Evidence - Evaluation of Potential Predictors of Disease Progression in Patients With aHUS, Including Genetics, Biomarkers and Treatment
Conditions: Atypical Hemolytic Uremic Syndrome
Sponsor: Alexion Pharmaceuticals, Inc.

Evaluation of Potential Predictors of Disease Progression in 
Patients with aHUS, Including Genetics, Biomarkers, and 
Treatment (EVIDENCE) 
 
 
Unique Protocol ID: 
ECU-aHUS-403 
NCT Number: 
NCT02614898 
EudraCT Number:  
2015-003135-35 
Date of Protocol/SAP:  
05 August 2015 
 

Protocol ECU-aHUS-403 Amendment 2 
 
Alexion Pharmaceuticals, Inc. 
 
 
17 November 2016 
1. 
TITLE PAGE 
PROTOCOL NUMBER: ECU-aHUS-403 
EVIDENCE 
EVALUATION OF POTENTIAL PREDICTORS OF DISEASE PROGRESSION IN 
PATIENTS WITH aHUS, INCLUDING GENETICS, BIOMARKERS, AND 
TREATMENT 
IND #011075 
EUDRACT NUMBER: 2015-003135-35 
Sponsor: 
Alexion Pharmaceuticals Inc.  
100 College St, New Haven, CT 06510 USA 
 
Sponsor Contact: 
 
 
Alexion Pharmaceuticals, Inc.  
100 College St, New Haven CT 06510 USA 
Telephone: 
 
Fax:
Email: 
 
 
Medical Monitor: 
 
 
100 College St, New Haven, CT 06510 USA 
Telephone: 
 
Fax: 
 
Email: 
 
 
 
Original Date of Protocol: 
Amendment 1 Date of Protocol: 
Amendment 1.1 (UK-specific) Date of Protocol:   
Amendment 2 Date of Protocol: 
05 August 2015 
29 December 2015 
05 August 2016 
17 November 2016 
This protocol contains confidential information and is provided for exclusive use of 
Investigators. This information may only be disclosed to those persons involved in this study 
who have a need to know with the obligation not to further disseminate this information. This 
information may not be disclosed to other individuals unless such disclosure is required by 
federal or state law or regulations subject to the foregoing. These restrictions on disclosure will 
apply equally to all future oral or written information supplied to you by Alexion which is 
designated as “privileged” or “confidential.” 
 
 
 
 
 
 
 
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Protocol ECU-aHUS-403 Amendment 2 
 
Alexion Pharmaceuticals, Inc. 
 
 
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INVESTIGATOR’S AGREEMENT 
 
 
 
I have read the ECU-aHUS-403 study protocol Amendment 2 and agree to conduct the study as 
outlined.  I agree to conduct the trial in accordance with ethical principles that have their origin 
in the Declaration of Helsinki and are consistent with International Council on Harmonisation 
(ICH)/Good Clinical Practice (GCP) and applicable regulatory requirements.  I also agree to 
maintain the confidentiality of all information received or developed in connection with this 
protocol. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Printed Name of Investigator 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Signature of Investigator 
 
 
 
 
 
 
 
 
Date: 
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PROCEDURES IN CASE OF EMERGENCY 
 
Table 1: 
Emergency Contact Information 
 
Role in Study 
Name 
Address and Telephone number 
Clinical Study Leader 
 
 
Alexion Pharma Spain 
Passeig de Gracia 85, 08008 Barcelona 
Mobile: 
 
Fax:  
 
Email: 
 
Clinical Study Leader 
 
 
Alexion Pharmaceuticals, Inc.  
100 College St 
New Haven CT USA 06510 
Tel: 
 
Fax
Email: 
 
Medical Monitor 
 
Alexion Pharmaceuticals, Inc.  
100 College St 
New Haven CT USA 06510 
Tel: 
 
Fax:
Email: 
 
Drug Safety 
Representative 
 
Alexion Europe SAS  
1-15, avenue Edouard Belin 
92500 Rueil-Malmaison 
Tel: 
 
Email:
 
Serious Adverse Event 
Reporting 
Alexion Pharmaceuticals, Inc. 
Alexion Pharmaceuticals, Inc. 
100 College St 
New Haven, CT. 06510 
Email: 
  
Fax: 
 
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Protocol ECU-aHUS-403 Amendment 2 
 
Alexion Pharmaceuticals, Inc. 
 
 
17 November 2016 
2. 
SYNOPSIS 
Name of Sponsor/Company: Alexion Pharmaceuticals, Inc. 
 
Name of Investigational Product: All treatment decisions will be left to the Treating Physician’s 
discretion and therefore no investigational product will be supplied during the study. 
 
Title of Study: EVIDENCE – EValuation of Potential PredIctors of Disease ProgrEssion in 
Patients with aHUS, Including GeNetiCs, BiomarkErs, and Treatment. 
 
Study center(s): No limit 
Principal Investigator:   
Investigators: A list containing all Investigators will be provided when site selection is 
completed. 
Studied period (years): Up to a maximum of 4 years 
Estimated date first patient enrolled: Q4 2015 
Estimated date last patient enrolled: Q4 2017 
Phase of development: Phase IV 
 
Study Rationale:  
Atypical hemolytic uremic syndrome (aHUS) is a rare, progressive, and life-threatening 
disease that affects both children and adults (Zimmerhackl, 2006). Atypical hemolytic uremic 
syndrome is a disease of complement dysregulation, frequently resulting from mutations in 
complement and/or coagulation pathway genes or from autoantibodies against complement 
proteins.  Specific genetic complement mutations or antibodies are only currently identifiable 
in approximately 50% to 70% of patients diagnosed with aHUS (Noris, 2010; Matis, 1995).  
Chronic uncontrolled terminal complement activation causes complement-mediated 
thrombotic microangiopathy (TMA), a pro-thrombotic and pro-inflammatory state (Matis, 
1995; Karpman, 2006), characterized by endothelial cell activation, the release of von 
Willebrand factor, platelet activation and aggregation, leukocyte recruitment and a pro-
coagulant state (Ballermann, 1998).  The prognosis in aHUS is poor with more than half of all 
patients dying, requiring dialysis, or having permanent kidney damage within 1 year of 
diagnosis (Caprioli, 2006).   
Eculizumab is a high affinity humanized monoclonal antibody (mAb) that binds to and blocks 
the cleavage of C5 into the inflammatory, pro-thrombotic end molecule C5a and lytic 
membrane attack complex, C5b-9, leaving the upstream components of complement, most 
notably C3b, intact.  Uncontrolled complement activation observed in aHUS patients coupled 
with the established activity of eculizumab to selectively inhibit terminal complement 
activation provided a mechanistic rationale for the evaluation of eculizumab in the treatment 
of aHUS.  Eculizumab is approved for the treatment of aHUS in 39 countries, including the 
European Union and the USA in 2011, and Australia in 2012.   
There is growing but limited information on the long term clinical status of aHUS patients 
who have previously received or are continuing to receive treatment with eculizumab. An 
observational registry study (M11-001 aHUS Registry) designed to collect clinical data to 
provide insight into the long-term outcomes of patients with aHUS and fulfill post-marketing 
commitments is ongoing. This study (ECU-aHUS-403) aims to provide greater insight into 
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risk factors for manifestations of TMA in patients with aHUS disease into risk of disease 
progression in relationship to standard of care treatment (defined as eculizumab approved 
treatment). 
Several recent consensus papers regarding aHUS treatment clearly mention eculizumab as a 
part of the standard of care, and recommend its use as first-line treatment in many situations 
(Zuber, 2012; Campistol, 2013; Loirat, 2016; Nester, 2015). In order to provide further 
guidance on the chronicity of treatment in patients with aHUS, this study aims to assess TMA 
manifestations in relationship to treatment.  This study will also seek to identify predictors of 
TMA manifestations, including genetic profile, and to further elucidate mechanisms of disease 
and response to treatment through biomarker assessment.  Finally, long-term effects on kidney 
function in relationship to treatment and other factors will also be assessed. 
This is a real-world study and as such, all treatment decisions will be left to the Treating 
Physician’s discretion. 
Study Objectives:  
The main purpose of this study is to assess TMA disease manifestations in patients with aHUS 
with or without ongoing eculizumab treatment in a real-world setting.  
Additional objectives of this study are to evaluate potential clinical predictors of disease 
manifestation and progression, including clinical characteristics and genetic profiling to 
evaluate disease activity and relationship to treatment as determined by levels of biomarkers 
associated with complement activation, and the use of associated supportive interventions such 
as plasma exchange/plasma infusion (PE/PI), dialysis, blood transfusions, and renal 
transplantation.   
 
Study Design and Methodology:  
Study (ECU-aHUS-403) is a prospective, non-randomized, open-label cohort study of patients 
with aHUS enrolled in the M11-001 aHUS Registry and currently receiving eculizumab with 
no prior intentional eculizumab discontinuations at any time (ie, not occasional, unplanned, or 
temporary missed doses of eculizumab, but intended long-term discontinuation).  
The study will assess disease manifestation in patients receiving ongoing eculizumab 
treatment compared to those who intentionally discontinue eculizumab treatment.  This is an 
open-label study with no randomization performed for patients.  Treatment for aHUS will 
remain observational and at the discretion of the Treating Physician.   
Approximately, 330 eligible patients, not to exceed 340 patients, enrolled in the M11-001 
aHUS Registry are expected to participate in this study.  Patients will enroll via competitive 
enrollment (ie, as patients become available at the site).  Treatment is provided at the Treating 
Physician’s discretion, therefore intentional discontinuation of eculizumab and re-initiation of 
eculizumab may occur during the study.  At the Treating Physician’s discretion, some patients 
may receive a reduced/increased eculizumab dosing regimen (ie, reduced/increased dose and 
or reduced/increased frequency of eculizumab).   
Patients receiving ongoing eculizumab treatment (whether dosed as recommended in product 
labeling or on a reduced/increased dosing regimen) without any intentional eculizumab 
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discontinuation will have assessments every 2 weeks (Q2W) through Week 10 and monthly 
assessments thereafter beginning at Month 3 to Month 24, a period of 2 years, at which time 
they will complete the study.   
Patients intentionally discontinued from eculizumab treatment before reaching Month 24 of 
eculizumab treatment, will commence a new schedule of assessments, immediately following 
the intentional discontinuation through 2 years from the time of their first intentional 
eculizumab discontinuation at which time they will complete the study.   
The 2 year-assessment period will commence within 2 weeks after the last eculizumab 
infusion and this 2 year-assessment period following intentional discontinuation will not 
change if eculizumab treatment is re-initiated, ie, patients who re-initiate eculizumab after an 
intentional discontinuation will complete the study 2 years from the time of their first 
intentional eculizumab discontinuation.  Consequently, the maximum possible time on the 
study for any patient is approximately 47 months, comprising 23 months of continuous 
eculizumab treatment, followed by an intentional discontinuation and another 24 months of 
study assessments, which may include periods of eculizumab re-initiation and subsequent 
intentional discontinuation of eculizumab treatment.   
Prior to initiating any study procedure, the informed consent form (ICF) will be signed by the 
patient or patient’s guardian and inclusion/exclusion criteria will be obtained and evaluated.  
At Day 0 (Baseline)/Visit 1, the patient will be assessed for study eligibility through medical 
history review, demographic data, and safety assessments (vital signs, physical examination, 
laboratory tests, assessments of TMA manifestations, eculizumab treatment status, and 
associated supportive interventions, adverse events [AEs], concomitant medications/therapies).  
Patient-reported outcomes (PRO) using Functional Assessment of Chronic Illness Therapy 
(FACIT)-Fatigue instrument, European Organization for Research and Treatment of Cancer 
quality of life questionnaire (EORTC QLQ-C30), and specific patient-reported aHUS 
symptoms will be assessed. 
On Day 0 (Baseline)/Visit 1, safety assessments will be performed prior to blood or urine 
sample collection for biomarker tests.  Blood samples for cRBC hemolytic assay, free C5, and 
pharmacokinetics (PK) will be collected.  Samples for genetic testing will be collected from 
patients during the study at this visit or any other visit thereafter.  A patient may be allowed to 
opt-out from providing a sample for genetic testing (eg, for religious reasons) and still 
participate in the study.  Blood and urine for laboratory tests should be collected 5 to 
90 minutes prior to administration of eculizumab.  If the scheduled eculizumab dose falls 
within a study visit window, the study visit should be scheduled on the same day of the dose or 
within 48 hours prior to the dose, such that laboratory samples can be taken prior to the 
eculizumab dose. If the scheduled dose falls on the same day as the scheduled visit, blood 
samples are to be taken 5 to 90 minutes prior to administration.  It is preferred that the dose is 
scheduled on the same day as the visit, if possible.  Patient-reported outcomes using FACIT-
Fatigue instrument, EORTC QLQ-C30, and specific patient-reported aHUS symptoms will be 
assessed. 
Study Year 1 and 2 - Patients Receiving Ongoing Eculizumab Treatment 
After completing the Day 0 (Baseline), patients will return to the site for Q2W study visits 
from Week 2 through Week 10, followed by monthly study visits until the end of the study. 
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Patients receiving ongoing eculizumab treatment will have monthly study visits beginning at 
Month 3 through Month 24.  If a patient completes all the study visits, then the end-of-study 
(EOS) visit will be scheduled at which time the patient completes the study.  Safety 
assessments will be performed at every visit prior to collection of samples for biomarker 
analyses and administration of eculizumab.  Blood and urine samples for biomarkers will be 
collected at every visit.  Samples for genetic testing will be collected from patients on Day 0 
(Baseline) however, may alternatively be collected at any other visit during the study after 
Day 0 (Baseline).  Patient-reported outcomes using FACIT-Fatigue instrument, EORTC 
QLQ-C30, and specific patient-reported aHUS symptoms will be assessed at pre-specified 
visits.   
For patients receiving eculizumab, blood samples for free C5, PK, and cRBC hemolytic assay 
will be collected every 6 months beginning at Month 6 through Month 24.  For patients 
receiving eculizumab at a reduced/increased eculizumab dosing regimen, blood samples for 
free C5, PK, and cRBC hemolytic assay will be collected at the time of dose reduction and 
monthly thereafter as long as the patient continues to be on that reduced/increased eculizumab 
dosing regimen.   
If a patient enters the study on a reduced/increased eculizumab dosing regimen, blood samples 
for PK and cRBC hemolytic assay will be collected monthly as long as the patient remains on 
a reduced/increased eculizumab dosing regimen. 
If a patient experiences a TMA manifestation, assessments and sample collection as specified 
in the TMA manifestation visit will be performed.  Additional blood samples may be collected 
as needed, at scheduled or unscheduled visits at the discretion of the Investigator or the 
treating physician.   
Study Year 1 and 2 – Patients Who Discontinue Eculizumab 
First Intentional Eculizumab Discontinuation: 
 
