study visit: 
 The site must attempt to contact the participant and reschedule the missed visit as 
soon as possible and counsel the participant on the importance of maintaining the 
assigned visit schedule and ascertain whether or not the participant wishes to and/or 
should continue in the study. 
 Before a participant is deemed lost to follow-up, the Investigator or designee must 
make every effort to regain contact with the participant (where possible, 3 telephone 
calls and, if necessary, a certified letter to the p
address or local equivalent methods). These contact attempts should be documented 
 
 Should the participant continue to be unreachable, he/she will be considered to have 
withdrawn from the study.  
Discontinuation of specific site or of the study as a whole are handled as described in 
Section 10.1.8. 

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8. 
STUDY ASSESSMENTS AND PROCEDURES 
 Study procedures and their timing are summarized in the SoA (Table 1). Protocol 
waivers or exemptions are not allowed. 
 Immediate safety concerns should be discussed with Alexion immediately upon 
occurrence or awareness to determine if the participant should continue or 
discontinue study intervention. 
 Adherence to the study design requirements, including those specified in the SoA, is 
essential and required for study conduct. 
 All screening evaluations must be completed and reviewed to confirm that potential 
participants meet all eligibility criteria. The Investigator will maintain a screening log 
to record details of all participants screened and to confirm eligibility or record 
reasons for screen failure, as applicable. 
 Procedures conducted as part of the participa
(eg, blood count) and obtained before signing of the ICF may be utilized for 
screening or baseline purposes provided the procedures met the protocol-specified 
criteria and were performed within the time frame defined in the SoA. 
 Abnormal laboratory parameters may be repeated once during the Screening Period to 
ensure an accurate assessment of eligibility.  
 Unscheduled blood samples may be taken at the discretion of the Investigator for 
assessment of safety issues. 
8.1. 
Efficacy Assessments 
No efficacy assessments will be obtained during this study. 
8.2. 
Safety Assessments 
Planned time points for all safety assessments are provided in the SoA (Table 1). 
For study Periods 1 and 2, when multiple procedures are scheduled to occur at the same time, the 
following order of events should be strictly adhered to whenever possible: Vital signs, ECG, 
blood sampling, study intervention administration, and meal.  
Collection of samples for PK assessment should occur as close as possible to the scheduled time.  
8.2.1. 
Physical Examinations 
 A complete physical examination will include, at a minimum, assessments of the 
cardiovascular, respiratory, gastrointestinal, and neurological systems. It will be 
performed at Screening, Check-in for each period, and at the EOS or upon ET. 
Height, BMI (at Screening only) and weight will also be measured and recorded as 
outlined in the SoA (Table 1). 
 A symptom-driven physical examination may be performed at other times, at the 
 

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 Investigators should pay special attention to clinical signs related to previous serious 
illnesses. 
8.2.2. 
Vital Signs 
 Oral temperature, pulse rate, respiratory rate, and systolic and diastolic blood pressure 
(mm Hg) will be assessed. 
 Routine blood pressure and pulse measurements will be assessed with a completely 
automated device. Manual techniques should be used if repeat measurements are 
necessary due to abnormal results.  
 Blood pressure and pulse measurements should be preceded by at least 5 minutes of 
rest for the participant in a quiet setting without distractions (eg, television, cell 
phones). Ideally, the same arm for each participant should be used for measurements. 
8.2.3. 
Vital signs will be measured in a semi-supine position after 5 minutes rest. 
Electrocardiograms 
 Participants will be resting in the supine position for at least 15 minutes prior to and 5 
minutes after each nominal time point for ECG extraction. Triplicate 12-lead ECG 
will be conducted as outlined in the SoA (see Table 1 ) to obtain heart rate, PR, QRS, 
QT, and QTc intervals. Heart rate and interval data will be recorded in the eCRF. QT 
the QTc 
reading (unless unavailable and then QTcB may be recorded). Refer to Section 7 for 
QTc withdrawal criteria and any additional QTc readings that may be necessary. 
8.2.4. 
Clinical Safety Laboratory Assessments 
 See Section 10.2 for the list of clinical laboratory tests to be performed and the  SoA 
(Table 1) for the timing and frequency.  
 The Investigator must review the laboratory report, document this review, and record 
any clinically relevant changes occurring during the study in the AE section of the 
results. The laboratory reports must be filed with the source documents.  
 All laboratory tests with values considered clinically significantly abnormal during 
participation in the study after the last dose of the study intervention should be 
repeated until the values return to normal or baseline or are no longer considered 
clinically significant by the Investigator or Medical Monitor. 
 If such values do not return to normal/baseline within a period of time judged 
reasonable by the Investigator, the etiology should be identified, and Alexion 
notified. 
 All protocol-required laboratory assessments, as defined in Section 10.2, must be 
conducted in accordance with the laboratory manual and the SoA (Table 1). 
 All laboratory values from nonprotocol specified laboratory assessments also 
must be recorded in the CRF.  

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8.2.5. 
Suicidal Ideation and Behavior Risk Monitoring 
For bupropion, as stated in the WELLBUTRIN SR USPI (WELLBUTRIN SR), there is 
n, adolescents and young adults taking 
antidepressants. All patients should be monitored for worsening and emergence of suicidal 
(Table 1
 
8.2.6. 
Pregnancy 
 Pregnancy data from female participants and female spouses/partners of male 
participants will be collected from the first dose of the study intervention through 
90 days post the last dose and at the time points specified in the SoA. Any female 
participant who becomes pregnant while participating in the study will be 
discontinued from the study intervention. If a pregnancy is reported, the Investigator 
must immediately inform Alexion within 24 hours of awareness of the pregnancy and 
follow the procedures outlined in Section 10.4. 
 For all Alexion products, both in development or post-approval, exposure during 
pregnancy must be recorded and the pregnancy followed until the outcome of the 
pregnancy is known (ie, spontaneous miscarriage, elective termination, normal birth, 
or congenital abnormality), even if the participant discontinues study intervention or 
withdraws from the study. The corresponding infant must be followed for 3 months 
postpartum. 
 Pregnancy is not considered an AE (Section 10.4) unless there is a suspicion that the 
study intervention may have interfered with the effectiveness of a contraceptive 
medication. However, complications of pregnancy and abnormal outcomes of 
pregnancy are AEs and may meet the criteria for a SAE (eg, ectopic pregnancy, 
spontaneous abortion, intrauterine fetal demise, neonatal death, or congenital 
anomaly) (Section 8.3). Elective abortions without complications should not be 
reported as AEs. 
8.3. 
Adverse Events and Serious Adverse Events 
The definitions of AEs and SAEs can be found in Section 10.3. 
Adverse events will be reported to the Investigator or qualified designee by the participant 
(or, when appropriate, by a caregiver, surrogate, or 
representative). 
The Investigator and any qualified designees are responsible for detecting, documenting, and 
recording events that meet the definition of an AE or SAE and remain responsible for following 
up AEs that are serious, considered related to the study intervention or study procedures, or that 
caused the participant to discontinue the study (see Section 7). 
Procedures for recording, evaluating, follow-up, and reporting AEs and SAEs are outlined in 
Section 10.3. 