Following the first intentional eculizumab discontinuation, patients will have a study visit 
within 2 weeks (±2 days) after the last eculizumab infusion, followed by Q2W study visits 
from Week 2 through Week 10.  Beginning at Month 3, patients will have monthly study visits 
for a total of 2 years.  If a patient completes all the study visits, then an EOS visit will be 
scheduled, at which time the patient completes the study. 
Safety assessments will be performed at every visit prior to collection of samples for 
biomarker analyses.  Blood and urine samples for biomarkers will be collected at every visit.  
Blood samples for cRBC hemolytic assay, PK, and free C5 will be collected at pre specified 
time points.  Patient-reported outcomes using FACIT-Fatigue instrument, EORTC QLQ-C30, 
and specific patient-reported aHUS symptoms will be assessed at pre-specified visits. 
Subsequent Intentional Eculizumab Discontinuation(s):  
For any subsequent intentional eculizumab discontinuation, patients will follow the same 
assessments as with the first intentional eculizumab discontinuation visit followed by Q2W 
study visits thereafter from Week 2 through Week 10.  Patients will have monthly visits 
beginning at Month 3 after intentional eculizumab discontinuation for a total of 2 years from 
the time of their first intentional eculizumab discontinuation.  The monthly visits will follow 
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the schedule as determined by the date of the first intentional eculizumab discontinuation.   
Study Year 1 and 2 – Patients Who Re-initiate Eculizumab  
Re-initiation After the First Intentional Eculizumab Discontinuation: 
Patients who re-initiate eculizumab will have a study visit within 1 week prior to re-initiation 
of eculizumab.  At this visit, safety assessments will be performed prior to collecting blood 
and urine samples for biomarker tests.  Blood samples will be collected for cRBC hemolytic 
assay, free C5, and PK.   
Following the visit just prior to re-initiation of eculizumab, patients will have Q2W study 
visits from Week 2 through Week 10.  Patients will have monthly study visits beginning at 
Month 3 through up to 2 years after the time of their first intentional eculizumab 
discontinuation.  These monthly visits will follow the schedule as determined by the date of 
the first intentional eculizumab discontinuation.  At these monthly visits, safety assessments 
will be performed prior to collection of samples for biomarker analyses.  Blood samples for 
cRBC hemolytic assay, free C5, and PK will be collected at pre-specified time points. 
Re-initiation After the Subsequent Intentional Eculizumab Discontinuation(s): 
For any subsequent eculizumab re-initiation, patients will have a re-initiation study visit within 
1 week prior to re-initiation of eculizumab and follow the same assessments as with the 
re-initiation after their first intentional eculizumab discontinuation.  Patients will have Q2W 
study visits from Week 2 through Week 10, followed by monthly study visits thereafter for a 
total of 2 years from the time of the first intentional eculizumab discontinuation.  These 
monthly visits will follow the original schedule as determined by the data of first intentional 
eculizumab discontinuation.   
Assessments for TMA Manifestations: 
The TMA manifestation visit should be performed as soon as possible on recognition of signs 
and/or symptoms of TMA manifestation onset by the Investigator.  Changes in specific 
laboratory parameters (platelet count, serum creatinine, serum lactate dehydrogenase [LDH], 
and haptoglobin) along with renal and extra-renal signs and symptoms will be assessed at 
these visits, and can be derived from local and/or central laboratories.  Data will be collected 
regardless of relationship to TMA in the opinion of the Investigator. 
If a patient experiences a TMA manifestation, 2 TMA manifestation visits will be performed; 
the 1st TMA visit will be conducted as described above, as soon as possible on recognition of 
signs and symptoms of TMA manifestation onset by the Investigator and the 2nd TMA visit 
will be performed within 2 weeks of the first TMA visit. 
Scheduled visits, when overlapping with other visits (eg, TMA visit, re-initiation visits), can 
be combined as appropriate. 
Assessments of Eculizumab Treatment and Supportive Interventions: 
For assessment of eculizumab treatment, the following information will be collected at every 
visit in the eculizumab treatment log: 
• eculizumab dose administered  
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• eculizumab dosing frequency 
• any changes in eculizumab dosing regimen (dose and/or frequency) 
− reason for change in dosing regimen  
• whether eculizumab was discontinued 
− reason for intentional eculizumab treatment discontinuation  
• whether eculizumab was re-initiated 
− reason for re-initiation 
For the assessment of associated supportive interventions, the use of treatments such as PE/PI, 
dialysis, blood transfusions, and renal transplantation will be collected at every visit during the 
study. 
Study Endpoints:  
Primary endpoint: 
Rate of TMA manifestations, where TMA includes: 
1. Hematologic or renal events due to aHUS 
2. Extra-renal clinical signs and symptoms of aHUS 
3. Tissue (eg, kidney transplant) biopsy demonstrating TMA due to aHUS  
Secondary endpoints: 
• Change in estimated Glomerular Filtration Rate (eGFR) over time using the 
chronic kidney disease-epidemiology (CKD-EPI) formula 
• Rate of TMA manifestations  
− while patient is on a labeled eculizumab dosing regimen 
− while patient is on a reduced/increased eculizumab dosing regimen 
(reduced/increased dose and or reduced/increased frequency) 
• Incidence of PE/PI  
Exploratory endpoints: 
• Changes in exploratory biomarker levels: 
− Biomarkers may include, but are not limited to: Ba, TNFR1, sVCAM-1, TM, 
D-dimer, markers of renal injury (eg, Cystatin C or other) and assessments of 
complement deposition on endothelial cells 
• Changes in PK (serum eculizumab concentration), pharmacodynamic (PD) (ie, 
cRBC hemolytic assay), and free C5 
• Identification of novel genetic variants associated with aHUS  
• Development of progressive proteinuria 
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• Incidence of change in dosing of eculizumab: 
− Re-initiation of eculizumab after discontinuation 
− Start of labeled dosing after reduced/increased dosing 
• Incidence of transfusion 
• Patient-reported outcomes (FACIT-Fatigue [Appendix 2 and Appendix 3], EORTC 
QLQ-C30 [Appendix 4], and patient-reported aHUS symptoms [Appendix 5]) 
Criteria for Site Reporting of Potential TMA Manifestations 
Data on all hematologic, renal, extra-renal clinical signs and symptoms, and tissue biopsy 
results will be collected whether the physician deems related or not to aHUS.  Information on 
etiology will be collected on clinical signs and symptoms deemed not related to aHUS will 
also be collected.  Only criteria considered related to aHUS will be reported as a potential 
TMA manifestation under the primary endpoint. 
For the purposes of reporting, a potential TMA manifestation is defined by at least one of the 
following criteria, although multiple criteria may be identified: 
1. Hematologic or renal events due to aHUS 
A. The occurrence of two or more of the following 3 hematologic or renal events, 
where the changes from baseline* (see baseline definition below) in laboratory 
values are confirmed by a 2nd consecutive value derived from local and/or central 
laboratories; if local laboratory values are to be used, they must be reported to the 
sponsor): 
• A decrease in platelet count by ≥25% below baseline and below the lower limit of 
normal (LLN) 
• Evidence of hemolysis, defined by at least one of the following: 
− An increase in serum LDH by ≥25% above baseline and above the upper limit 
of normal (ULN) 
− A decrease in haptoglobin below the LLN 
• A decline in kidney function that includes at least one of the following: 
− An increase in serum creatinine by ≥25% above baseline and above the ULN 
− An increase in proteinuria characterized by at least one of the following:  
- 
New onset of proteinuria: ≥2+ on urine dipstick or spot urine albumin to 
creatinine ratio ≥0.3 mg albumin/mg creatinine;  
- 
Worsening of existing proteinuria: ≥1.5 x increase in spot urine protein-to-
creatinine ratio from baseline 
- 
New onset of nephrotic-range proteinuria: spot urine protein-to-creatinine 
ratio from baseline of >3.5 mg protein/mg creatinine in adults and >3.0 mg 
protein/mg creatinine in children  
− Requirement for renal replacement therapy, including dialysis or kidney 
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transplant 
B. The occurrence of two or more of the following 3 hematologic or renal events, that 
do not necessarily meet all the criteria listed under #1A above, but are due to aHUS 
in the opinion of the Investigator: 
• A clinically important decrease in platelet count 
• Evidence of hemolysis, defined by at least one of the following: 
− A clinically important increase in serum LDH  
− A decrease in haptoglobin below the LLN 
• A clinically important decline in kidney function that includes at least one of the 
following: 
− A clinically important increase in serum creatinine  
− A clinically important increase in proteinuria, for example: new onset 
proteinuria, worsening of existing proteinuria, or new onset of nephrotic range-
proteinuria 
− Requirement for renal replacement therapy, including dialysis or kidney 
transplant related to a TMA event 
*For reporting purposes, baseline is defined as follows:   
For a patient on ongoing eculizumab treatment without any treatment discontinuation, the 
baseline is the value at Day 0.  For a patient re-initiated on eculizumab treatment with at least 
one prior intentional discontinuation, the baseline for each on treatment period is the last 
laboratory value during the preceding intentional discontinuation period.  For a patient 
intentionally discontinued from eculizumab treatment, the baseline for each off treatment 
period is the last value during the preceding ongoing eculizumab treatment period. 
2. Extra-renal clinical signs and symptoms of aHUS 
The occurrence of extra-renal clinical signs and symptoms that in the opinion of the 
Investigator are due to aHUS AND at least one other test result that is consistent with the 
diagnosis of TMA related to aHUS OR excludes alternative etiologies of extra-renal signs 
and symptoms: 
• A single occurrence of any component of criterion #1A or #1B (hematologic or 
renal events due to aHUS) defined above (second/confirmatory value for 
laboratories not required) 
AND/OR 
• Relevant imaging study/studies demonstrating either tissue damage or excluding 
etiologies other than aHUS (eg, abdominal ultrasound that shows no gallstone in a 
setting of pancreatitis) 
AND/OR 
• Relevant laboratory data ruling out etiologies other than aHUS (eg, negative 
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hepatitis serologies)  
3. Tissue biopsy demonstrating TMA due to aHUS 
Adjudication of Potential TMA Manifestations 
Events reported as meeting criteria (#1A, #1B, 2, or 3) listed above as well as potential events 
not indicated as meeting criteria will be adjudicated by an independent Endpoint Adjudication 
Committee as detailed in the Adjudication Committee Charter. 
Diagnosis and main criteria for inclusion:  
Inclusion Criteria: 
Patients of any age, including minors, enrolled in the M11-001 aHUS Registry should meet all 
of the inclusion criteria below to be eligible for enrollment in the study: 
1. Currently receiving eculizumab treatment in the M11-001 aHUS Registry  
2. Two normal platelet counts (eg, >150,000/μL) at least 4 weeks apart while on 
eculizumab within the past 12 months 
3. Two normal LDH levels (eg, <1.5 x ULN) at least 4 weeks apart while on eculizumab 
within the past 12 months 
4. Willing, committed, and able to return for ALL clinic visits and complete all study-         
related procedures  
5. Patient or patient’s parent/legal guardian must be willing and able to give written 
informed consent.  Patient (if minor) must be willing to give written informed assent (if 
applicable as determined by the central Institutional Review Boards/Independent Ethics 
Committees [IRB/IEC]). 
Exclusion Criteria: 
Patients enrolled in the M11-001 aHUS Registry Study who meet any 1 of the following 
criteria will be excluded from the study:  
1. Any prior intentional discontinuation of eculizumab treatment  
2. On chronic dialysis (defined as ≥3 months on dialysis) 
3. Currently participating in another complement inhibitor trial 
4. With life expectancy of <6 months 
5. Patient or patient's parent/legal guardian unable to give written informed consent.  
Patient (if minor) unable to give written informed assent (if applicable as determined 
by the central Institutional Review Boards/Independent Ethics Committees [IRB/IEC]). 
Duration of treatment:   
Treatment is provided at the Treating Physician’s discretion, therefore discontinuation of 
eculizumab and re-initiation of eculizumab may occur during the study.  At the Treating 
Physician’s discretion, some patients may receive a reduced/increased eculizumab dosing 
regimen (ie, reduced/increased dose and/or reduced/increased frequency of eculizumab). 
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Statistical Analysis:  
This study (ECU-aHUS-403) aims to assess TMA manifestations in patients with aHUS with 
or without ongoing eculizumab treatment.  Treatment for aHUS is non-randomized and is at 
the discretion of the Treating Physician.  Hypothesis testing will be done using a two-sided 
α=0.05 Type 1 error rate, unless otherwise stated.  For continuous variables, descriptive 
statistics (number of patients with non-missing values [N], mean, standard deviation [SD], 
median, minimum, and maximum) will be provided.  For categorical variables, patient counts 
and percentages will be presented.  The percentages will be calculated based on the total 
number of patients in the full analysis set (FAS) or the safety set.   
Eculizumab Treatment Status: 
All patients at their entry into the study will be receiving eculizumab treatment, dosed either 
on-label or at a reduced/increased dosing regimen, with no prior intentional discontinuation(s) 
of eculizumab treatment.  Once enrolled in the study, patients are allowed to discontinue 
eculizumab treatment or re-initiate eculizumab treatment at the discretion of the Treating 
Physician. 
Eculizumab treatment status will be classified for analytical purposes as follows: 
• 
On eculizumab treatment: from the date of enrollment through three weeks after last 
infusion of eculizumab or until the patient withdraws from the study, or until the patient 
completes the study, whichever occurs first.   
• 
Off eculizumab treatment: from three weeks after the last infusion of eculizumab and 
continue until the patient re-initiates eculizumab treatment or until the patient withdraws from 
the study, or until the patient completes the study, whichever occurs first.  
For both the above categories, the time will accrue as specified until the patient changes 
treatment status category, or until the patient is withdrawn from the study, or until the patient 
completes the study. 
Primary Endpoint Analyses: 
Primary analyses will focus on comparison of rates (ie, adjusted appropriately for exposure 
periods) of new TMA disease manifestations between time on eculizumab treatment and time 
off eculizumab treatment.   
In this context in which treatment exposure is a time varying confounder in that it affects the 
occurrence of a TMA disease manifestation and can subsequently be affected by a TMA 
disease manifestation, marginal structural models will be used.  Marginal structural models 
estimation employs inverse-probability of treatment weighting (IPTW) and robust estimation 
methods.  The goal of IPTW estimation is to obtain coefficients to create weights that will 
redistribute the population so that, in this case, treatment exposure is not temporally 
confounded (ie, creating a pseudo-population in which treatment exposure is no longer 
temporally confounded).  The factors that may confound the association are considered in a 
treatment model (or weight model), which is used as part of the IPTW estimation methodology 
to obtain estimates of, again in this context, difference in incidence rates between time on and 
off treatment. 
 
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Differences between incidence rates of TMA disease manifestations will be estimated using 
negative binomial regression.   
Secondary Endpoint Analyses: 
Secondary endpoints include change over time for eGFR.  Change over time will be 
summarized using repeated measures models starting from baseline.  Mean changes from 
baseline will be analyzed using a restricted maximum likelihood based repeated measure 
approach.  Summary statistics will be presented at baseline and follow-up time points and 
mean change from baseline will be estimated by eculizumab treatment status. 
The primary analyses will be repeated with a distinction for the time on eculizumab treatment 
as on-label or as on reduced/increased dosing regimen.  The focus will be on comparison of 
rates (ie, adjusted appropriately for exposure periods) of new TMA disease manifestations 
between:  
• time off eculizumab treatment and time on on-label eculizumab treatment, and  
• time on off-label eculizumab treatment and time on on-label eculizumab treatment 
The number of occurrences of PE/PI per patient-years will be calculated and summarized by 
treatment status. 
Safety Analyses: 
AEs and general medical/surgical histories will be coded by primary system organ class (SOC) 
and preferred term using the Medical Dictionary for Regulatory Activities (MedDRA) 
(Version 13.0 or the most current).  All events from time of enrollment in the study will be 
included in the analyses.  The number and percentage of patients with AEs will be summarized 
by preferred terms, SOC, severity (mild, moderate, severe), relationship to eculizumab 
treatment, and treatment status.  If a patient has more than one occurrence of an AE, the most 
severe occurrence of the AE will be used in the severity summary table, and the strongest 
relationship to eculizumab treatment will be used in the relationship to eculizumab treatment 
table. 
Similarly, the number and percentage of patients with SAEs will be summarized by preferred 
terms, SOC, severity (mild, moderate, severe), relationship to eculizumab treatment, and 
treatment status. 
To account for differences in time spent on and off treatment, the number of AEs and SAEs 
per patient years will be calculated and summarized. 
The number and percentage of patients with AEs resulting in death, study withdrawal, and 
intentional eculizumab treatment discontinuation will be summarized. 
Physical Examinations and Vital Signs 
Physical examinations will be collected at baseline for all patients and will be summarized.  
Vital signs (systolic and diastolic BP, temperature, and sitting or lying HR), height (only for 
pediatric patients and baseline only for adults), and weight and changes from baseline in vital 
signs (including height and weight) will be summarized by visit.  Listings of physical 
examinations and vital signs will be produced. 
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Laboratory Assessments 
Changes from baseline in laboratory assessments (chemistry and hematology,) will be 
summarized by visit. Likewise, shift tables (L [low], N [normal], H [high]) by visit and 
treatment status will be produced for clinical laboratory tests.  Listings of laboratory data will 
be produced.  
Exploratory Endpoint Analyses 
Pharmacokinetic/Pharmacodynamic/Biomarker Analyses 
Pharmacokinetic, PD, and biomarker analyses will be performed on all patients who have 
evaluable PK, PD, and biomarker data, respectively.   
Graphs of plasma eculizumab concentration time profiles for individual patients and for means 
will be provided.  Plasma eculizumab concentrations by collection day and time will be 
summarized by tabulations of mean, SD, median, minimum and maximum. Population PK 
analysis and PK-PD analyses will be conducted using eculizumab plasma concentrations, 
hemolytic activity and free C5 data, and selected biomarker data. PK and PK-PD model 
parameters and the variability will be estimated, and the potential covariates, such as 
demographics, disease severity, genetic markers, will be assessed.  Graphic exploration of 
exposure versus the selected efficacy or safety endpoints will be made, and subsequent 
exposure response analyses may be performed if graphic exploration suggests that a 
relationship exists.   
For PD and exploratory biomarker assessments, summary tabulations of mean, SD, median, 
minimum and maximum will be presented.  The relationship between changes in PD 
biomarkers, exploratory biomarkers, and the effects of eculizumab treatment, as well as the 
effects of treatment discontinuation, will be evaluated.   
For the exploratory biomarker analyses, the relationship between eculizumab concentration 
and the key and exploratory biomarkers or the correlation between clinical benefit and key 
exploratory biomarkers will be assessed by graphical display.  Potential relationships between 
clinical outcomes, PK/PD, genetic profile and biomarker levels will be explored.  Additional 
model-based exploratory analyses may be performed. 
Repeated measures model analyses similar to the ones performed for the change in eGFR will 
be conducted for biomarkers (Ba, TNFR1, sVCAM-1, TM, D-dimer, markers of renal injury 
(eg, Cystatin C)) to be measured in the study. Summary statistics will be presented at baseline 
and follow-up time points and mean change from baseline will be estimated.  The number of 
occurrences per patient-years of (1) re-initiation of eculizumab treatment after discontinuation, 
(2) change from reduced/increased to labeled dosing, and (3) blood transfusion, will be 
calculated and summarized.  Summary statistics for proteinuria levels, FACIT-fatigue scores 
observed values and changes from baseline over time, and EORTC QLQ-C30 scale before and 
after discontinuation will be provided. Summary statistics (proportions) for patient reported 
aHUS symptoms, including severity, frequency, and impact will be reported before and after 
discontinuation. 
Genetic Analyses 
Genetic testing will include analysis of variants in genes known to be associated with aHUS.  
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Additional exploratory genetic analyses may be performed to identify novel genetic variants 
associated with aHUS or disease modifying genes.  Such variants may be validated by a 
second sequencing method and validated variants will be summarized across the study 
population.  Potential relationships between clinical outcomes, treatment status, biomarkers, 
and genetic variants will be explored.   
Sample Size Rationale:  
The primary outcome of the study is TMA manifestation as a dichotomous variable.  
Preliminary data from the aHUS Registry shows about 20% of patients reporting 
discontinuation of eculizumab treatment.  Additionally, longitudinal data on file at Alexion 
shows a difference of 15% in proportion of patients with TMA manifestations between 
patients who discontinue treatment compared to those who remain on treatment.  The 
estimated sample size needed to detect a difference of 15% in TMA manifestations with 
power=80% in the proposed study is 300 patients (60 patients with eculizumab treatment 
discontinuation and 240 patients who continue ongoing treatment).  Assuming a 10% loss to 
follow-up, the estimated sample size needed for the study is 330 patients. 
 
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3. 
TABLE OF CONTENTS, LIST OF TABLES, AND LIST OF 
FIGURES  
TABLE OF CONTENTS 
1. 
TITLE PAGE ................................................................................................................1 
2. 
SYNOPSIS ...................................................................................................................5 
3. 
TABLE OF CONTENTS, LIST OF TABLES, AND LIST OF FIGURES ...............18 
4. 
LIST OF ABBREVIATIONS AND DEFINITIONS OF TERMS.............................24 
5. 
INTRODUCTION ......................................................................................................26 
5.1. 
Overview of Atypical Hemolytic Syndrome Disease .................................................26 
5.2. 
Rationale for the Study Design ...................................................................................26 
5.3. 
Rationale for Genetic and Biomarker Testing ............................................................27 
6. 
STUDY OBJECTIVES AND PURPOSE ..................................................................28 
7. 
INVESTIGATIONAL PLAN .....................................................................................29 
7.1. 
Overall Study Design and Plan Description ...............................................................29 
7.1.1. 
Study Year 1 and 2 - Patients Receiving Ongoing Eculizumab Treatment ................31 
7.1.2. 
Study Year 1 and 2 – Patients Who Discontinue Eculizumab....................................32 
7.1.3. 
Study Year 1 and 2 –Patients Who Re-initiate Eculizumab .......................................33 
7.2. 
Schedule of Assessments ............................................................................................34 
7.3. 
Study Endpoints ..........................................................................................................45 
7.3.1. 
Primary endpoint: .......................................................................................................45 
7.3.2. 
Secondary endpoints: ..................................................................................................45 
7.3.3. 
Exploratory endpoints: ................................................................................................45 
7.3.4. 
Safety endpoints: ........................................................................................................45 
7.3.5. 
Criteria for Site Reporting of Potential TMA Manifestations ....................................46 
7.3.6. 
Adjudication of Potential TMA Manifestations .........................................................47 
7.4. 
Study Visit Procedures ...............................................................................................48 
7.4.1. 
Core Procedures Performed At All Regularly Scheduled Study Visits and the 
1st TMA Visits ............................................................................................................48 
7.4.2. 
Visits for TMA Manifestation for all patients regardless of eculizumab 
treatment status: Visit 1T/1TD/1TR and Visit 2T/2TD/2TR .....................................49 
7.4.2.1. 
First (1st) TMA Visit - Upon Recognition of TMA Manifestation .............................49 
7.4.2.2. 
Second (2nd) TMA Visit - Within 2 weeks [±2 days] of the 1st TMA Visit ...............50 
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7.4.3. 
Data Collection (During Year 1 and 2) for Patients Receiving Ongoing 
Eculizumab .................................................................................................................50 
7.4.3.1. 
Additional Data Collection on Day 0 (Baseline)/Visit 1 for Patients 
Receiving Ongoing Eculizumab Treatment ................................................................50 
7.4.3.2. 
Additional Data Collection at the Month 3 and Month 6 Visits for Patients 
Receiving Ongoing Eculizumab Treatment ................................................................51 
7.4.3.3. 
Additional data Collection at 6 Month Visits for Patients Receiving Ongoing 
Eculizumab Treatment ................................................................................................51 
7.4.3.4. 
Visit 28 (Month 24)/End-of-Study (EOS)/Early Termination (ET) Visit for 
Patients Receiving Ongoing Eculizumab Treatment: .................................................51 
7.4.4. 
Additional Data Collection (During Year 1 and 2) for Patients Receiving 
Ongoing Eculizumab Treatment at a Reduced/Increased Dosing Regimen ...............51 
7.4.4.1. 
Additional Data Collection at the Time of Eculizumab Dose/Dosing 
Reduction/Increase .....................................................................................................52 
7.4.4.2. 
Additional Data Collection Every Month for Patients on a 
Reduced/Increased Dosing Regimen ..........................................................................52 
7.4.5. 
Data Collection for Patients After Intentional Eculizumab Treatment 
Discontinuation and After any Subsequent Intentional Discontinuation(s) ...............52 
7.4.5.1. 
Additional Data Collection at the Time of Intentional Discontinuation/Visit 
1D (2 weeks [±2 days] After the Last Eculizumab Infusion) .....................................53 
7.4.5.2. 
Additional Data Collection at V2D/Week 2, 3D/Week 4, and V7D/Month 3 
for Patients After Intentional Eculizumab Treatment Discontinuation ......................53 
7.4.5.3. 
Additional Data Collection at V7D/Month 3 and V10D/Month 6 for Patients 
After Intentional Eculizumab Treatment Discontinuation .........................................53 
7.4.5.4. 
Visit 28D/Month 24/End-of-Study (EOS)/Early Termination (ET) Visit for 
Patients After Intentional Eculizumab Treatment Discontinuation ............................54 
7.4.6. 
Data Collection for Patients who Re-initiate Eculizumab Treatment After an 
Intentional Discontinuation:  Re-initiation After the First Intentional 
Eculizumab Discontinuation and Any Subsequent Re-initiation(s) ...........................54 
7.4.6.1. 
Additional Procedures at the Time of Eculizumab Re-initiation/Visit 1R (1 
Week Prior to Re-initiation [±2 days]) .......................................................................54 
7.4.6.2. 
Additional data Collection at 6 Month Visits: Visits V10R/Month 6, 
V16R/Month 12, V22R/Month 18 for Patients who Re-initiate Eculizumab 
Treatment After an Intentional Discontinuation .........................................................54 
7.4.6.3. 
End-of-Study (EOS)/Early Termination (ET) Visit for Patients who Re-
initiate Eculizumab Treatment After an Intentional Discontinuation .........................55 
7.4.7. 
Visits at the Discretion of the Investigator .................................................................55 
7.4.8. 
Unscheduled Visits .....................................................................................................55 
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7.4.9. 
Missing Visits .............................................................................................................55 
8. 
SELECTION AND WITHDRAWAL OF PATIENTS ..............................................57 
8.1. 
Patient Participation ....................................................................................................57 
8.2. 
Inclusion Criteria ........................................................................................................57 
8.3. 
Exclusion Criteria .......................................................................................................57 
8.4. 
Patient Withdrawal Criteria ........................................................................................58 
8.4.1. 
Withdrawal of Patients From the Study......................................................................58 
8.4.2. 
Handling of Withdrawals ............................................................................................58 
8.4.3. 
Sponsor’s Termination of Study .................................................................................58 
8.4.4. 
End of Study Definition ..............................................................................................58 
9. 
STUDY ASSESSMENTS ..........................................................................................59 
9.1. 
Safety Parameters .......................................................................................................59 
9.1.1. 
Vital Signs ..................................................................................................................59 
9.1.2. 
Physical Examination .................................................................................................59 
9.1.3. 
Laboratory Tests .........................................................................................................59 
9.2. 
Assessments for TMA Manifestations ........................................................................60 
9.2.1. 
Endpoint Adjudication Committee .............................................................................60 
9.3. 
Assessments of Eculizumab Treatment and Associated Supportive 
Interventions ...............................................................................................................60 
9.4. 
Contraception ..............................................................................................................61 
9.5. 
Adverse Events ...........................................................................................................61 
9.5.1. 
Detection of Adverse Events ......................................................................................61 
9.5.2. 
Definition of an Adverse Event ..................................................................................61 
9.5.2.1. 
Abnormal Test Finding ...............................................................................................62 
9.5.2.2. 
Serious Adverse Event and SAE Criteria ...................................................................62 
9.5.2.3. 
Hospitalization ............................................................................................................63 
9.5.2.4. 
Procedures ...................................................................................................................63 
9.5.2.5. 
Events of Interest ........................................................................................................63 
9.5.2.6. 
Severity Assessment ...................................................................................................64 
9.5.2.7. 
Causality Assessment .................................................................................................64 
9.5.2.8. 
Exposure during Pregnancy and Lactation .................................................................65 
9.5.2.9. 
Withdrawal due to an AE ...........................................................................................65 
9.5.2.10. 
Reporting Period .........................................................................................................65 
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9.5.2.11. 
Reporting Requirements for AEs ................................................................................66 
9.5.2.12. 
Reporting Requirements for Non-serious AEs ...........................................................66 
9.5.2.13. 
Reporting Requirements for SAEs .............................................................................66 
9.5.2.14. 
Sponsor Reporting Requirements ...............................................................................67 
9.5.2.15. 
Investigator Reporting Requirements .........................................................................67 
9.6. 
Pharmacokinetic/Pharmacodynamic Assessments .....................................................67 
9.7. 
Genetic and Biomarker Assessments ..........................................................................67 
9.8. 
Patient Related Outcomes Assessments .....................................................................67 
10. 
SAMPLE SIZE AND STATISTICAL METHODS ...................................................68 
10.1. 
Sample Size Estimation ..............................................................................................68 
10.2. 
Statistical Methods ......................................................................................................68 
10.2.1. 
Analysis Sets ...............................................................................................................68 
10.2.2. 
General Considerations ...............................................................................................68 
10.2.3. 
Patient Disposition ......................................................................................................69 
10.2.4. 
Patient Characteristics ................................................................................................69 
10.2.5. 
Concomitant Therapy .................................................................................................69 
10.2.6. 
Treatment Compliance ................................................................................................69 
10.2.7. 
Primary Endpoint Analyses ........................................................................................69 
10.2.8. 
Secondary Endpoint Analyses ....................................................................................71 
10.2.9. 
Safety Analyses ..........................................................................................................71 
10.2.10. 
Physical Examinations and Vital Signs ......................................................................71 
10.2.11. 
Laboratory Assessments .............................................................................................72 
10.2.12. 
Exploratory Endpoint Analyses ..................................................................................72 
10.2.12.1. Pharmacokinetic/Pharmacodynamic/Biomarker Analyses .........................................72 
10.2.12.2. Genetic Analyses ........................................................................................................72 
10.2.13. 
Other Statistical Considerations .................................................................................73 
10.2.13.1. Missing or Invalid Data ..............................................................................................73 
10.2.13.2. Interim Analysis ..........................................................................................................73 
11. 
DIRECT ACCESS TO SOURCE DATA/DOCUMENTS.........................................74 
11.1. 
Study Monitoring ........................................................................................................74 
11.2. 
Data Capture System ..................................................................................................74 
11.3. 
Access to the Study Data ............................................................................................75 
11.4. 
Audits and Inspections ................................................................................................75 
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11.5. 
Institutional Review Board (IRB)/Independent Ethics Committee (IEC) ..................75 
11.6. 
Data Monitoring ..........................................................................................................75 
12. 
QUALITY CONTROL AND QUALITY ASSURANCE .........................................75 
13. 
ETHICS ......................................................................................................................76 
13.1. 
Ethics Review .............................................................................................................76 
13.2. 
Ethical Conduct of the Study ......................................................................................76 
13.3. 
Written Informed Consent ..........................................................................................77 
14. 
DATA HANDLING AND RECORDKEEPING .......................................................78 
14.1.1. 
Inspection of Records .................................................................................................78 
14.1.2. 
Retention of Records ..................................................................................................78 
14.1.3. 
Retention of Biological Samples ................................................................................78 
14.1.4. 
Data Privacy ................................................................................................................79 
15. 
PUBLICATIONS .......................................................................................................80 
16. 
REFERENCE LIST ....................................................................................................81 
APPENDIX 1. SUMMARY OF LABORATORY PANELS AND TESTS ..............................82 
APPENDIX 2. FACIT-FATIGUE ASSESSMENT FOR PEDIATRIC PATIENTS .................83 
APPENDIX 3. FACIT-FATIGUE ASSESSMENT FOR ADULT PATIENTS ........................84 
APPENDIX 4. EUROPEAN ORGANIZATION FOR RESEARCH AND 
TREATMENT OF CANCER QUALITY OF LIFE QUESTIONNAIRE 
(EORTC QLQ-C30) ...................................................................................................85 
APPENDIX 5. PATIENT-REPORTED AHUS SYMPTOMS ..................................................87 
 