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8.3.1. 
Time Period and Frequency for Collecting Adverse Event and Serious Adverse 
Event Information 
All AEs will be collected from the signing of the ICF until the EOS or ET Visit.  
All SAEs will be recorded and reported to Alexion or the designee immediately and under no 
circumstance should this exceed 24 hours, as indicated in Section 10.3. The Investigator will 
submit any updated SAE data to Alexion within 24 hours of it being available. 
Investigators are not obligated to actively seek AEs or SAEs after conclusion of the study 
participation. However, if the Investigator learns of any SAE, including a death, at any time after 
a participant has exited the study, and he/she considers the event to be reasonably related to the 
study intervention, the Investigator must promptly notify Alexion. 
8.3.2. 
Method of Detecting AEs and SAEs 
The method of recording, evaluating, and assessing causality of AEs and SAEs and the 
procedures for completing and transmitting SAE reports are provided in Section 10.3.  
Care will be taken not to introduce bias when detecting AEs and/or SAEs. Open-ended and 
non-leading verbal questioning of the participant is the preferred method to inquire about 
AE occurrences. 
8.3.3. 
Follow-up of AEs and SAEs 
After the initial AE/SAE report, the Investigator is required to proactively follow-up with each 
participant at subsequent visits/contacts. All SAEs will be followed until resolution, stabilization, 
the event is otherwise explained, or the participant is lost to follow-up (as defined in 
Section 7.3). Further information on follow-up procedures is provided in Section 10.3.  
8.3.4. 
Regulatory Reporting Requirements for SAEs 
 Prompt notification by the Investigator to Alexion of an SAE is essential so that legal 
obligations and ethical responsibilities towards the safety of participants and the 
safety of a study intervention under clinical investigation are met. 
 Alexion has a legal responsibility to notify both the local regulatory authority and 
other regulatory agencies about the safety of a study intervention under clinical 
investigation. Alexion will comply with country-specific regulatory requirements 
relating to safety reporting to the regulatory authority, Institutional Review Boards 
(IRBs)/Independent Ethics Committees (IECs), and Investigators. 
 Suspected unexpected serious adverse reactions (SUSARs) must be reported 
according to local regulatory requirements and Alexion policy and forwarded to 
Investigators as necessary. 
 An Investigator who receives an Investigator Safety Report describing an SAE or 
other specific safety information (eg, summary or listing of SAEs) from Alexion will 
review and then file it along with the IB and will notify the IRB/IEC, if appropriate 
according to local requirements. 

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8.3.5. 
Adverse Events of Special Interest 
There are no adverse events of special interest for this study. 
8.3.6. 
Retained and Biobanked Sample 
A single biobanked serum sample will be collected pre-dose to serve as a retained safety sample 
during the study. At the end of the study, pre-dose safety samples will be biobanked to support 
assay development and determination of normal Cu and Mo levels in healthy participants. 
Samples may be stored and used for up to 5 years following completion of the study. 
8.4. 
Treatment of Overdose 
For this study, any dose of ALXN1840 or bupropion greater than that specified in the protocol 
will be considered an overdose. 
Alexion does not recommend specific treatment for an overdose.  
Overdoses are medication errors that are not considered AEs unless there is an untoward medical 
occurrence resulting from the overdose. 
In the event of an overdose or suspected overdose, the Investigator or treating physician should: 
 Contact the Medical Monitor immediately. 
 Closely monitor the participant for any AE/SAE. 
 Obtain a plasma sample for PK analysis if requested by the Medical Monitor (determined 
on a case-by-case basis).  
 Document the quantity of the excess dose as well as the duration of the overdose in the 
CRF. 
Decisions regarding dose interruptions or modifications will be made by the Investigator in 
consultation with the Medical Monitor based on the clinical evaluation of the participant. 
8.5. 
Pharmacokinetics 
 Whole blood samples will be collected for the measurement of plasma concentrations 
of total Mo, bupropion and its metabolite hydroxybupropion as specified in the SoA 
(Table 1). Additional samples may be collected at additional time points during the 
study if warranted and agreed upon between the Investigator and Alexion. Collection 
of samples for PK evaluation should occur as close as possible to the scheduled time 
and actual time of collection should be documented on the eCRF. Samples collected 
within ± 10% of the scheduled time or 30 minutes, whichever is less, will not be 
considered a protocol deviation. In the event of a safety occurrence and after 
agreement between the Investigator and Medical Monitor, up to 3 additional PK 
sampling timepoints may be added.  
 Instructions for the collection and handling of biological samples will be provided by 
Alexion. The actual date and time (24-hour clock time) of each sample will be 
recorded. 

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 Samples will be used to evaluate the effect of ALXN1840 on the PK of bupropion. 
Samples collected for analyses of plasma concentrations may also be used to evaluate 
safety or efficacy aspects related to concerns arising during or after the study. 
 Excess/additional samples may be stored for up to 5 years and used for 
pharmacodynamic (PD) development and research to understand the pathways 
associated with the mechanism of action of ALXN1840; however, samples will not 
be used for genetic analyses (ie RNA or DNA analyses).  
8.6. 
Pharmacodynamics 
Plasma samples collected for PK may be used for analyzing the PD of ALXN1840 including, but 
not limited to plasma total Cu, ceruloplasmin (Cp), Cp-bound Cu (CpC), and potentially toxic Cu 
measured as labile-bound Cu (LBC) and PUF Cu and/or NCC/NCCcorrected. 
8.7. 
Genetics 
Blood samples for genetic testing of CYP2B6 polymorphism will be collected at clinical 
Check-in (Day -1). This study proposes to collect genetic polymorphism data to characterize 
potential impact of ALXN1840 on phenotypic CYP2B6 metabolism of bupropion and evaluate 
the potential effect of genetic polymorphism on the between-participant variability of bupropion 
PK. As this is an exploratory assessment, the study will not specifically select target participants 
with a certain proportion of CYP2B6 genotypes. 
8.8. 
Biomarkers 
Biomarkers are not evaluated in this study.  
8.9. 
Immunogenicity 
Not applicable. 
8.10. 
Health Economics and Medical Resource Utilization 
Health economic and medical resource utilization parameters are not evaluated in this study. 