LIST OF TABLES 
Table 1: 
Emergency Contact Information ...................................................................................4 
Table 2: 
List of Abbreviations and Definitions of Terms .........................................................24 
Table 3: 
Schedule of Assessments for Patients Receiving Ongoing Eculizumab 
Treatment (Recommended and Reduced/Increased Dosing Regimen) ......................34 
Table 4: 
Schedule of Assessments for Patients Who Discontinue Eculizumab .......................38 
Table 5: 
Schedule of Assessments for Patients who Re-initiate Eculizumab ...........................41 
Table 6: 
Schedule of Additional Assessments for Patients Receiving Eculizumab on a 
Reduced/Increased Dosing Regimen ..........................................................................44 
 
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LIST OF FIGURES 
Figure 1: Study Flow Diagram ......................................................................................................30 
 
  
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4. 
LIST OF ABBREVIATIONS AND DEFINITIONS OF TERMS 
The following abbreviations and specialist terms are used in this study protocol. 
Table 2: 
List of Abbreviations and Definitions of Terms  
Abbreviation or Specialist Term 
Explanation 
AE 
Adverse event 
aHUS 
Atypical hemolytic uremic syndrome 
ALT 
Alanine aminotransferase 
AST 
Aspartate aminotransferase 
ATC 
Anatomic Therapeutic Chemical 
BUN 
Blood urea nitrogen 
BP 
Blood Pressure 
CBC 
Complete blood count 
CFH 
Complement factor H 
CFI 
Complement factor I 
CKD-EPI 
Chronic kidney disease-epidemiology 
CI 
Confidence Interval 
CPK 
Creatinine phosphokinase 
cRBC 
Chicken red blood cell 
CRF 
Case report form 
EC 
Ethics Committee 
eCRF 
Electronic case report form 
EDC 
Electronic data capture 
eGFR 
Estimated glomerular filtration rate 
EIU 
Exposure in-utero 
EOI 
Events of interest 
EORTC QLQ-C30 
European Organization for Research and Treatment or Cancer quality of life 
questionnaire 
EOS 
End-of-Study 
ET 
Early termination 
FACIT 
Functional Assessment of Chronic Illness Therapy 
FAS 
Full analysis set 
GCP 
Good Clinical Practice 
HDL 
High-density lipoprotein 
HR 
Heart Rate 
ICH 
International Council on Harmonisation 
ICF 
Informed Consent Form  
ICU 
Intensive care unit 
IEC 
Independent Ethics Committee 
IPTW 
Inverse-probability treatment weighting 
IRB 
Institutional Review Board 
LDL 
Low-density lipoprotein 
LLN 
Lower limit of normal 
LDH 
Lactate dehydrogenase 
mAb 
Monoclonal antibody 
MedDRA 
Medical Dictionary for Regulatory Activities 
PD 
Pharmacodynamics 
PE 
Plasma exchange 
PI 
Plasma infusion  
PK 
Pharmacokinetics 
PRO 
Patient related outcomes 
Q2W 
Every two-weeks 
RBC 
Red blood cell 
RR 
Respiration Rate 
SD 
Standard deviation 
SOC 
System organ class 
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Abbreviation or Specialist Term 
Explanation 
SAE 
Serious adverse event 
sVCAM1 
Soluble vascular cell adhesion protein 1 
TMA 
Thrombotic microangiopathy 
TNFR1 
Tumor necrosis factor receptor 1 
ULN 
Upper limit of normal 
UNS 
Unscheduled 
WBC 
White blood cell 
 
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5. 
INTRODUCTION 
5.1. 
Overview of Atypical Hemolytic Syndrome Disease 
Atypical hemolytic uremic syndrome (aHUS) is a rare, progressive, and life-threatening disease 
that affects both children and adults (Zimmerhackl, 2006) .  Atypical hemolytic uremic 
syndrome is a disease of complement dysregulation, frequently resulting from mutations in 
complement and/or coagulation pathway genes or auto-antibodies against complement proteins.  
Specific genetic complement mutations or antibodies are only currently identifiable in 
approximately 50% to 70% of patients diagnosed with aHUS (Noris, 2010; Matis, 1995) .  
Chronic uncontrolled terminal complement activation causes complement-mediated thrombotic 
microangiopathy (TMA), a pro-thrombotic and pro-inflammatory state (Matis, 1995; Karpman, 
2006) , characterized by endothelial cell activation, the release of von Willebrand factor, platelet 
activation and aggregation, leukocyte recruitment and a pro-coagulant state (Ballermann, 1998) .  
The prognosis in aHUS is poor with more than half of all patients dying, requiring dialysis, or 
having permanent kidney damage within 1 year of diagnosis  (Caprioli, 2006) .   
Eculizumab is a high affinity humanized monoclonal antibody (mAb) that binds to and blocks 
the cleavage of C5 into the inflammatory, pro-thrombotic end molecule C5a and lytic membrane 
attack complex, C5b-9, leaving the upstream components of complement, most notably C3b, 
intact.  Uncontrolled complement activation observed in aHUS patients coupled with the 
established activity of eculizumab to selectively inhibit terminal complement activation provided 
a mechanistic rationale for the evaluation of eculizumab in the treatment of aHUS.  Eculizumab 
is approved for the treatment of aHUS in 39 countries, including the European Union and the 
USA in 2011, and Australia in 2012.   
There is growing but limited information on the long-term clinical status of aHUS patients who 
have previously received or are continuing to receive treatment with eculizumab.  An 
observational registry study (M11-001 aHUS Registry) designed to collect clinical data to 
provide insight into the long-term outcomes of patients with aHUS and fulfill post-marketing 
commitments is ongoing.  This study (ECU-aHUS-403) aims to provide greater insight into risk 
factors for manifestations of TMA in patients with aHUS and risk of disease progression in 
relationship to standard of care treatment (defined as eculizumab approved treatment). 
5.2. 
Rationale for the Study Design 
Several recent consensus papers regarding aHUS treatment clearly mention eculizumab as a part 
of the standard of care, and recommend its use as first-line treatment in many situations (Zuber, 
2012; Campistol, 2013; Loirat, 2016; Nester, 2015) .  In order to provide further guidance on the 
chronicity of treatment in patients with aHUS, this study aims to assess TMA manifestations in 
in relationship to treatment.  This study will also seek to identify predictors of TMA 
manifestations, including genetic profile, and to further elucidate mechanisms of disease and 
response to treatment through biomarker assessment.  Finally, long-term effects on kidney 
function in relationship to treatment and other factors will also be assessed. 
This is a real-world study and as such, all treatment decisions will be left to the Treating 
Physician’s discretion. 
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5.3. 
Rationale for Genetic and Biomarker Testing 
It is widely recognized that aHUS is associated with genetic or acquired defects in genes of the 
complement pathway.  Recent sequencing efforts have also identified additional pathogenic 
mutations in genes of the coagulation pathway (Bu, 2014).  Mutational analysis of genes known 
to be associated with aHUS informs not only the disease process as likely complement-mediated, 
but also provides therapeutic and prognostic information in aHUS patients with regards to risk of 
progression, risk of relapse, and risk of recurrence.  As the known pathogenic mutations can be 
identified in about one half of aHUS patients, additional pathogenic variants likely exist.  
Uncovering these novel variants will help advance our understanding of the disease 
pathogenesis.  The goal of the genetic analysis is two-fold.  First, known variants associated with 
aHUS will be analyzed in the patient population and the results will be communicated to the 
Investigators, which may be relayed also to the Treating Physicians, to inform patient 
management and treatment decisions.  In addition, patients will also be evaluated for 
autoantibodies directed against complement factor I (CFI) and complement factor H (CFH); 
these results will also be provided to the Treating Physicians.  Secondly, additional exploratory 
genetic analyses may be performed to identify novel variants associated with aHUS or disease 
modifying genes.  This exploratory analysis may enable better, more rapid diagnosis of aHUS, a 
better understanding of the heterogeneity of the disease, and may help to identify those patients 
who are at highest risk of disease progression.  The results of the exploratory analysis will not be 
provided to the Investigator.   
In addition to genetic markers of disease, analysis of biomarkers of complement pathway 
proteins and biomarkers of disease progression will further advance our understanding of both 
the mechanisms of disease and the ability of eculizumab to act on these mechanisms.  Levels of 
free C5 and functional assays of terminal complement activity are expected to provide a better 
understanding of the relationship between eculizumab levels and complement-mediated injury.  
Exploratory biomarkers of complement alternative pathway activation (eg, Ba), coagulation (eg, 
D-dimer), inflammation (eg, TNFR1), endothelial activation (eg, sVCAM-1), endothelial 
damage (eg, thrombomodulin), renal injury (eg, cystatin C), and other markers of complement 
activation or disease progression may be performed to help elucidate the level of ongoing 
alternative pathway activation and the effect of eculizumab on complement, inflammation, and 
coagulation signaling networks and resultant endothelial injury and tissue damage.  The series of 
exploratory tests to be done may differ based on the study time point, eg the biomarkers 
performed during a TMA may differ in order to explore the specific changes caused by disease 
manifestation.  This exploratory analysis will also evaluate whether the underlying mechanisms 
of disease are affected when eculizumab treatment is discontinued.  The biomarker analyses are 
exploratory and these results will not be provided to the Investigator. 
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17 November 2016 
6. 
STUDY OBJECTIVES AND PURPOSE 
The main purpose of this study is to assess TMA disease manifestations in patients with aHUS 
with or without ongoing eculizumab treatment in a real-world setting.  The study hypothesis is 
that the rate of TMA manifestation will be highest during periods of eculizumab treatment 
discontinuation.  
Additional objectives of this study are to evaluate potential clinical predictors of disease 
manifestation and progression, including clinical characteristics and genetic profiling to evaluate 
disease activity and relationship to treatment as determined by levels of biomarkers associated 
with complement activation, and the use of associated supportive interventions such as plasma 
exchange/plasma infusion (PE/PI), dialysis, blood transfusions, and renal transplantation. 
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7. 
INVESTIGATIONAL PLAN  
Study (ECU-aHUS-403) is a prospective, non-randomized, open-label cohort study of patients 
with aHUS enrolled in the M11-001 aHUS Registry and currently receiving eculizumab with no 
prior intentional eculizumab discontinuations at any time (ie, not occasional, unplanned, or 
temporary missed doses of eculizumab, but intended long-term discontinuation).  The study will 
assess disease manifestation in patients receiving ongoing eculizumab treatment compared to 
those who intentionally discontinue eculizumab treatment.  This is an open-label study with no 
randomization performed for patients.  Treatment for aHUS will remain observational and at the 
discretion of the Treating Physician. 
7.1. 
Overall Study Design and Plan Description 
Approximately, 330 eligible patients, not to exceed 340 patients, currently enrolled or to enroll in 
the M11-001 aHUS Registry are expected to participate in this study.  Patients will enroll via 
competitive enrollment (ie, as patients become available at the site).  Treatment is provided at the 
Treating Physician’s discretion, therefore intentional discontinuation of eculizumab and re-
initiation of eculizumab may occur during the study.  At the Treating Physician’s discretion, 
some patients may receive a reduced/increased eculizumab dosing regimen (ie, 
reduced/increased dose and/or reduced/increased frequency of eculizumab).   
Patients receiving ongoing eculizumab treatment (whether dosed as recommended in product 
labeling or on a reduced/increased dosing regimen) without any intentional eculizumab 
discontinuation, will have assessments every 2 weeks (Q2W) through Week 10 and monthly 
assessments thereafter beginning at Month 3 to Month 24, a period of 2 years, at which time they 
will complete the study (Figure 1).   
Patients intentionally discontinued from eculizumab treatment before reaching Month 24 of 
eculizumab treatment, will commence a new schedule of assessments, immediately following the 
intentional discontinuation through 2 years from the time of their first intentional eculizumab 
discontinuation at which time they will complete the study (Figure 1).  The 2-year assessment 
period will commence 2 weeks after the last eculizumab infusion and this 2-year assessment 
period following intentional discontinuation will not change if eculizumab treatment is 
re-initiated, ie, patients who re-initiate eculizumab after an intentional discontinuation will 
complete the study 2 years from the time of their first intentional eculizumab discontinuation 
(Figure 1).  Consequently, the maximum possible time on the study for any patient is 
approximately 47 months, comprising 23 months of continuous eculizumab treatment, followed 
by an intentional discontinuation and another 24 months of study assessments, which may 
include periods of eculizumab re-initiation and subsequent intentional discontinuation of 
eculizumab treatment.   
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17 November 2016 
 
Figure 1: Study Flow Diagram 
 
 
Prior to initiating any study procedure, the informed consent form (ICF) will be signed by the 
patient or patient’s guardian and inclusion/exclusion criteria are obtained and evaluated.  At 
Day 0 (Baseline)/Visit 1, the patient will be assessed for study eligibility through medical history 
review, demographic data, and safety assessments (vital signs, physical examination, laboratory 
tests, assessments of TMA manifestations, eculizumab treatment status, and associated 
supportive interventions, adverse events [AEs], concomitant medications/therapies).  Patient-
reported outcomes (PRO) using Functional Assessment of Chronic Illness Therapy (FACIT)-
Fatigue instrument, European Organization for Research and Treatment of Cancer quality of life 
questionnaire (EORTC QLQ-C30), and specific patient-reported aHUS symptoms will be 
assessed.   
On Day 0 (Baseline)/Visit 1, safety assessments will be performed prior to blood or urine sample 
collection for biomarker tests.  Blood samples for cRBC hemolytic assay, free C5, and 
pharmacokinetics (PK) will be collected.  Samples for genetic testing will be collected from 
patients during the study at this visit or any other visit thereafter.  A patient may be allowed to 
opt-out from providing a sample for genetic testing (eg, for religious reasons) and still participate 
in the study.  Patient-reported outcomes using FACIT-Fatigue instrument, EORTC QLQ-C30, 
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and specific patient-reported aHUS symptoms will be assessed.  Blood and urine for laboratory 
tests should be collected 5 to 90 minutes prior to administration of eculizumab.  
7.1.1. 
Study Year 1 and 2 - Patients Receiving Ongoing Eculizumab Treatment 
After completing the Day 0 (Baseline)/Visit 1, patients will return to the site for Q2W study 
visits from Week 2 through Week 10 (Visit 2 through Visit 6), followed by monthly study visits 
until the end of the study (Figure 1).   
Patients receiving ongoing eculizumab treatment will have monthly study visits beginning at 
Month 3 (Visit 7) through Month 24 (Visit 28), see Table 3.  If a patient completes all the Study 
Visits (Visits 1 through Visit 27), then Visit 28, will be the end-of-study (EOS) visit, at which 
time the patient completes the study.  Safety assessments will be performed at every visit prior to 
collection of samples for biomarker analyses and administration of eculizumab.  Blood and urine 
samples for biomarkers will be collected at every visit (Table 3).  Samples for genetic testing 
will be collected from patients on Day 0 (Baseline)/Visit 1 however, may alternatively be 
collected at any other visit during the study after Day 0 (Baseline). Patient-reported outcomes 
using FACIT-Fatigue instrument, EORTC QLQ-C30, and specific patient-reported aHUS 
symptoms will be assessed on Day 0 (Baseline)/Visit 1, Month 3 (Visit 7), and Month 6 
(Visit 10) (Table 3).  Blood and urine for laboratory tests should be collected 5 to 90 minutes 
prior to administration of eculizumab.  If the scheduled eculizumab dose falls within a study visit 
window, the study visit should be scheduled on the same day of the dose or within 48 hours prior 
to the dose, such that laboratory samples can be taken prior to the eculizumab dose. If the 
scheduled dose falls on the same day as the scheduled visit, blood samples are to be taken 5 to 
90 minutes prior to administration.  It is preferred that the dose is scheduled on the same day as 
the visit, if possible. 
For all patients receiving eculizumab, blood samples for free C5, PK, and cRBC hemolytic assay 
will be collected every 6 months beginning at Month 6 (Visit 10) through Month 24 (Visit 28) 
(Table 3).  For patients receiving eculizumab at a reduced/increased eculizumab dosing regimen, 
additional blood samples for free C5, PK, and cRBC hemolytic assay will be collected at the 
time of dose reduction and monthly thereafter as long as the patient continues to be on that 
reduced/increased eculizumab dosing regimen.  If a patient enters the study on a 
reduced/increased eculizumab dosing regimen, blood samples for free C5, PK, and cRBC 
hemolytic assay will be collected monthly as long as the patient remains on a reduced/increased 
eculizumab dosing regimen (Table 6). 
If a patient experiences a TMA manifestation, 2 TMA visits will be performed; the 1st TMA visit 
(Visit 1T) will be conducted as soon as possible on recognition of signs and symptoms of TMA 
manifestation onset by the Investigator.  A 2nd TMA visit (Visit 2T) should be performed within 
2 weeks of the first visit.  Assessments and sample collection as specified in TMA Visits 
(Visit 1T and Visit 2T) in Table 3 will be performed. 
Additional blood and/or urine samples may be collected as needed, at scheduled or unscheduled 
visits at the discretion of the Investigator.   
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7.1.2. 
Study Year 1 and 2 – Patients Who Discontinue Eculizumab 
First Intentional Eculizumab Discontinuation:  
Following the first intentional eculizumab discontinuation, patients will have a study visit 
(Visit 1D) within 2 weeks (±2 days) after the last eculizumab infusion followed by Q2W study 
visits from Week 2 through Week 10 (Visit 2D through Visit 6D) (Table 4).  Beginning at Month 
3 (Visit 7D), patients will have monthly study visits for a total of 2 years (Visit 7D-28D).  If a 
patient completes all the Study Visits (Visits 1D through Visit 27D), then Visit 28D will be the 
EOS visit, at which time the patient completes the study (Table 4). 
At the study visit (Visit 1D), on the date of first intentional eculizumab discontinuation, safety 
assessments will be performed prior to collecting samples for biomarker tests.  At the Q2W study 
visits (Visit 2D through Visit 6D), safety assessments will be performed prior to collecting blood 
and urine samples for biomarker tests.  During these Q2W study visits, blood samples for cRBC 
hemolytic assay, free C5, and PK will be collected at time points specified in (Table 4). 
At monthly visits beginning at Month 3 (Visit 7D) through Month 24 (Visit 28D/EOS), monthly 
safety assessments will be performed prior to collecting blood and urine samples for biomarker 
tests.  Blood samples for cRBC hemolytic assay, free C5, and PK will be collected at Month 3 
and Month 24/EOS after intentional discontinuation of eculizumab as specified in Table 4.  
Blood and urine for laboratory tests should be collected 5 to 90 minutes prior to administration of 
eculizumab. 
Patient-reported outcomes using FACIT-Fatigue instrument, EORTC QLQ-C30, and specific 
patient-reported aHUS symptoms will be assessed at the study visit (Visit 1D), Month 3 (Visit 
7D), and Month 6 (Visit 10D). 
If a patient experiences a TMA manifestation, 2 TMA visits will be performed; the 1st TMA visit 
(Visit 1TD) will be conducted as soon as possible on recognition of signs and symptoms of TMA 
manifestation onset by the Investigator.  A 2nd TMA visit (Visit 2TD) should be performed 
within 2 weeks of the first visit.  Assessments and sample collection as specified in TMA Visits 
(Visit 1TD and Visit 2TD) in Table 4 will be performed.   
Additional blood and/or urine samples may be collected as needed, at scheduled or unscheduled 
visits at the discretion of the Investigator or Treating Physician.   
Subsequent Intentional Eculizumab Discontinuation(s):  
For any subsequent intentional eculizumab discontinuation, patients will follow the assessments 
as specified in Visit 1D as with the first intentional eculizumab discontinuation followed by 
Q2W study visits thereafter as specified in Visit 2D through 6D (Table 4).  Patients will have 
monthly visits beginning at Month 3 after intentional eculizumab discontinuation for a total of 
2 years (24 months) from the time of the first intentional eculizumab discontinuation (Table 4).  
The monthly visits will follow the schedule as determined by the date of their first intentional 
eculizumab discontinuation.   
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7.1.3. 
Study Year 1 and 2 –Patients Who Re-initiate Eculizumab  
Re-initiation After the First Intentional Eculizumab Discontinuation: 
Patients who re-initiate eculizumab will have a study visit within 1 week prior to re-initiation of 
eculizumab (Visit 1R).  At Visit 1R, safety assessments will be performed prior to collecting 
blood and urine samples for biomarker tests.  Blood samples will be collected for cRBC 
hemolytic assay, free C5, and PK (Table 5).   
After Visit 1R, patients will have Q2W study visits from Week 2 through Week 10 (Visit 2R 
through Visit 6R) as specified in Table 5.  Patients will have monthly study visits beginning at 
Month 3 through up to 2 years after the time of the first intentional eculizumab discontinuation.  
These monthly visits will follow the schedule as determined by the date of the first intentional 
eculizumab discontinuation.  At these monthly visits, safety assessments will be performed prior 
to collection of samples for biomarker analyses.  Blood samples for cRBC hemolytic assay, free 
C5, PK will be collected at time points specified in Table 5.   
If a patient experiences a TMA manifestation, 2 TMA visits will be performed; the first TMA 
visit (Visit 1TR) will be conducted as soon as possible on recognition of signs and symptoms of 
TMA manifestation onset by the Investigator.  A 2nd TMA visit (Visit 2TR) should be performed 
within 2 weeks of the first visit.  Assessments and sample collection as specified in TMA Visits 
(Visit 1TR and Visit 2TR) in Table 5 will be performed.   
Additional blood and/or urine samples may be collected as needed, at scheduled or unscheduled 
visits at the discretion of the Investigator or Treating Physician.  Scheduled visits, when 
overlapping with other visits (eg, TMA visit, re-initiation visits), can be combined as 
appropriate. 
Re-initiation After the Subsequent Intentional Eculizumab Discontinuation(s): 
Similarly, for any subsequent eculizumab re-initiation, patients will have a re-initiation study 
visit within 1 week prior to re-initiation of eculizumab and follow the assessments as specified in 
Visit 1R (Table 5), Q2W study visits as specified in Visit 2R through Visit 6R, and monthly 
study visits thereafter for a total of 2 years from the time of the first intentional eculizumab 
discontinuation (ie, 2 years from Visit 1D).  These monthly visits will follow the original 
schedule as determined by the data of the first intentional eculizumab discontinuation.  
 
 
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7.2. 
Schedule of Assessments 
Table 3: 
Schedule of Assessments for Patients Receiving Ongoing Eculizumab Treatment (Recommended and 
Reduced/Increased Dosing Regimen) 
 
Baseline 
Q2W (±2 days) 
Visits (Wk 2 
through Wk 10) 
Monthly (± 1 week) Visits for Patients Receiving Ongoing Eculizumab Treatmenta 
Month 3 through Month 24 (Year 2)b 
Study Visits 
V1 
V2 
V3 
V4 –
V6 
V7 – 
V9 
V10 
V11 -
V15 
V16 
V17 –
V21 
V22 
V23-
V27 
V28/ 
EOS*/
ET** 
TMA 
Visit 
+UNS 
Visit 
Days/Months 
Day 0 
Wk 
2 
Wk 
4 
Wk 6-
Wk 10 
M3 - 
M5 
M6 
M7 - 
M11 
M12 
M13-
M17 
M18 
M19-
M23 
M24 
^1T 
^^2T 
 
Study Assessments/Procedures 
Informed Consentc 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Inclusion/ Exclusion 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Medical historyd 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Demographics 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Safety Assessments/Blood and Urine Samples for Laboratory Testse 
Vital Signs 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Heightf and Weight 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Complete Physical Examinationg 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
AEs 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Concomitant 
Medication/Therapy 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Laboratory Testsh 
Hematology 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Blood Chemistry 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Urinalysis 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Assessment of TMA manifestationi 
Changes in Specific Laboratory 
Parameters 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Renal Signs and Symptoms 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Extra-renal Signs and Symptoms 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
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Table 3: 
Schedule of Assessments for Patients Receiving Ongoing Eculizumab Treatment (Recommended and 
Reduced/Increased Dosing Regimen (Continued) 
Baseline 
Q2W (±2 days) 
Visits (Wk 2 
through Wk 10) 
Monthly (± 1 week) Visits for Patients Receiving Ongoing Eculizumab Treatmenta 
Month 3 through Month 24 (Year 2) b 
Study Visits 
V1 
V2 
V3 
V4 –
V6 
V7 – 
V9 
V10 
V11 -
V15 
V16 
V17 –
V21 
V22 
V23-
V27 
V28/ 
EOS*/
ET** 
TMA 
Visit 
+UNS
Visit
Days/Months 
Day 0 
Wk 
2 
Wk 
4 
Wk 6-
Wk 10 
M3 - 
M5 
M6 
M7 - 
M11 
M12 
M13-
M17 
M18 
M19-
M23 
M24 
^1T 
^^2T 
Assessment of Eculizumab Treatment and Associated Supportive Interventionsj 
Eculizumab Treatment Log 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
PE/PI 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Dialysis 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Blood Transfusion 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Renal Transplantation 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Blood/Urine Samples for Genetic and Biomarker Analyses 
Genetic Testsk 
X 
Biomarker Testsl 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Blood samples for the following 
cRBC Hemolytic assaym 
X 
X 
X 
X 
X 
X 
X 
Free C5m 
X 
X 
X 
X 
X 
X 
X 
PKn 
X 
X 
X 
X 
X 
X 
X 
PRO Assessmentso 
FACIT-Fatigue 
X 
M3 
only 
X 
EORTC QLQ-C30 
X 
M3 
only 
X 
Specific patient reported aHUS 
symptoms 
X 
M3 
only 
X 
Additional samplesp 
At the Discretion of the Investigator, additional/more frequent samples may be collected at Scheduled Study Visits/Unscheduled Visits 
Abbreviations: AE = adverse event; cRBC = chicken red blood cell; EIU = exposure in-utero; EORTC QLQ-C30 = European Organization for Research and 
Treatment of Cancer quality of life questionnaire; EOS = end-of-study; ET = early termination; FACIT-Fatigue = Functional Assessment of Chronic Illness 
Therapy Fatigue scale; PE/PI = plasma exchange/plasma infusion; T = trough sample; TMA = thrombotic microangiopathy; PK  = pharmacokinetics; UNS = 
unscheduled visit 
* If a patient completes all the Study Visits (Visits 1-28), Visit 28, the last Study Visit will be the end-of-study (EOS) visit, at which time the patient completes
the study.
** If a patient withdraws early from the study during the Study Visits (Visits 1-28), an Early Termination (ET) Visit will be performed. 
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^ If a patient experiences a TMA manifestation as defined in Section 7.3, the TMA visit (Visit 1T) must be performed as soon as possible of symptom onset.  
Additional evaluation visits can be scheduled at the discretion of the investigator. 
^^ The TMA visit (Visit 2T) must be performed within 2 weeks (±2 days) of Visit 1T. 
+ Unscheduled visit and procedures will be performed at the Investigator’s discretion and results will be recorded in the eCRF. 
a Treatment in this study is provided at the Treating Physician’s discretion.  Some patients may receive a reduced/increased eculizumab dosing regimen. All 
assessments and procedures will be performed prior to administration of eculizumab.  If a patient’s dose is reduced/increased after enrolling in the study, study 
assessments as specified in Section 7.4.2.2 and Table 6 will be performed at a Study Visit (UNS) at least 2 days prior to the visit when the reduced/increased 
eculizumab dosing regimen will be administered. 
b Patients receiving ongoing eculizumab treatment (recommended or reduced/increased dosing regimen) without any intentional eculizumab discontinuation will 
have monthly assessments performed beginning at Month 3 to Month 24, a period of 2 years, at which time they will complete the study. Monthly visits are 
defined as every 28 days ie, every 4 weeks. 
c On Day 0 (Baseline), patient or patient’s guardian sign the informed consent.  Patient or patient’s parent/legal guardian must be willing and able to give written 
informed consent and the patient (if minor) must be willing to give written informed assent. 
d Medical history data should be reviewed in order to determine eligibility, and this review should be documented; however, medical history data are only to be 
reported in the M11-001 Registry database and not through this study’s database. 
e Safety assessments (ie, vital signs, physical examination, laboratory tests, assessments of TMA manifestations and associated supportive interventions, AEs, 
and concomitant medications/therapies) will be collected at the specified clinic visits prior to sample collection for biomarker tests.  For a summary of clinical 
laboratory tests see Appendix 1.  In addition, pregnancy-, lactation-, and follow-up-data on neonates for 3 months after delivery, especially when the neonate 
has experienced eculizumab EIU, will also be collected. 
f Height will be collected for adult patients only at Day 0 (Baseline). Height will be collected for pediatric patients at every visit. 
g A complete physical examination will be performed only at Day 0 (Baseline).. 
h Laboratory tests will include platelet count, serum albumin, serum LDH, serum creatinine, hemoglobin, haptoglobin, total bilirubin, full CBC, and urinalysis.  
Blood and urine for laboratory tests should be collected 5 to 90 minutes prior to administration of eculizumab.  For patients on eculizumab, if the scheduled 
dose falls within a study visit window, the study visit should be scheduled on the same day of the dose or within 48 hours prior to the dose, such that laboratory 
samples can be taken prior to the eculizumab dose. If the dose falls on the same day as the scheduled visit, blood samples are to be taken 5 to 90 minutes prior 
to administration.  It is preferred that the dose is scheduled on the same day as the visit, if possible.  Among patients receiving PE/PI or dialysis, blood and 
urine samples for laboratory tests will be collected prior to initiation of PE/PI or dialysis. 
i TMA manifestation assessments of aHUS including renal and extra-renal manifestations. 
j Associated supportive interventions including PE/PI, dialysis, blood transfusion, and renal transplantation. Among patients receiving PE/PI or dialysis, samples 
for analyses and assessments will be collected prior to initiation of PE/PI or dialysis. 
k Sample for genetic testing will be collected on Day 0 (Baseline) of the study however, may alternatively be collected at any other visit after Day 0 (Baseline) 
during the study.  A patient may be allowed to opt-out from providing a sample for genetic testing (eg, for religious reasons) and still continue to participate in 
the study. 
l At Day 0 (Baseline), blood and urine samples collected for genetic and biomarker analysis should be collected after safety assessments have been performed 
and prior to administration of eculizumab.  For all other time points, samples for biomarker analyses should be collected after safety assessments have been 
performed and prior to administration of eculizumab.  Among patients receiving PE/PI or dialysis, blood and urine samples will be collected prior to initiation 
of PE/PI or dialysis.  Unused samples will be stored for future analysis (see Section 14.1.3). 
m For all patients receiving eculizumab, blood samples for cRBC hemolytic assay and free C5 will be collected every 6 months beginning at Month 6 (Visit 10) 
through Month 24 (Visit 28).  For patients receiving eculizumab at a reduced/increased eculizumab dosing regimen, additional trough blood samples for cRBC 
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hemolytic assay and free C5 will be collected at the time of dose reduction and monthly thereafter until the patient continues to be on that reduced/increased 
eculizumab dosing regimen (see Schedule of Assessments provided in Table 6). 
n Trough blood samples for PK tests are to be taken 5 to 90 minutes prior to administration of eculizumab.  For patients on eculizumab, if the scheduled dose 
falls within a study visit window, the study visit should be scheduled on the same day of the dose or within 48 hours prior to the dose, such that laboratory 
samples can be taken prior to the eculizumab dose. If the dose falls on the same day as the scheduled visit, blood samples are to be taken 5 to 90 minutes prior 
to administration.  It is preferred that the dose is scheduled on the same day as the visit, if possible.  For all patients receiving eculizumab, blood samples for 
PK will be collected every 6 months beginning at Month 6 (Visit 10) through Month 24 (Visit 28).  For patients receiving eculizumab at a reduced/increased 
eculizumab dosing regimen, additional blood samples for PK will be collected at the time of dose reduction and monthly thereafter until the patient continues to 
be on that reduced/increased eculizumab dosing regimen (see Schedule of Assessments provided in Table 6). 
o Using FACIT-Fatigue (Appendix 2 and Appendix 3), EORTC QLQ-C30 (Appendix 4), and patient-reported aHUS symptoms (Appendix 5), PRO assessments 
will be performed. 
p If a patient is experiencing a TMA manifestation additional blood samples may be collected at scheduled clinical visits/unscheduled visits, at the discretion of 
the Investigator. 
 