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9. 
STATISTICAL CONSIDERATIONS 
9.1. 
Statistical Hypotheses 
The primary objective is to determine the effect of ALXN1840 on the PK of bupropion. There is 
no formal null hypothesis to be statistically tested and used to drive declaration of study success 
or failure.  
To assure the study has enough participants, to estimate the inhibitory effect of ALXN1840 on 
the metabolism of bupropion with adequate precision, the sample size was determined using the 
conservative 90% confidence interval (CI) and 80% to 125% no-effect boundary approach 
ug Interaction Studies 
 Cytochrome P450 
Enzyme- 
o 125 
ce should be taken into consideration when determining the clinical 
stimated inhibition effect of 
ALXN1840 on bupropion PK lies outside this no-effect boundary, this should not be interpreted 
as a failed study. 
9.2. 
Sample Size Determination 
A default of no-effect boundary (80% to 125%) approach will be employed to assess whether 
there is an inhibition effect on the metabolism of bupropion in the presence of ALXN1840. For a 
2 -period crossover study design, assuming the true ratio of the means (bupropion + ALXN1840 
vs bupropion alone) on the PK parameters is 1 (Cmax; area under the plasma concentration versus 
time curve from zero to infinity [AUC ]) and the bupropion intra-participant coefficient of 
variation (CV) is 0.30 (Dennison, 2018), a total sample size of 32 completed participants can 
achieve 90% power with two 1-sided tests, each with a type I error rate of 5% (two-sided type I 
error rate of 10%). The intra-participant CV is estimated using residual mean-square error (MSE) 
- 1) for the 
log-transformed PK parameters. 
Assuming a 15% dropout rate, approximately 38 participants were planned to be enrolled and 
randomized in the original protocol. This protocol amendment is increasing the planned 
enrollment number because 17 of the 31 randomized participants (as of the date of this 
amendment) were anticipated to not have viable PK samples (pending further bioanalytical 
stability investigation) following a power outage at the CRU during study conduct. To reach the 
sample size of 32 completed participants necessary for sufficient study power as previously 
described, an additional 21 participants will be randomized to complete at least 18 of the 21 
(assuming a similar 15% dropout rate for the additionally enrolled participants). Therefore, a 
total of approximately 52 participants will now be randomized in this study to still reach the aim 
of at least 32 completed participants.  
9.3. 
Populations for Analyses 
The following populations are defined (Table 6): 

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Table 6: 
Populations for Analyses 
Population 
Description 
Enrolled Set 
All participants who sign the ICF 
Safety Set 
All participants who receive at least 1 dose of study intervention 
Pharmacokinetic/Pharmacodynamic 
(PK/PD) Analysis Set 
All participants who have sufficient plasma samples to have evaluable PK 
data for bupropion and total Mo (as a measure of ALXN1840) in plasma 
Abbreviation: ICF = informed consent form; Mo = molybdenum. 
9.4. 
Statistical Analyses 
Statistical methods described in this section will be further elaborated in a separate Statistical 
Analysis Plan (SAP). The SAP will be developed and approved before database lock and will 
describe the participant populations to be included in the analyses, and procedures for accounting 
for missing data. 
Summary statistics will be computed and displayed by study group and by visit, where 
applicable. Descriptive statistics for continuous variables will include number of non-missing 
values, arithmetic mean, standard deviation, median, minimum, and maximum. Categorical 
variables will be summarized using percentages and frequency counts.  
All statistical analyses will be conducted using SAS® for Windows® Version 9.3 or higher. 
9.4.1. 
Efficacy Analyses 
No efficacy analyses will be performed for this study. 
9.4.2. 
Safety Analyses 
All safety analyses will be performed on the Safety Set.  
Safety analyses will include an analysis of all AEs, ECGs, clinical laboratory data, physical 
examinations, and vital sign measurements using descriptive statistics. Data will be summarized 
by study groups.  
No inferential statistical analyses are planned for the safety parameters of this study. The 
incidence of AEs and SAEs will be summarized by System Organ Class (SOC) and Preferred 
Term for each treatment and overall, and by relationship to study intervention. Adverse events 
will also be summarized by treatment and overall by severity. Serious AEs and AEs resulting in 
withdrawal from the study will be listed. Participants having multiple AEs within a category 
(eg, overall, SOC, Preferred Term) will be counted once in that category. For severity tables, a 
s most severe event within a category will be counted.  
Changes from baseline in vital sign measurements and laboratory assessments (eg, chemistry, 
blood cell count with differential, and urinalysis) will be summarized by study groups. 
Laboratory parameter values will be graded according to the National Cancer Institute Common 
Terminology Criteria for Adverse Events (CTCAE). Shift tables by treatment will be produced 
for these laboratory parameters. These tables will summarize the number of participants with 
each baseline grade relative to the reference ranges and changes to the worst highest grade 
assessed postdose during the study.  

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Electrocardiogram parameters will be measured at the specified time points, including heart rate, 
PR, RR, QRS, QT, and corrected QTcF intervals. The average of the triplicate ECG readings at 
the time points collected will be calculated, and changes from pretreatment baseline values will 
be assessed by each treatment.  
All concomitant medications will be coded and summarized using the World Health 
Organization (WHO) Drug Dictionary. 
9.4.3. 
Other Analyses 
9.4.3.1. 
Pharmacokinetic and Pharmacodynamic Analyses 
Pharmacokinetic analyses will be performed using the PK/PD Analysis Set. 
Blood samples for PK analysis of total Mo (as a measure of ALXN1840), bupropion and its 
metabolite, hydroxybupropion will be collected at the following time points: pre-dose and 
post-dose at 1, 2, 3, 4, 5, 6, 8, 12, 24, 48, 72, 96, 120, 144, 168, 192, 216, 240, and 336 hours in 
each period (Note: the 336 hours sample in Period 1 will be collected during the Period 2, 
Pre-dose [Day 1] Visit). 
The following plasma PK parameters will be calculated as endpoints for total Mo, bupropion and 
hydroxybupropion using noncompartmental methods with Phoenix® WinNonlin® (Certara USA 
Inc., Princeton, New Jersey) Version 8.0 or higher or SAS Version 9.3 or higher (SAS Institute 
Inc., Cary, North Carolina), as applicable. Calculations will be based on the actual sampling 
times recorded during the study. 
 Time delay between the time of dosing and time of appearance of drug concentration 
in plasma (Tlag; for plasma total Mo with ALXN1840 administration) 
 Maximum observed concentration in plasma (Cmax) 
 Time to Cmax (Tmax)   
 Area under the plasma concentration (AUC) versus time curve from time 0 to the last 
quantifiable concentration (AUCt) 
 AUC versus time curve from time 0 to infinity (AUC )  
 AUC extrapolated from time t to infinity as a percentage of total AUC  (%AUCextrap)  
 Apparent terminal-
z) 
 Terminal elimination half-life (t½) 
 Apparent oral clearance (CL/F) 
 Apparent volume of distribution (Vd/F) 
 Metabolite to parent ratio based on AUC (MRAUC) and Cmax (MRCmax) [estimated 
for bupropion and hydroxybupropion] 
Additional plasma PK parameters may be calculated if deemed appropriate. 
Plasma concentrations of total Mo, bupropion and hydroxybupropion and time deviation data 
will be presented in a data listing by participant. Plasma concentration data will be summarized 