 
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Table 4: 
Schedule of Assessments for Patients Who Discontinue Eculizumab 
 
Patients Who Discontinue Eculizumab Treatmenta,b 
 
At Discontinuation 
(Within 2 Wks [±2 
days] after last 
eculizumab dose)c 
Q2W (±2 days) after 
DC (Wk 2 through 
Wk 10) 
Monthly (± 1 week) Visits 
Month 3 through Month 24 (Year 2) 
Study Visits 
V1D 
V2D 
V3D 
V4D –
V6D 
V7D 
V8D 
–V9D 
V10D 
Visit 11D 
through Visit 
27D 
28D/ 
EOS* 
/ET** 
TMA 
+UNS 
Visit 
Study Month/Week 
Day 0 
Wk 
2 
Wk 
4 
Wk 6-
Wk 10 
M3 
M4 
M5 
M6 
Month 7 through 
Month 23 
Month 
24 
^1TD 
^^2TD 
 
Safety Assessmentsd 
Vital Signs 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Heighte and Weight 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
AEs 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Concomitant 
Medication/Therapy 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Laboratory Testsf 
Hematology 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Blood Chemistry 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Urinalysis 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Assessments of TMA Manifestationsg 
Changes in Specific 
Laboratory Parameters 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Renal Signs and 
Symptoms 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Extra-renal Signs and 
Symptoms 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Assessment of Eculizumab Treatment and Associated supportive interventionsh 
Eculizumab Treatment 
Log 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
PE/PI 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Dialysis 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Blood Transfusion 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
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17 November 2016 
Table 4: 
Schedule of Assessments for Patients Who Discontinue Eculizumab (Continued) 
 
Patients Who Discontinue Eculizumab Treatmenta,b 
 
At Dc 
(Within 2 Wks 
[±2 days] from 
last eculizumab 
dose)c 
Q2W (±2 days) after 
DC (Wk 2 through 
Wk 10) 
Monthly (± 1 week) Visits 
Month 3 through Month 24 (Year 2) 
Study Visits 
V1D 
V2D 
V3D 
V4D –
V6D 
V7D 
V8D 
–V9D 
V10D 
Visit 11D 
through Visit 
27D 
28D/ 
EOS* 
/ET** 
TMA 
 
+UNS 
Visit 
Study Month/Week 
Day 0 
Wk 
2 
Wk 
4 
Wk 6-
Wk 10 
M3 
M4 
M5 
M6 
Month 7 through 
Month 23 
Month 
24 
^1TD 
^^2TD 
 
Renal Transplantation 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Blood/Urine Samples for Genetic and Biomarker Analyses 
Genetic Testsi 
 
 
 
 
 
 
 
 
 
 
 
 
Biomarker Testsj 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
Blood samples for the following 
cRBC Hemolytic assayk 
X 
X 
X 
 
X 
 
 
 
X 
X 
X 
 
Free C5k 
X 
X 
X 
 
X 
 
 
 
X 
X 
X 
 
PKl 
X 
X 
X 
 
X 
 
 
 
X 
X 
X 
 
PRO Assessmentsm 
FACIT-Fatigue 
X 
 
 
 
X 
 
X 
 
 
 
 
 
EORTC QLQ-C30 
X 
 
 
 
X 
 
X 
 
 
 
 
 
Specific patient reported aHUS 
symptoms 
X 
 
 
 
X 
 
X 
 
 
 
 
 
Additional samplesn 
At the Discretion of the Investigator, additional/more frequent samples may be collected at Scheduled Study Visits/Unscheduled Visits 
Abbreviations: AE = adverse event; cRBC = chicken red blood cell; EIU = exposure in-utero; EORTC QLQ-C30 = European Organization for Research and 
Treatment of Cancer quality of life questionnaire; EOS = end-of-study; ET = early termination; FACIT-Fatigue = Functional Assessment of Chronic Illness 
Therapy Fatigue scale; PE/PI = plasma exchange/plasma infusion; T = trough sample; TMA = thrombotic microangiopathy; PK  = pharmacokinetics; UNS = 
unscheduled visit 
*  
If a patient completes all the Study Visits (Visits 1D-28D), Visit 28D, the last Study Visit will be the end-of-study (EOS) visit, at which time the patient 
completes the study.   
** If a patient withdraws early from the study during the Study Visits (Visits 1D-28D), an Early Termination (ET) Visit will be performed.   
^  
If a patient experiences a TMA manifestation as defined in Section 7.3, the TMA visit (Visit 1TD) must be performed as soon as possible of symptom onset.  
Additional evaluation visits can be scheduled at the discretion of the investigator. 
^^ The TMA visit (Visit 2TD) must be performed within 2 weeks (±2 days) of Visit 1TD. 
+ Unscheduled visit and procedures will be performed at the Investigator’s discretion and results will be recorded in the eCRF. 
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a Patients who discontinue eculizumab will have monthly study visits for 2 years after the time of the first intentional eculizumab discontinuation. Q2W visits are 
defined as every 2 weeks ie, every 14 days.  Monthly visits are defined as every 28 days ie, every 4 weeks. 
b Reasons for intentional eculizumab treatment discontinuation will be systematically collected. 
c Following the first intentional eculizumab discontinuation, patients will have a study visit within 2 weeks (±2 days) after the last eculizumab infusion. 
d Safety assessments (ie, vital signs, physical examination, laboratory tests, assessments of TMA manifestations and associated supportive interventions, AEs, 
and concomitant medications/therapies) will be collected at the specified clinic visits prior to sample collection for biomarker tests.  For a summary of clinical 
laboratory tests see Appendix 1.  In addition, pregnancy-, lactation-, and follow-up-data on neonates for 3 months after delivery, especially when the neonate 
has experienced eculizumab EIU, will also be collected. 
e Height will be collected ONLY for pediatric patients. 
f Laboratory tests will include platelet count, serum albumin, serum LDH, serum creatinine, hemoglobin, haptoglobin, total bilirubin, full CBC, and urinalysis.  
Among patients receiving PE/PI or dialysis, blood and urine samples for laboratory tests will be collected prior to initiation of PE/PI or dialysis. 
g TMA manifestation assessments of aHUS including renal and extra-renal manifestations. 
h Associated supportive interventions including PE/PI, dialysis, blood transfusion, and renal transplantation.  Among patients receiving PE/PI or dialysis, 
samples for analyses and assessments will be collected prior to initiation of PE/PI or dialysis. 
i Sample for genetic testing will be collected on Day 0 (Baseline) of the study however, may alternatively be collected at any other visit after Day 0 (Baseline) 
during the study.  A patient may be allowed to opt-out from providing a sample for genetic testing (eg, for religious reasons) and still continue to participate in 
the study.  
j Samples for biomarker analyses should be collected after safety assessments have been performed.  Among patients receiving PE/PI or dialysis, samples for 
analyses and assessments will be collected prior to initiation of PE/PI or dialysis.  Unused samples will be stored for future analysis (see Section 14.1.3). 
k Blood samples for cRBC hemolytic assay and free C5 will be collected as specified until 2 years after the first intentional eculizumab discontinuation. 
l Blood samples for PK will be collected as specified until 2 years after the first intentional eculizumab discontinuation.  Samples will not be evaluated for PK 
once levels of eculizumab are no longer detectable.  Unused samples will be stored for future analysis (see Section 14.1.3). 
m Using FACIT-Fatigue (Appendix 2 and Appendix 3), EORTC QLQ-C30 (Appendix 4), and patient-reported aHUS symptoms (Appendix 5), PRO assessments 
will be performed. 
n If a patient is experiencing a TMA manifestation additional blood samples may be collected at scheduled clinical visits/unscheduled visits, at the discretion of 
the Investigator. 
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17 November 2016 
Table 5: 
Schedule of Assessments for Patients who Re-initiate Eculizumab 
Patients Who Re-initiate Eculizumab Treatmenta,b 
 
Prior to Re-initiation 
of Eculizumab 
(within 1 week prior) 
Q2W (±2 days) after 
Re-initiation  
Wk 2 through Wk 10 
Monthly (± 1 week) Visits, 
following schedule in Table 2 
Determined by the Date of 
First Intentional Eculizumab 
Discontinuation 
Patients Who 
Completed Monthly 
Study Visits For 
2 Years After the 
First Intentional 
eculizumab 
discontinuation 
 
 
Study Visits 
Visit 1R 
V2R – V6R (Wk 2 
through Wk 10 
[±2 days] after Re-
initiation) 
Monthly from Visit 7R 
Through Up to 2 Years After 
the First Intentional 
eculizumab discontinuation 
Visit 
EOS* 
/ET** 
TMA 
+UNS 
Visit 
^1TR 
^^2TR 
Safety Assessmentsc 
Vital Signs 
X 
X 
X 
X 
X 
 
 
Heightd and Weight 
X 
X 
X 
X 
X 
 
 
AEs 
X 
X 
X 
X 
X 
 
 
Concomitant 
Medication/Therapy 
X 
X 
X 
X 
X 
 
 
Laboratory Testse 
Hematology 
X 
X 
X 
X 
X 
 
 
Blood Chemistry 
X 
X 
X 
X 
X 
 
 
Urinalysis 
X 
X 
X 
X 
X 
 
 
Assessment of TMA manifestationsf 
Changes in Specific Laboratory 
Parameters 
X 
X 
X 
X 
X 
 
 
Renal Signs and Symptoms 
X 
X 
X 
X 
X 
 
 
Extra-renal Signs and Symptoms 
X 
X 
X 
X 
X 
 
 
Associated supportive interventionsg 
Eculizumab Treatment Log 
X 
X 
X 
X 
X 
 
 
PE/PI 
X 
X 
X 
X 
X 
 
 
 
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17 November 2016 
Table 5: 
Schedule of Assessments for Patients who Re-initiate Eculizumab (Continued) 
Patients Who Re-initiate Eculizumab Treatment 
 
Prior to Re-initiation 
of Eculizumab 
(within 1 week prior) 
Q2W (±2 days) after 
Re-initiation  
Wk 2 through Wk 10 
Monthly (± 1 week) Visits, 
following schedule in Table 2 
Determined by the Date of 
First Intentional Eculizumab 
Discontinuation 
Patients Who 
Completed Monthly 
Study Visits For 
2 Years After the 
First Intentional 
eculizumab 
discontinuation 
 
 
Study Visits 
Visit 1R 
V2R – V6R (Wk 2 
through Wk 10 
[±2 days] after Re-
initiation) 
Monthly from Visit 7R 
Through Up to 2 Years After 
the First Intentional 
eculizumab discontinuation 
Visit 
EOS* 
/ET** 
TMA 
+UNS 
Visit 
^1TR 
^^2TR 
Dialysis 
X 
X 
X 
X 
X 
 
 
Blood Transfusion 
X 
X 
X 
X 
X 
 
 
Renal Transplantation 
X 
X 
X 
X 
X 
 
 
Blood/Urine Samples for Genetic and Biomarker Analyses 
Genetic Testsh 
 
 
 
 
 
 
 
Biomarker Testsi 
X 
X 
X 
X 
X 
X 
 
Blood samples for the following 
cRBC Hemolytic assayj 
X 
 
Only Every 6 Months Until 2 Years 
After the First Intentional 
Eculizumab Discontinuation (V10R, 
V16R, V22R) 
X 
X 
X 
 
Free C5j 
X 
 
X 
X 
X 
 
PKk 
X 
 
X 
X 
X 
 
Additional samplesl 
At the Discretion of the Investigator, additional/more frequent samples may be collected at Scheduled Study Visits/Unscheduled Visits 
Abbreviations: AE = adverse event; aHUS = atypical hemolytic uremic syndrome; cRBC = chicken red blood cell; ET = early termination; PK = 
pharmacokinetics; EOS = end-of-study; TMA = thrombotic microangiopathy; UNS = unscheduled visit 
* If a patient has completed all required study visits (for a total of 2 years from the time of the first intentional eculizumab discontinuation [Visit 1D]), the last 
Study Visit will be the end-of-study (EOS) visit, at which time the patient completes the study.   
** If a patient withdraws early from the study prior to completing all required monthly visits, an ET Visit will be performed. 
^  
If a patient experiences a TMA manifestation as defined in Section 7.3, the TMA visit (Visit 1TR) must be performed as soon as possible of symptom onset.  
Additional evaluation visits can be scheduled at the discretion of the investigator. 
^^ The TMA visit (Visit 2TR) must be performed within 2 weeks (±2 days) of Visit 1TR. 
+ Unscheduled visit and procedures will be performed at the Investigator’s discretion and results will be recorded in the eCRF. 
a Patients who re-initiate eculizumab treatment will have monthly study visits for 2 years after the time of the first intentional eculizumab discontinuation. Q2W 
visits are defined as every 2 weeks ie, every 14 days.  Monthly visits are defined as every 28 days ie, every 4 weeks. 
b Reasons for re-initiation will be systematically collected. 
 
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c Safety assessments (ie, vital signs, laboratory tests, assessments of TMA manifestations and associated supportive interventions, AEs, and concomitant 
medications/therapies) will be collected at the specified clinic visits prior to sample collection for biomarker tests.  For a summary of clinical laboratory tests 
see Appendix 1.  In addition, pregnancy-, lactation-, and follow-up-data on neonates for 3 months after delivery, especially when the neonate has experienced 
eculizumab EIU, will also be collected. 
d Height will be collected ONLY for pediatric patients. 
e Laboratory tests will include platelet count, serum albumin, serum LDH, serum creatinine, hemoglobin, haptoglobin, total bilirubin, full CBC, and urinalysis.  
Blood and urine for laboratory tests should be collected 5 to 90 minutes prior to administration of eculizumab.  Among patients receiving PE/PI or dialysis, 
blood and urine samples for laboratory tests will be collected prior to initiation of PE/PI or dialysis. 
f TMA manifestation assessments of aHUS including renal and extra-renal manifestations. 
g Associated supportive interventions including PE/PI, dialysis, blood transfusion, and renal transplantation. 
h Samples for genetic testing will be collected on Day 0 (Baseline) of the study however, may alternatively be collected at any other visit after Day 0 (Baseline) 
during the study.  A patient may be allowed to opt-out from providing a sample for genetic testing (eg, for religious reasons) and still continue to participate in 
the study. 
i Samples for biomarker analyses should be collected after safety assessments have been performed and prior to administration of eculizumab.  Among patients 
receiving PE/PI or dialysis, blood and urine samples will be collected 5 to 90 minutes prior to initiation of PE/PI or dialysis.  Unused samples will be stored for 
future analysis (see Section 14.1.3). 
j Blood samples for cRBC hemolytic assay and free C5 will be collected as specified until 2 years after the first intentional eculizumab discontinuation. 
k Blood samples for PK will be collected as specified until 2 years after the first intentional eculizumab discontinuation. 
l If a patient is experiencing a TMA manifestation additional blood samples may be collected at scheduled clinical visits/unscheduled visits, at the discretion of 
the Investigator. 
 
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17 November 2016 
Table 6: Schedule of Additional Assessments for Patients Receiving Eculizumab on a Reduced/Increased Dosing Regimen 
Assessments 
Patients Receiving Eculizumab on a 
Reduced/Increased Dosing Regimen 
At time of dose 
reduction/increase 
(- 2 days)a 
Monthlya,b 
(± 1Wk) 
Biomarker Tests 
X 
 
PK 
X 
X 
cRBC Hemolytic Assay 
X 
X 
Free C5 
X 
X 
Abbreviations: cRBC = chicken red blood cell; PK = pharmacokinetics 
a These assessments may occur during pre-scheduled monthly study visits or at unscheduled visits. This visit should be scheduled prior to the dose when 
possible; the visit window is within 2 days prior (-2D) to the reduction/increase. As with all other study visits, samples for assessments should be collected 5 to 
90 minutes prior to the administration of eculizumab. 
b For patients receiving eculizumab on a reduced/increased dosing regimen, monthly PK, cRBC, and free C5 will be drawn as long as the patient remains on a 
reduced/increased eculizumab dosing regimen.  
 
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7.3. 
Study Endpoints 
7.3.1. 
Primary endpoint: 
Rate of TMA manifestations, where TMA includes: 
1. Hematologic or renal events due to aHUS 
2. Extra-renal clinical signs and symptoms of aHUS 
3. Tissue biopsy demonstrating TMA due to aHUS 
7.3.2. 
Secondary endpoints: 
• Change in estimated Glomerular Filtration Rate (eGFR) over time using the chronic 
kidney disease-epidemiology (CKD-EPI) formula 
• Rate of TMA manifestations  
− while patient is on a labeled eculizumab dosing regimen 
− while patient is on a reduced/increased eculizumab dosing regimen 
(reduced/increased dose and or reduced/increased frequency) 
• Incidence of PE/PI  
7.3.3. 
Exploratory endpoints: 
• Changes in exploratory biomarker levels: 
− Biomarkers may include, but are not limited to: Ba, TNFR1, sVCAM-1, TM, 
D-dimer, markers of renal injury (eg, Cystatin C or other) and assessments of 
complement deposition on endothelial cells 
• Changes in PK (serum eculizumab concentration), pharmacodynamic (PD) (ie, cRBC 
hemolytic assay), free C5 
• Identification of novel genetic variants associated with aHUS  
• Development of progressive proteinuria 
• Incidence of change in dosing of eculizumab: 
− Re-initiation of eculizumab after intentional discontinuation 
− Start of labeled dosing after reduced/increased dosing 
• Incidence of transfusion 
• Patient-reported outcomes (FACIT-Fatigue [Appendix 2 and Appendix 3], EORTC 
QLQ-C30 [Appendix 4], and patient-reported aHUS symptoms [Appendix 5]) 
7.3.4. 
Safety endpoints: 
• Nature, severity, and relatedness to treatment of AEs (including serious adverse 
events [SAEs])  
 
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17 November 2016 
• laboratory tests (blood chemistry, hematology, and urinalysis) 
• other assessments (vital signs) 
7.3.5. 
Criteria for Site Reporting of Potential TMA Manifestations 
Data on all hematologic, renal, extra-renal clinical signs and symptoms, and tissue biopsy results 
will be collected whether the physician deems related or not to aHUS.  Information on etiology 
will be collected on clinical signs and symptoms deemed not related to aHUS will also be 
collected.  Only criteria considered related to aHUS will be reported as a potential TMA 
manifestation under the primary endpoint. 
For the purposes of reporting, a potential TMA manifestation is defined by at least one of the 
following criteria, although multiple criteria may be identified: 
1. Hematologic or renal events due to aHUS 
A. The occurrence of two or more of the following 3 hematologic or renal events, where 
the changes from baseline* (see baseline definition below) in laboratory values are 
confirmed by a 2nd consecutive value derived from local and/or central laboratories; if 
local laboratory values are to be used, they must be reported to the sponsor): 
• A decrease in platelet count by ≥25% below baseline and below the lower limit of 
normal (LLN) 
• Evidence of hemolysis, defined by at least one of the following: 
− An increase in serum LDH by ≥25% above baseline and above the upper limit of 
normal (ULN) 
− A decrease in haptoglobin below the LLN 
• A decline in kidney function that includes at least one of the following: 
− An increase in serum creatinine by ≥25% above baseline and above the ULN 
− An increase in proteinuria characterized by at least one of the following:  
- 
New onset of proteinuria: ≥2+ on urine dipstick or spot urine albumin to 
creatinine ratio ≥0.3 mg albumin/mg creatinine;  
- 
Worsening of existing proteinuria: ≥1.5 x increase in spot urine protein-to-
creatinine ratio from baseline 
- 
New onset of nephrotic-range proteinuria: spot urine protein-to-creatinine 
ratio from baseline of >3.5 mg protein/mg creatinine in adults and >3.0 mg 
protein/mg creatinine in children  
− Requirement for renal replacement therapy, including dialysis or kidney 
transplant 
B. The occurrence of two or more of the following 3 hematologic or renal events, that do 
not necessarily meet all the criteria listed under #1A above, but are due to aHUS in 
the opinion of the Investigator: 
• A clinically important decrease in platelet count 
 
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• Evidence of hemolysis, defined by at least one of the following: 
− A clinically important increase in serum LDH  
− A decrease in haptoglobin below the LLN 
• A clinically important decline in kidney function that includes at least one of the 
following: 
− A clinically important increase in serum creatinine  
− A clinically important increase in proteinuria, for example: new onset proteinuria, 
worsening of existing proteinuria, or new onset of nephrotic range-proteinuria 
− Requirement for renal replacement therapy, including dialysis or kidney 
transplant related to a TMA event 
*For reporting purposes, baseline is defined as follows:   
For a patient on ongoing eculizumab treatment without any treatment discontinuation, the 
baseline is the value at Day 0.  For a patient re-initiated on eculizumab treatment with at least 
one prior intentional discontinuation, the baseline for each on treatment period is the last 
laboratory value during the preceding intentional discontinuation period.  For a patient 
intentionally discontinued from eculizumab treatment, the baseline for each off treatment period 
is the last value during the preceding ongoing eculizumab treatment period. 
2. Extra-renal clinical signs and symptoms of aHUS 
The occurrence of extra-renal clinical signs and symptoms that in the opinion of the 
Investigator are due to aHUS AND at least one other test result that is consistent with the 
diagnosis of TMA related to aHUS OR excludes alternative etiologies of extra-renal signs 
and symptoms: 
• A single occurrence of any component of criterion #1A or #1B (hematologic or renal 
events due to aHUS) defined above (second/confirmatory value for laboratories not 
required) 
AND/OR 
• Relevant imaging study/studies demonstrating either tissue damage or excluding 
etiologies other than aHUS (eg, abdominal ultrasound that shows no gallstone in a 
setting of pancreatitis) 
AND/OR 
• Relevant laboratory data ruling out etiologies other than aHUS (eg, negative hepatitis 
serologies)  
3. Tissue biopsy demonstrating TMA due to aHUS 
7.3.6. 
Adjudication of Potential TMA Manifestations 
Events reported as meeting criteria (#1A, #1B, 2, or 3) listed in Section 7.3.5 above as well as 
potential events not indicated as meeting criteria will be adjudicated by an independent Endpoint 
Adjudication Committee as detailed in the Adjudication Committee Charter (Section 9.2.1). 
 
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17 November 2016 
7.4. 
Study Visit Procedures 
Treatment for aHUS will remain observational and at the discretion of the Treating Physician.  
At a given time, patients may be receiving ongoing eculizumab treatment, intentionally 
discontinued from eculizumab treatment, or re-initiated on eculizumab treatment.  Based on the 
eculizumab treatment status of the patient, assessments and procedures as specified in the 
following sections (Section 7.4.1 through Section 7.4.6) will be performed, as applicable.  
At visits where blood and urine samples are collected for biomarker analyses, safety assessments 
will be performed prior to sample collection for biomarker analyses.   
At visits where administration of eculizumab is scheduled, all sample collection should be 
performed 5 to 90 minutes prior to eculizumab infusion.  If the scheduled eculizumab dose falls 
within a study visit window, the study visit should be scheduled on the same day of the dose or 
within 48 hours prior to the dose, such that laboratory samples can be taken prior to the 
eculizumab dose. If the scheduled dose falls on the same day as the scheduled visit, blood 
samples are to be taken 5 to 90 minutes prior to administration.  It is preferred that the dose is 
scheduled on the same day as the visit, if possible. 
Due to blood volume limitations for lower body weight patients or due to other clinical factors 
per the Investigator’s discretion, blood samples will be collected based on the prioritization 
scheme described in the Laboratory Manual for this study.  In addition, detailed instructions for 
sample collection, preparation, and handling are provided in the Laboratory Manual.   
7.4.1. 
Core Procedures Performed At All Regularly Scheduled Study Visits and the 1st 
TMA Visits 
The following will be performed at all study visits for patients on ongoing treatment (V1 through 
V28/EOS/ET), with intentional discontinuation (V1D through V28D/EOS/ET), or re-initiation of 
eculizumab, (V1R through V28R/EOS/ET) as well as the 1st TMA visit (TMA 1T, 1TD, and 
1TR): (note: these procedures are not required for the TMA 2T, 2TD, or 2TR visits) 
• Core Procedure Safety assessments (Note:  All safety assessments and sample collection 
should be performed prior to eculizumab infusion) 
- Measure vital signs, including assessments of systolic and diastolic blood pressure 
(BP), temperature, respiration rate (RR), and heart rate (HR) 
- Height (to be done at baseline for all patients; at subsequent visits, only required 
for pediatric patients) and weight 
- Evaluate and record any new AEs or changes in AEs since the previous visit; at 
baseline, an initial assessment of AEs should occur 
- Record any new medications or changes to concomitant medications/therapies  
- Obtain blood and urine samples for the laboratory tests: Hematology, Blood 
Chemistry, and Urinalysis; see Appendix 1  
- Assessments of TMA manifestations including changes in specific laboratory 
parameters, renal and/or extra-renal signs and symptoms (see Section 7.3) 
 
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- For assessments of eculizumab treatment and associated supportive interventions, 
record the following: 
- eculizumab treatment regimen in treatment log 
- PE/PI 
- blood transfusion 
- dialysis 
- renal transplantation  
• Core Procedure Study-specific tests: After completing the safety assessments, the 
following study-specific tests will be performed:  
o Obtain blood and urine samples for biomarker analyses  
7.4.2. 
Visits for TMA Manifestation for all patients regardless of eculizumab treatment 
status: Visit 1T/1TD/1TR and Visit 2T/2TD/2TR  
The procedures at Visit 1T are the same as for Visit 1TD and Visit 1TR; however, the 
appropriate visit label and visit label abbreviations should be utilized to allow for clear data 
collection regarding the patient’s eculizumab treatment status (ie, “D” denotes intentional 
discontinuation, “R” denotes re-initiation following an intentional discontinuation, and for 
patients on ongoing treatment the additional letter is omitted).  Similarly, the procedures at 
Visit 2T are the same as for Visits 2TD and 2TR; however, the appropriate visit 
label/abbreviation should be used according to the patient’s eculizumab treatment status. 
In summary, 2 TMA manifestation visits will be performed.  The 1st TMA manifestation visit 
(Visit 1T or 1TD or 1TR) should be performed as soon as possible on recognition of signs and/or 
symptoms of TMA manifestation onset by the Investigator.  A 2nd TMA manifestation visit 
(Visit 2T or 2TD or 2TR) should be performed within 2 weeks of Visit 1T/1TD/1TR.  These 
visits may be combined with already scheduled study visits, if overlapping with the scheduled 
study visit window. 
Additional evaluation visits can be scheduled at the discretion of the Investigator. 
7.4.2.1. 
First (1st) TMA Visit - Upon Recognition of TMA Manifestation 
The 1st TMA manifestation visit (Visit 1T/1TD/1TR) should be performed as soon as possible on 
recognition of signs and/or symptoms of TMA manifestation onset by the Investigator.  
Additional evaluation visits can be scheduled at the discretion of the Investigator.   
In addition to the core procedures listed in Section 7.4.1, the following tests and procedures will 
be performed for Visit 1T/1TD/1TR (note: protocol-specific tests should always be collected 
after the safety assessments): 
• Obtain blood sample for the following: 
- Free C5 
- cRBC hemolytic assay 
- PK testing 
 