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separately by analyte and time point for each treatment using the following descriptive statistics: 
number of participants, arithmetic mean, SD, coefficient of variation (CV), median, minimum, 
and maximum. Mean plasma concentration versus scheduled time profiles will be presented in 
figures on both linear and semilogarithmic scales. Individual plasma concentration versus actual 
time profiles will be presented similarly. 
Pharmacokinetic parameters derived from plasma concentrations of total Mo, bupropion and 
hydroxybupropion will be presented in data listings and summarized separately using the 
following descriptive statistics: number of participants, arithmetic mean, SD, arithmetic CV, 
median, minimum, maximum, and 95% CI. Geometric mean and geometric CV will be presented 
for Cmax and AUCs only. 
The effect of ALXN1840 on the 
model (SAS PROC MIXED) with treatment condition, sequence, and period as fixed effects and 
med PK parameters Cmax, AUC  and AUCt for estimation of effects and construction 
of CIs for the test treatment (Treatment B: 150 mg bupropion + 60 mg ALXN1840) compared 
with the reference treatment (Treatment A: 150 mg bupropion). The within-participant CV for 
the corresponding PK parameters will be estimated using the mean squared error from the 
statistical model. Confidence intervals (90%) will be constructed for the least-squares geometric 
mean ratio (GMR) estimates between the test and reference treatments for above PK parameters 
using the natural log-transformed data. The GMR estimates and the associated 90% confidence 
limits will be exponentiated back to the original scale. These analyses will be repeated to assess 
the effect of ALXN1840 on hydroxybupropion PK. 
Analyses of other PK data including, but not limited to PUF Mo may be conducted. 
Pharmacodynamic data of ALXN1840 including, but not limited to, plasma total Cu, Cp, CpC, 
and potentially toxic Cu measured as LBC and PUF Cu and/or assessed via NCC/NCCcorrected 
may be analyzed and reported. 
Details of the PK/PD analyses will be described in the PK/PD data analysis plan or included in 
the SAP, which will be finalized before database lock. 
9.5. 
Interim Analyses  
No interim analyses are planned for this study. 
9.6. 
Data Monitoring Committee 
There will not be a Data Monitoring Committee, but provision is included for an ad hoc Safety 
Review Committee (SRC), if needed. 
9.7. 
Safety Review Committee 
To ensure participant safety, ad hoc SRC meetings may be held to discuss urgent issues should 
the need arise. The ad hoc SRC must convene within 24 hours in the case of a TESAE or the 
withdrawal of any participant due to an adverse reaction. 

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The ad hoc SRC, consisting of the Investigator, Alexion Safety Physician and Alexion Medical 
Monitor will evaluate the study data, if needed, for participant safety and make recommendations 
on termination of the study.  

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10. 
SUPPORTING DOCUMENTATION AND OPERATIONAL 
CONSIDERATIONS 
10.1. 
Appendix 1: Regulatory, Ethical, and Study Oversight 
Considerations 
10.1.1. 
Regulatory and Ethical Considerations 
 This study will be conducted in accordance with the protocol and with the following: 
 Consensus ethical principles derived from international guidelines including the 
Declaration of Helsinki and Council for International Organizations of Medical 
Sciences (CIOMS) International Ethical Guidelines 
 Applicable International Council for Harmonisation (ICH) Good Clinical Practice 
(GCP) Guidelines 
 Applicable laws and regulations 
 The protocol, protocol amendments, ICF, IB, and other relevant documents 
(eg, advertisements) must be submitted to an IRB/IEC by the Investigator and 
reviewed and approved by the IRB/IEC before the study is initiated.  
 Any amendments to the protocol will require IRB/IEC approval and, where 
applicable, competent authority approval before implementation of changes made to 
the study design, except for changes necessary to eliminate an immediate hazard to 
study participants.  
 The Investigator will be responsible for the following: 
 Providing written summaries of the status of the study to the IRB/IEC annually or 
more frequently in accordance with the requirements, policies, and procedures 
established by the IRB/IEC. 
 Notifying the IRB/IEC of SAEs or other significant safety findings as required by 
IRB/IEC procedures. 
 Providing oversight of the conduct of the study at the site and adherence to 
requirements of 21 Code of Federal Regulations (CFR), ICH guidelines, the 
IRB/IEC, European regulation 536/2014 for clinical studies (if applicable), and all 
other applicable local regulations. 
10.1.2. 
Financial Disclosure 
Investigators and Sub-Investigators will provide Alexion with sufficient, accurate financial 
information as requested to allow Alexion to submit complete and accurate financial certification 
or disclosure statements to the appropriate regulatory authorities. Investigators are responsible 
for providing information on financial interests during the course of the study and for 1 year after 
completion of the study. 

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10.1.3. 
Informed Consent Process 
 It is the responsibility of the Investigator to obtain signed (written or electronic 
signature) informed consent from all study participants prior to any study-related 
procedures including screening assessments. 
 The Investigator or his/her representative will explain the nature of the study 
(including but not limited to the objectives, potential benefits and risk, 
defined according to local and country regulations where the study is taking place, 
and answer all questions regarding the study.  
 Participants must be informed that their participation is voluntary. Participants, or 
their legally authorized representative, will be required to sign a statement of 
informed consent that meets the requirements of 21 CFR 50, local regulations, 
European Union (EU) General Data Protection Regulation (GDPR), ICH guidelines, 
Health Insurance Portability and Accountability Act (HIPAA) requirements, where 
applicable, and the IRB/IEC or study center.  
 The medical record must include a statement that written informed consent was 
obtained before the participant was screened in the study and the date the written 
consent was obtained. The authorized person obtaining the informed consent must 
also sign the ICF(s). 
 Participants must be re-consented to the most current version of the ICF(s) during 
their participation in the study.  
 A copy of the signed (written or electronic) documentation (ie, a complete set of 
participant information sheets and fully executed signature pages) must be provided 
epresentative, as applicable. 
This document may require translation into the local language. Signed (written or 
electronic) consent forms must remain in each pa
available for verification at any time. 
 The ICF will contain a separate section that addresses the use of remaining mandatory 
samples for optional exploratory research. The Investigator or authorized designee 
will explain to each participant the objectives of the exploratory research. If sharing 
exploratory research results with the Investigator is not planned, the ICF should 
mention it. Participants or legally authorized representative will be told that they are 
free to refuse to participate and may withdraw their consent at any time and for any 
reason during the storage period. A separate signature will be required to document a 
research. Participants who decline to participate in this optional research will not 
provide this separate signature. 
10.1.4. 
Data Protection 
 Participants will be assigned a unique identifier by Alexion. Any participant records 
or datasets that are transferred to Alexion will contain the identifier only; participant 

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names or any information which would make the participant identifiable will not be 
transferred.  
 The participant must be informed that his/her personal study-related data will be used 
by Alexion in accordance with local data protection law. The level of disclosure must 
also be explained to the participant who will be required to give consent for their data 
to be used as described in the informed consent.  
 The participant must be informed that his/her medical records may be examined by 
Clinical Quality Assurance auditors or other authorized personnel appointed by 
Alexion, by appropriate IRB/IEC members, and by inspectors from regulatory 
authorities. 
10.1.5. 
Dissemination of Clinical Study Data 
Study-related information and study results may be posted on publicly accessible clinical study 
databases (eg, the US website www.clinicaltrials.gov or the EU website 
www.clinicaltrialregister.eu), as appropriate, and in accordance with national, regional, and local 
regulations. 
10.1.6. 
Data Quality Assurance 
 All participant data relating to the study will be recorded on a printed or electronic 
CRF unless transmitted to Alexion or designee electronically (eg, laboratory data). 
The Investigator is responsible for verifying that data entries are accurate and correct 
by physically or electronically signing the CRF.  
 The Investigator must maintain accurate documentation (source data) that supports 
the information entered in the CRF.  
 The Investigator must permit study-related monitoring, audits, IRB/IEC review, and 
regulatory agency inspections and provide direct access to source data documents.  
 Alexion or its designee is responsible for the data management of this study including 
quality checking of the data.  
 Study monitors will perform ongoing source data verification to confirm that data 
entered into the CRF by authorized site personnel are accurate, complete, and 
verifiable from source documents; that the safety and rights of participants are being 
protected; and that the study is being conducted in accordance with the currently 
approved protocol and any other study agreements, ICH GCP, and all applicable 
regulatory requirements.  
 Records and documents, including signed ICFs, pertaining to the conduct of this 
study must be retained by the Investigator for 2 years after the last marketing 
application approval, or if not approved, 2 years following the discontinuance of the 
test article for investigation, unless local regulations or institutional policies require a 
longer retention period. No records may be destroyed during the retention period 
without the written approval of Alexion. No records may be transferred to another 
location or party without written notification to Alexion.  

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10.1.7. 
Source Documents 
Source documents provide evidence for the existence of the participant and substantiate the 
integrity of the data collected. The Investigator or designee will prepare and maintain adequate 
and accurate source documents (eg, medical records, ECGs, AE and concomitant medication 
reporting, raw data collection forms) designed to record all observations and other pertinent data 
for each participant. 
Data reported in the CRF that are transcribed from source documents must be consistent with the 
source documents or the discrepancies must be explained. The Investigator may need to request 
previous medical records or transfer records, depending on the study. Also, current medical 
 
10.1.8. 
Study and Site Start and Closure 
The study start date is the date on which the first participant signs the informed consent.  
Alexion or its designee reserves the right to close the study site or terminate the study at any time 
for any reason at the sole discretion of Alexion. Study sites will be closed upon study 
completion. A study site is considered closed when all required documents and study supplies 
have been collected and a study site closure visit has been performed. 
The Investigator may initiate study site closure at any time, provided there is reasonable cause 
and sufficient notice is given in advance of the intended termination. 
Reasons for the early closure of a study site by Alexion or the Investigator may include but are 
not limited to: 
 Failure of the Investigator to comply with the protocol, the requirements of the 
IRB/IEC or local health authorities, Alexion 
 GCP guidelines. 
 Inadequate recruitment of participants by the Investigator. 
 Discontinuation of further study intervention development. 
If the study is prematurely terminated or suspended, Alexion shall promptly inform the 
Investigators, the IECs/IRBs, the regulatory authorities, and any contract research 
organization(s) used in the study of the reason for termination or suspension, as specified by the 
applicable regulatory requirements. The Investigator shall promptly inform the participant and 
should assure appropriate therapy and/or follow-up. 
10.1.9. 
Publication Policy 
 Where possible, primary manuscripts reporting results of the primary efficacy 
endpoint or the final results will be submitted for publication within 12-18 months of 
the primary evaluation date or end of study, whichever is earlier.  
 Investigators who participate as authors in manuscripts derived from 
Alexion-sponsored studies will agree to the prerequisites as outlined in the Alexion 
author engagement agreement prior to engaging in manuscript development.  
 The Investigator agrees to submit proposals for new manuscripts (whether or not the 
proposed analyses are derived from protocol-specified endpoints) to Alexion for 

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review and consideration. All manuscripts or abstracts emanating from approved 
proposals are to be submitted to Alexion for review before submission to the 
journal/society. This allows Alexion to protect proprietary information and to provide 
comments.  
 The proprietary nature of some development work may preclude publication. In 
some cases, it may be necessary to delay a publication to allow Alexion to ensure 
protection of intellectual property.  
 In general, primary publications, including congress and journal publications, 
containing the protocol-specified results of a study should occur prior to the 
duplicate publication, whereby the same results must not be published in multiple 
peer-reviewed journal manuscripts.  
 Encore congress publications may be appropriate to allow communication of 
research findings to relevant audience and geographical regions. 
 Alexion will comply with the requirements for publication of study results. In 
accordance with standard editorial and ethical practice, Alexion will generally 
support publication of multicenter studies only in their entirety and not as individual 
site data. In this case, a coordinating Investigator will be designated by mutual 
agreement. 
 Authorship will be determined by mutual agreement and in line with International 
Committee of Medical Journal Editors authorship requirements and per the Alexion 
Publication Policy. 

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10.2. 
Appendix 2: Clinical Laboratory Tests 
 The tests detailed in Table 7 be performed by the local laboratory.  
 Protocol-specific requirements for inclusion or exclusion of participants are detailed 
in Section 5 of the protocol.  
 Additional tests may be performed at any time during the study as determined 
necessary by the Investigator or required by local regulations. Investigators must 
document their review of each laboratory safety report and indicate whether out of 
range results are cl
 
 Women of childbearing potential should only be enrolled after a negative serum 
pregnancy test result at screening. Additional urine pregnancy testing will be standard 
for the protocol unless serum testing is required by site policies, local regulation, or 
IRB/IEC and should be performed per the time points specified in the SoA (Table 1 ). 
Screening pregnancy criteria are detailed in Section 5.1. 
Table 7: 
Protocol-Required Safety Laboratory Assessments 
Laboratory 
Assessments 
Parameters 
Hematology 
Platelet Count 
Red blood cell count 
Hemoglobin 
Hematocrit 
RBC Indices: 
Mean corpuscular volume 
Mean corpuscular hemoglobin 
% Reticulocytes 
WBC count with 
differential: 
Neutrophils 
Lymphocytes 
Monocytes 
Eosinophils 
Basophils 
Clinical Chemistry 
BUN 
Potassium 
Bicarbonate 
Sodium 
Glucose 
AST 
ALT 
Chloride 
Alkaline phosphatase 
Direct bilirubin 
Total bilirubin 
Albumin 
Creatinine 
Creatine phosphokinase 
Coagulation 
INR  
Partial thromboplastin time 
Prothrombin time 
Routine Urinalysis 
Specific gravity 
pH 
Glucose 
Protein 
Blood 
Bilirubin 
Urobilinogen 
Nitrite 
Leukocyte esterase by dipstick 
Microscopic examination

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Table 7: 
Protocol-Required Safety Laboratory Assessments 
Laboratory 
Assessments 
Parameters 
Other Screening 
Tests 
Urine alcohol and urine drug screen (to include at minimum: amphetamines, 
barbiturates, benzodiazepines, cocaine, opiates, phencyclidine, methamphetamine, 
3,4-methylenedioxy-methamphetamine, methadone, and tetrahydrocannabinol 
[cannabinoids])  
 
Human immune deficiency virus (HIV)-1 and HIV-2 antibodies, HbsAg a, anti-HBC IgG 
+ IgM (if IgG positive), and anti- HCV with confirmation by HCV RNA  
Serum or urine hCG pregnancy test (as needed for women of childbearing potential) 
 FSH (postmenopausal females only) 
 3 × 
 2 × ULN (> 35% direct bilirubin) or 
 3 × ULN and international normalized ratio (INR) > 1.5, if INR measured which may indicate severe liver 
 
a Only HBsAg testing is necessary for exclusion of active HBV infection; anti-HBC laboratory collection is not 
required. 
Abbreviations: ALT = alanine aminotransferase; AST = aspartate aminotransferase; BUN = blood urea nitrogen; 
FSH = follicle-stimulating hormone; HbsAg = hepatitis B surface antigen; HbA1C = hemoglobin A1C;  
HBC = hepatitis B core antigen; hCG = human chorionic gonadotropin; HCV = hepatitis C virus; HIV = human 
immunodeficiency virus; Ig = immunoglobulin; INR = international normalized ratio; RBC = red blood cell; 
RNA = ribonucleic acid; WBC = white blood cell. 
Investigators must document their review of each laboratory safety report. 
 

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10.3. 
Appendix 3: Adverse Events: Definitions and Procedures for 
Recording, Evaluating, Follow-up, and Reporting 
10.3.1. 
Definition of AE 
AE Definition 
 
An AE is any untoward medical occurrence in a participant, temporally associated with the use of study 
intervention, whether or not considered related to the study intervention. 
 
Note: An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory 
finding), symptom, or disease (new or exacerbated) temporally associated with the use of study intervention. 
 
Events Meeting the AE Definition  
 
Any abnormal laboratory test results (hematology, clinical chemistry, or urinalysis) or other safety 
assessments (eg, ECG, radiological scans, vital signs measurements), including those that worsen from 
baseline, considered clinically significant in the medical and scientific judgment of the Investigator. 
 
Exacerbation of a chronic or intermittent pre-existing condition including either an increase in frequency 
and/or intensity of the condition. 
 
New conditions detected or diagnosed after study intervention administration even though it may have been 
present before the start of the study. 
 
Signs, symptoms, or the clinical sequelae of a suspected drug-drug interaction. 
 
Signs, symptoms, or the clinical sequelae of a suspected overdose of either study intervention or a 
concomitant medication. Overdose per se will not be reported as an AE/SAE unless it is an intentional 
overdose taken with possible suicidal/self-harming intent. Such overdoses should be reported regardless of 
sequelae. 
 
Events Not Meeting the AE Definition  
 
Medical or surgical procedure (eg, endoscopy, appendectomy): The condition that leads to the procedure is 
the AE. Situations in which an untoward medical occurrence did not occur (eg, hospitalization for elective 
surgery if planned before the signing the ICF, admissions for social reasons or for convenience).  
 
Anticipated day-to-day fluctuations of pre-existing disease(s) or condition(s) present or detected at the start of 
the study that do not worsen.  
 
A medication error (including intentional misuse, abuse, and overdose of the product) or use other than what 
is defined in the protocol is not considered an AE unless there is an untoward medical occurrence as a result 
of a medication error.  
 
Cases of pregnancy that occur during maternal or paternal exposure to study intervention are to be reported 
within 24 hours of Investigator/site awareness. Data on fetal outcome and breastfeeding will be collected for 
regulatory reporting and safety evaluation.  
 
Situations in which an untoward medical occurrence did not occur (social and/or convenience admission to a 
hospital).
10.3.2. 
Definition of SAE 
If an event is not an AE per definition above, then it cannot be an SAE even if serious conditions 
are met (eg, hospitalization for signs/symptoms of the disease under study, death due to 
progression of disease). 
An SAE is defined as any untoward medical occurrence that, at any dose: 
1. Results in death 
2. Is life-threatening 

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An SAE is defined as any untoward medical occurrence that, at any dose: 
-threa
death at the time of the event. It does not refer to an event, which hypothetically might have caused death, if it 
was more severe. 
3. Requires inpatient hospitalization or prolongation of existing hospitalization 
In general, hospitalization signifies that the participant has been detained (usually involving at least an overnight 
stay) at the hospital or emergency ward for observation and/or treatment that would not have been appropriate in 
complication prolongs hospitalization or fulfills any other serious criteria, the event is serious. When in doubt as 
 
Hospitalization for elective treatment of a pre-existing condition that did not worsen from baseline is not 
considered an AE. 
4. Results in persistent disability/incapacity 
 
The ter
 
 
This definition is not intended to include experiences of relatively minor medical significance such as 
uncomplicated headache, nausea, vomiting, diarrhea, influenza, and accidental trauma (eg, sprained ankle) 
which may interfere with or prevent everyday life functions but do not constitute a substantial disruption. 
5. Is a congenital anomaly/birth defect 
6. Other situations: 
 
Medical or scientific judgment should be exercised in deciding whether SAE reporting is appropriate in 
other situations such as important medical events that may not be immediately life-threatening or result in 
death or hospitalization but may jeopardize the participant or may require medical or surgical intervention to 
prevent one of the other outcomes listed in the above definition. These events should usually be considered 
serious. 
 
Examples of such events include invasive or malignant cancers, intensive treatment in an emergency room 
or at home for allergic bronchospasm, blood dyscrasias or convulsions that do not result in hospitalization, 
or development of drug dependency or drug abuse. 
10.3.3. 
Recording and Follow-Up of AE and/or SAE 
Recording of AE and/or SAE 
 
When an AE/SAE occurs, it is the responsibility of the Investigator to review all documentation (eg, hospital 
progress notes, laboratory reports, and diagnostics reports) related to the event. 
 
The Investigator will then record all relevant AE/SAE information in the CRF. 
 
It is not acceptabl
in lieu of completion of the AE/SAE CRF page. 
 
There may be instances when copies of medical records for certain cases are requested by Alexion. In this 
case, all participant identifiers, with the exception of the participant number, will be redacted on the copies 
of the medical records before submission to Alexion. 
 
The Investigator will attempt to establish a diagnosis of the event based on signs, symptoms, and/or other 
clinical information. Whenever possible, the diagnosis (not the individual signs/symptoms) will be 
documented as the AE/SAE.
Assessment of Intensity 
The Investigator will make an assessment of intensity for each AE and SAE reported during the study and assign 
it to one of the following categories from National Cancer Institute CTCAE v5.0, published 27 Nov 2017:  
 
Grade 1: Mild (awareness of sign or symptom, but easily tolerated) 
 
Grade 2: Moderate (discomfort sufficient to cause interference with normal activities) 
 
Grade 3: Severe (incapacitating, with inability to perform normal activities) 
 
Grade 4: Life-threatening 
 
Grade 5: Fatal
 

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Assessment of Causality 
 
The Investigator is obligated to assess the relationship between the study intervention and each occurrence 
of each AE or SAE. An Investigator causality assessment must be provided for all AEs (both nonserious and 
serious). This assessment must be recorded in the CRF and on any additional forms, as appropriate. The 
definitions for the causality assessments are as follows: 
 
Not related: There is no reasonable possibility the study intervention caused the AE.  
 
The AE has a more likely alternative etiology; it may be due to underlying or 
concurrent illness, complications, concurrent treatments, or effects of another 
concurrent drug.  
 
The event does not follow a reasonable temporal relationship to administration of the 
study intervention. 
 
Related: There is a reasonable possibility the study intervention caused the AE. 
 
The AE has a temporal relationship to the administration of the study intervention. 
 
The event does not have a likely alternative etiology.  
 
The event corresponds with the known pharmaceutical profile of the study 
intervention. 
 
There is improvement on discontinuation and/or reappearance on rechallenge. 
 
The Investigator will use clinical judgment to determine the relationship. 
 
Alternative causes, such as underlying disease(s), concomitant therapy, and other risk factors, as well as the 
temporal relationship of the event to study intervention administration will be considered and investigated. 
 
 
 
For each AE/SAE, the Investigator must document in the medical notes that he/she has reviewed the 
AE/SAE and has provided an assessment of causality. 
 
There may be situations in which an SAE has occurred, and the Investigator has minimal information to 
include in the initial report to Alexion. However, it is very important that the Investigator always make an 
assessment of causality for every event before the initial transmission of the SAE data to Alexion. 
 
The Investigator may change his/her opinion of causality in light of follow-up information and send an SAE 
follow-up report with the updated causality assessment. 
 
The causality assessment is one of the criteria used when determining regulatory reporting requirements.
 
Follow-up of AEs and SAEs 
 
The Investigator is obligated to perform or arrange for the conduct of supplemental measurements and/or 
evaluations as medically indicated or as requested by Alexion to elucidate the nature and/or causality of the 
AE or SAE as fully as possible. This may include additional laboratory tests or investigations, 
histopathological examinations, or consultation with other health care professionals. 
 
If a participant dies during participation in the study or during a recognized follow-up period, the 
Investigator will provide Alexion with a copy of any post-mortem findings including histopathology. 
 
New or updated information will be recorded in the originally completed CRF. 
 
The Investigator will submit any updated SAE data to Alexion within 24 hours of receipt of the 
information.

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10.3.4. 
Reporting of SAEs  
SAE Reporting to Alexion GDS via Paper Safety Reporting Form 
 
All SAEs will be recorded and reported to Alexion or designee immediately and within 24 hours 
awareness. 
 
SAEs will be reported using the Safety Reporting Form and submitted to Alexion Global Drug Safety 
(GDS). The Investigator must complete, sign, and date the SAE pages, verify the accuracy of the 
information recorded on the SAE pages with the corresponding source documents, and send a copy via 
email or facsimile to the contact information provided below: 
 
Email: clinicalsae@alexion.com or Fax: + 1.203.439.9347 
 
Additional follow-up information, if required or available, should be entered into the CRF and sent to 
Alexion GDS within 24 hours of the Investigator or study site staff becoming aware of this additional 
information via the reporting process outlined above.  
 
For all SAEs, the Investigator must provide the following: 
 
Appropriate and requested follow-up information in the time frame detailed above 
 
Causality of the SAE(s) 
 
Treatment of/intervention for the SAE(s) 
 
Outcome of the SAE(s) 
 
Medical records and laboratory/diagnostic information 
 
All paper forms and follow-up information submitted to Alexion GDS must be accompanied by a cover 
page signed by the Investigator.  
 
Paper source documents and/or reports should be kept in the appropriate section of the study file. 
 
 

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10.4. 
Appendix 4: Contraceptive Guidance and Collection of Pregnancy 
Information  
 
 
CONTRACEPTIVESa ALLOWED DURING THE STUDY INCLUDE: 
 
Highly Effective Methodsb That Have Low User Dependency  
 
Implantable progestogen-only hormone contraception associated with inhibition of ovulationc 
 
Intrauterine device (IUD): female participants with a Cu-containing IUD  
 
Intrauterine hormone-releasing system (IUS)c 
 
Bilateral tubal occlusion 
 
Vasectomized partner 
o 
(Vasectomized partner is a highly effective contraceptive method provided that the partner is the sole 
sexual partner of the woman of childbearing potential and the absence of sperm has been confirmed. If 
not, an additional highly effective method of contraception should be used. Spermatogenesis cycle is 
approximately 90 days.) 
 
Highly Effective Methodsb That Are User Dependent 
 
Progestogen-only hormone contraception associated with inhibition of ovulationc 
o 
Oral 
o 
Injectable 
 
Sexual abstinence 
o 
(Sexual abstinence is considered a highly effective method only if defined as refraining from 
heterosexual intercourse during the entire period of risk associated with the study intervention. The 
reliability of sexual abstinence needs to be evaluated in relation to the duration of the study and the 
preferred and usual lifestyle of the participant.) 
 
 
Female participants of non-childbearing potential are exempt from contraception requirements. Non-
childbearing potential for female patients is defined as any of the following: 
o Prior to first menses 
o Postmenopausal, as documented by amenorrhea for at least 1 year prior to the Day 1 visit and follicle 
stimulating hormone (FSH) serum levels consistent with postmenopausal status 
o Permanent sterilization at least 6 weeks prior to the Day 1 visit: 
 
Hysteroscopic sterilization 
 
Bilateral tubal ligation or bilateral salpingectomy 
 
Hysterectomy 
 
Bilateral oophorectomy 
a) Contraceptive use by men or women should be consistent with local regulations regarding the use of 
contraceptive methods for those participating in clinical studies. 
b) Failure rate of <1% per year when used consistently and correctly. Typical use failure rates differ from those 
when used consistently and correctly. 
c) If locally required, in accordance with Clinical Trial Facilitation Group (CTFG) guidelines, acceptable 
contraceptive methods are limited to those which inhibit ovulation as the primary mode of action. 
 
Note: Periodic abstinence (calendar, symptothermal, post-ovulation methods), withdrawal (coitus interruptus), 
spermicides only, and lactational amenorrhoea method (LAM) are not acceptable methods of contraception for 
this study. Male condom and female condom should not be used together (due to risk of failure with friction)

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Collection of pregnancy information 
o 
spouse/partner becomes pregnant during the 
Outcome Form" to Alexion Global Drug Safety (GDS) via fax or email (see Section 10.3 [Appendix 3] 
for contact information). When the outcome of the pregnancy becomes known, the form should be 
updated and submitted to Alexion GDS. If additional follow up is required, the Investigator will be 
requested to provide the information. 
o Exposure of an infant to an Alexion product during breastfeeding must also be reported (via the 
be reported to Alexion GDS or designee via email or facsimile (see Section 10.3 for contact 
information). 
 

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10.5. 
Appendix 5: Abbreviations 
A list of abbreviations and terms are used in this study protocol is provided in Table 8. 
Table 8: 
List of Abbreviations and Definitions of Terms 
Abbreviation 
Definition 
z 
apparent terminal-phase elimination rate constant  
AE 
adverse event  
ALT 
alanine aminotransferase  
ANOVA 
Analysis of Variance  
AST 
aspartate aminotransferase  
AUC 
area under the plasma concentration versus time curve 
AUCt 
AUC from time 0 to the last quantifiable concentration  
AUC  
AUC from zero to infinity  
BMI 
body mass index 
BUN 
blood urea nitrogen 
CYP 
cytochrome P450  
CYP2B6 
cytochrome P450 2B6 
CFR 
Code of Federal Regulations 
CI 
confidence interval 
CIOMS 
Council for International Organizations of Medical Sciences 
CL/F 
apparent oral clearance  
Cmax 
maximum observed plasma concentration  
CONSORT 
Consolidated Standards of Reporting Trials  
Cp 
ceruloplasmin 
CpC 
ceruloplasmin-bound copper 
CRF 
case report form  
CRU 
clinical research unit  
CTCAE 
Common Terminology Criteria for Adverse Events  
CTFG 
Clinical Trial Facilitation Group 
Cu 
copper  
CV 
coefficient of variation 
DDI 
Drug-Drug Interactions 
EC 
enteric-coated  
ECG 
electrocardiogram 
eCRF 
electronic case report form 
EMA 
European Medicines Agency 
EOS 
End of Study  
ET 
Early Termination 
EU 
European Union 
FDA 
Food and Drug Administration 

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GCP  
Good Clinical Practice  
GDS 
Global Drug Safety  
GMR 
geometric mean ratio 
HBsAg 
hepatitis B surface antigen 
HCV 
hepatitis C virus  
HIPAA 
Health Insurance Portability and Accountability Act  
HIV 
human immunodeficiency virus 
HLM 
human liver microsomes 
IB 
  
IC50 value 
drug concentration required to produce 50% of the maximal inhibition 
ICF 
informed consent form  
ICH 
International Council for Harmonisation 
IEC 
Independent Ethics Committee  
INR 
international normalized ratio 
IRB 
Institutional Review Board 
IUD 
intrauterine device 
IUS 
intrauterine hormone-releasing system 
LAM 
lactational amenorrhoea method 
LBC 
labile-bound copper 
Mo 
molybdenum  
MSE 
mean-square error 
MTD 
maximum tolerated dose 
NCC 
non-ceruloplasmin-bound copper  
NCCcorrected 
corrected NCC 
NCS 
not clinically significant 
PBC 
primary biliary cholangitis 
PD 
pharmacodynamics 
PI 
Principal Investigator 
PK 
pharmacokinetic(s)  
PMDA 
Pharmaceuticals and Medical Devices Agency 
PUF 
plasma ultrafiltrate  
QT 
interval between the start of the Q wave and the end of the T wave in an ECG  
QTcB 
la 
QTcF 
QT 
  
RBC 
red blood cell 
RNA 
ribonucleic acid 
SAE 
serious adverse event  
SAP 
Statistical Analysis Plan  
SoA 
Schedule of Activities 
SOC 
System Organ Class 

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SRC 
Safety Review Committee 
SUSAR 
suspected unexpected serious adverse reaction 
t½ 
terminal elimination half-life  
TDI 
time-dependent inhibition 
TEAE 
treatment-emergent adverse event 
TESAE 
treatment-emergent serious adverse event 
Tmax 
time to reach maximum observed plasma concentration  
TPC 
Tetrathiomolybdate-Cu-albumin tripartite complex formed after ALXN1840 
administration 
ULN 
upper limit of normal 
USPI 
United States Package Insert 
UWDRS 
Unified Wilson Disease Rating Scale  
Vd/F 
apparent volume of distribution  
WD 
Wilson Disease  
WHO 
World Health Organization 

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10.6. 
Appendix 6: Protocol Amendment History 
The protocol amendment summary of changes table for the current amendment is located 
directly before the Table of Contents. 
DOCUMENT HISTORY 
Document 
Type of 
Amendment 
(Global or 
Country-specific) 
Date 
Summary of Key Changes in the 
Amendment 
Amendment 1 
Not applicable 
16 Mar 2021 
Increased the number of participants 
randomized in the study from approximately 38 
to approximately 52. 
Original 
protocol 
Not applicable 
28 Apr 2020 
Not applicable 
 

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11. 
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Potential CYP2C8- and CYP2B6-Mediated Pharmacokinetic Interactions With Montelukast and 
Bupropion in Healthy Volunteers. Clin Pharmacol Drug Dev. 2018;7(8):860-870. 
Hedrich WD, Hassan HE, Wang H. Insights into CYP2B6-mediated drug-drug interactions. Acta 
Pharm Sin B. 2016;6(5):413-425. 
US Food and Drug Administration. Drug Development and Drug Interactions: Table of 
Substrates, Inhibitors and Inducers, Revised Dec 2019. 
Weiss K, Askari F, Czlonkowska A, et al. Bis-choline tetrathiomolybdate in patients with 
Wilson's disease: an open-label, multicentre, phase 2 study. Lancet Gastroenterol Hepatol. 
2017;12:869-876. 
WELLBUTRIN SR. WELLBUTRIN SR(bupropion hydrochloride) sustained-release tablets for 
oral use. GSK; Revised 2019.