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7.4.2.2. 
Second (2nd) TMA Visit - Within 2 weeks [±2 days] of the 1st TMA Visit  
Note that the core procedures listed in Section 7.4.1 are not required at this visit.  
Only the following tests and procedures will be performed at the 2nd TMA visit (Visit 
2T/2TD/2TR): 
• Obtain blood and urine sample, as applicable, for the following: 
- Biomarker analyses 
- cRBC hemolytic assay 
- PK testing 
- Free C5 
7.4.3. 
Data Collection (During Year 1 and 2) for Patients Receiving Ongoing 
Eculizumab  
Following the Day 0 / Baseline Visit 1, patients will have study visits every two weeks (Q2W) 
until Week 10 (Visit 2 through Visit 6).  Beginning at Month 3 (Visit 7), patients will have 
monthly study visits for a total of 2 years (Visit 7-28), unless there is an intentional 
discontinuation in eculizumab treatment.  If there is an intentional discontinuation of eculizumab, 
the procedures in Section 7.4.5 should be followed. 
All Q2W and monthly visits (V1 through V28) for patients receiving ongoing Eculizumab 
Treatment will contain the core procedures listed in Section 7.4.1.   
7.4.3.1. 
Additional Data Collection on Day 0 (Baseline)/Visit 1 for Patients Receiving 
Ongoing Eculizumab Treatment 
In addition to the core procedures listed in Section 7.4.1, at the Day 0 (Baseline)/Visit 1, after 
obtaining the signed ICF, the following will be performed: 
• Review inclusion and exclusion criteria 
• Review medical history including aHUS diagnosis history.  Note: medical history data 
are only to be reported in the M11-001 aHUS Registry database and not through this 
study's database  
• Record demographics including age and sex of the patient 
• Complete physical examination will include assessments of the following organ/body 
systems: skin, head, ears, eyes, nose, throat, neck, lymph nodes, pulse, chest, heart, 
abdomen, extremities, musculoskeletal, and general neurologic examination 
After completing the safety assessments, the following will be performed:  
• Obtain blood sample for genetic testing (this sample may be collected at this visit or at 
any visit after Day 0 (Baseline)/Visit 1 during the study) 
• Obtain blood sample for the following: 
- Free C5 
- cRBC hemolysis assay 
 
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- PK testing  
• Patient-reported outcomes: 
- FACIT-Fatigue 
- EORTC QLQ-C30 
- aHUS symptoms 
7.4.3.2. 
Additional Data Collection at the Month 3 and Month 6 Visits for Patients 
Receiving Ongoing Eculizumab Treatment 
In addition to the core procedures listed in Section 7.4.1, the following will be performed at the 
Month 3 and Month 6 Visits. 
• Patient-reported outcomes: 
- FACIT-Fatigue 
- EORTC QLQ-C30 
- aHUS symptoms 
7.4.3.3. 
Additional data Collection at 6 Month Visits for Patients Receiving Ongoing 
Eculizumab Treatment 
In addition to the core procedures listed in Section 7.4.1, the following will be performed at 
6 Month Visits ie Visits V10/Month 6, V16/Month12, V22/Month 18, and 
V28/Month24/EOS/ET:  
• Obtain blood sample for the following (note: protocol-specific tests should always be 
collected after the safety assessments): 
- Free C5 
- cRBC hemolysis assay 
- PK testing  
7.4.3.4. 
Visit 28 (Month 24)/End-of-Study (EOS)/Early Termination (ET) Visit for 
Patients Receiving Ongoing Eculizumab Treatment: 
An End-of-Study (EOS) visit will be performed when a patient has completed all Study Visits 
(Visits 1 through 27) before a patient leaves the study or the study is terminated by the Sponsor 
or by a Regulatory Authority.  An Early Termination (ET) visit will be performed if a patient 
withdraws early during the study.  The procedures indicated in Section 7.4.3.3 should be 
performed.   
7.4.4. 
Additional Data Collection (During Year 1 and 2) for Patients Receiving 
Ongoing Eculizumab Treatment at a Reduced/Increased Dosing Regimen 
Evaluations for patients receiving ongoing eculizumab treatment at a reduced/increased dosing 
regimen will be the same as for patients receiving ongoing eculizumab treatment at a label-
recommended dosing regimen. 
 
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Tests, procedures, and assessments listed in Section 7.4.3, as appropriate, will be performed.  
7.4.4.1. 
Additional Data Collection at the Time of Eculizumab Dose/Dosing 
Reduction/Increase 
As specified earlier, at the discretion of the Treating Physician, patients may receive a 
reduced/increased eculizumab dose or reduced/increased dosing frequency (Section 7.1).  If a 
patient’s dose is reduced or increased after enrolling in the study, the following assessments and 
procedures will be performed on the visit day when the reduced/increased eculizumab dose 
regimen will be administered, or within 2 days prior, per the visit window.  These visits may 
occur during pre-scheduled monthly study visits or at unscheduled visits. 
The tests and procedures performed are: 
• Obtain blood and urine samples for biomarker analyses  
• Obtain blood sample for the following: 
− Free C5 
− cRBC hemolytic assay 
− PK testing 
7.4.4.2. 
Additional Data Collection Every Month for Patients on a Reduced/Increased 
Dosing Regimen  
In addition to the procedures for patients receiving a label-recommended dosing regimen, 
patients receiving eculizumab at a reduced/increased dosing regimen will require the following 
data to be collected on a monthly basis following the initial reduction/increase:  
• Obtain blood sample for the following: 
− Free C5 
− cRBC hemolytic assay 
− PK testing 
These monthly procedures are recommended to occur during pre-scheduled monthly study visits 
or may occur at unscheduled visits. 
7.4.5. 
Data Collection for Patients After Intentional Eculizumab Treatment 
Discontinuation and After any Subsequent Intentional Discontinuation(s) 
Following the first intentional eculizumab discontinuation, patients will have a study visit 
(Visit 1D) within 2 weeks after the last eculizumab infusion.  Patients will then have Q2W study 
visits until Week 10 (Visit 2D through Visit 6D).  Beginning at Month 3 (Visit 7D), patients will 
have monthly study visits for a total of 2 years (Visit 7D-28D).   
For any subsequent intentional eculizumab discontinuation, patients will follow the assessments 
as specified in Visit 1D, and Q2W study visits thereafter as specified in Visit 2D through 6D.  
Patients will have monthly visits beginning at Month 3 after the intentional eculizumab 
discontinuation for a total of 2 years from the time of the first intentional eculizumab 
 
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discontinuation.  The monthly visits will follow the schedule as determined by the date of the 
first intentional eculizumab discontinuation visit (Visit 1D). 
All Q2W and monthly visits for patients with a first or subsequent intentional eculizumab 
discontinuation will contain the core procedures listed in Section 7.4.1.  The following visits 
listed in Section 7.4.5.1 through 7.4.5.3 will require additional procedures as listed below 
7.4.5.1. 
Additional Data Collection at the Time of Intentional Discontinuation/Visit 1D 
(2 weeks [±2 days] After the Last Eculizumab Infusion) 
In addition to the core procedures listed in Section 7.4.1, the following will be performed (note: 
protocol-specific tests should always be collected after the safety assessments): 
• Obtain blood sample for the following: 
− Free C5 
− cRBC hemolytic assay 
− PK testing 
• Patient-reported outcomes: 
- FACIT-Fatigue 
- EORTC QLQ-C30 
- aHUS symptoms 
7.4.5.2. 
Additional Data Collection at V2D/Week 2, 3D/Week 4, and V7D/Month 3 for 
Patients After Intentional Eculizumab Treatment Discontinuation 
In addition to the core procedures listed in Section 7.4.1, the following will be performed (note: 
protocol-specific tests should always be collected after the safety assessments): 
• Obtain blood sample for the following: 
− Free C5 
− cRBC hemolytic assay 
− PK testing 
7.4.5.3. 
Additional Data Collection at V7D/Month 3 and V10D/Month 6 for Patients 
After Intentional Eculizumab Treatment Discontinuation 
In addition to the core procedures listed in Section 7.4.1, the following PRO will be collected. 
• Patient-reported outcomes: 
- FACIT-Fatigue 
- EORTC QLQ-C30 
- aHUS symptoms 
 
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7.4.5.4. 
Visit 28D/Month 24/End-of-Study (EOS)/Early Termination (ET) Visit for 
Patients After Intentional Eculizumab Treatment Discontinuation 
An EOS visit will be performed when a patient has completed all Study Visits (Visits 1D through 
27D) before a patient leaves the study or the study is terminated by the Sponsor or by a 
Regulatory Authority.  An ET visit will be performed if a patient withdraws early during the 
study.   
In addition to the core procedures listed in Section 7.4.1, the following will be performed (note: 
protocol-specific tests should always be collected after the safety assessments): 
• Obtain blood sample for the following: 
− Free C5 
− cRBC hemolytic assay 
− PK testing 
7.4.6. 
Data Collection for Patients who Re-initiate Eculizumab Treatment After an 
Intentional Discontinuation:  Re-initiation After the First Intentional 
Eculizumab Discontinuation and Any Subsequent Re-initiation(s) 
Following an intentional eculizumab discontinuation, patients who re-initiate eculizumab 
treatment will have a study visit (Visit 1R) at the time of re-initiation i.e. within 1 week prior to 
re-initiation.  Patients will then have Q2W study visits until Week 10 (Visit 2R through Visit 
6R).  Beginning at Month 3 (Visit 7R), patients will have monthly study visits for a total of 
2 years (Visit 7R-EOS/ET) from the first intentional eculizumab discontinuation.   
All Q2W and monthly visits for patients who re-initiate eculizumab will contain the core 
procedures listed in Section 7.4.1.  The following visits listed in Section 7.4.6.1 through 7.4.6.3 
will require additional procedures as listed below. 
7.4.6.1. 
Additional Procedures at the Time of Eculizumab Re-initiation/Visit 1R (1 Week 
Prior to Re-initiation [±2 days]) 
In addition to the core procedures listed in Section 7.4.1, the following will be performed (note: 
protocol-specific tests should always be collected after the safety assessments): 
• Obtain blood sample for the following: 
− Free C5 
− cRBC hemolytic assay 
− PK testing  
7.4.6.2. 
Additional data Collection at 6 Month Visits: Visits V10R/Month 6, 
V16R/Month 12, V22R/Month 18 for Patients who Re-initiate Eculizumab 
Treatment After an Intentional Discontinuation 
In addition to the core procedures listed in Section 7.4.1, the following will be performed at 
6 Month Visits ie, Visits V10R/Month 6, M16R/Month 12, V22R/Month 18 (note: protocol-
specific tests should always be collected after the safety assessments):  
 
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• Obtain blood sample for the following: 
− Free C5 
− cRBC hemolysis assay 
− PK testing  
7.4.6.3. 
End-of-Study (EOS)/Early Termination (ET) Visit for Patients who Re-initiate 
Eculizumab Treatment After an Intentional Discontinuation 
An EOS visit will be performed when a patient has completed all required study visits (for a total 
of 2 years from the time of the first intentional eculizumab discontinuation visit [Visit 1D]) or 
the study is terminated by the Sponsor or by a Regulatory Authority.  An ET visit will be 
performed if a patient withdraws early during the study.   
In addition to the core procedures listed in Section 7.4.1, the following will be performed (note: 
protocol-specific tests should always be collected after the safety assessments): 
• Obtain blood sample for the following: 
− Free C5 
− cRBC hemolysis assay 
− PK testing  
7.4.7. 
Visits at the Discretion of the Investigator 
If a patient is experiencing a TMA manifestation additional blood samples may be collected at 
scheduled clinical visits/unscheduled visits, at the discretion of the Investigator. 
7.4.8. 
Unscheduled Visits  
Additional (Unscheduled) visits outside the specified visits are permitted at the discretion of the 
Investigator.  Procedures, tests, and assessments will be performed at the discretion of the 
Investigator.  If an Unscheduled Visit is performed, any tests, procedures, or assessments 
performed at the Unscheduled Visits must be recorded on the eCRFs. 
7.4.9. 
Missing Visits  
Patients who fail to return for a scheduled visit must be contacted by the site study staff to 
determine the reason for missing the appointment.  For patients who are being treated with 
eculizumab and who miss a dose, the Investigator may contact the Medical Monitor to discuss 
the status and future treatment of these patients.  Patients should be strongly encouraged to return 
to the study site for evaluation if a TMA manifestation or an AE is suspected to have occurred.  
As it is vital to obtain information on a patient’s missing visit to assure the missing appointment 
was not due to a TMA manifestation or an AE, every effort must be made to follow-up with the 
patient.  Follow-up due diligence documentation will consist of 3 phone calls followed by 
1 registered letter to the patient’s last known address, and documented in both the source 
documents and the eCRF. 
 
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In cases where a scheduled study visit at the site cannot occur, data may be collected via 
telephone, where possible, or remotely, as permissible by and in accordance with all applicable 
regulatory requirements.
 
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8. 
SELECTION AND WITHDRAWAL OF PATIENTS 
8.1. 
Patient Participation 
Any M11-001 aHUS Registry patient currently on eculizumab treatment and meeting all the 
eligibility criteria will receive information from the Investigator regarding participation and will 
sign a consent form prior to their enrollment in this study.  Patients must remain enrolled in the 
M11-001 aHUS Registry in order to remain eligible to participate in the current study.  Any 
patient discontinuing from the M11-001 aHUS Registry must discontinue from the current study.  
Day 0 (Baseline) assessments of a patient will commence only after patient’s consent is 
documented. 
8.2. 
Inclusion Criteria 
Patients of any age, including minors, enrolled in the M11-001 aHUS Registry should meet all of 
the inclusion criteria below to be eligible for enrollment in the study: 
1. Currently receiving eculizumab treatment in the M11-001 aHUS Registry  
2. Two normal platelet counts (eg, >150,000/μL) at least 4 weeks apart while on eculizumab 
within the past 12 months 
3. Two normal LDH levels (eg, <1.5 x ULN) at least 4 weeks apart while on eculizumab 
within the past 12 months 
4. Willing, committed, and able to return for ALL clinic visits and complete all study-
related procedures 
5. Patient or patient’s parent/legal guardian must be willing and able to give written 
informed consent.  Patient (if minor) must be willing to give written informed assent (if 
applicable as determined by the central Institutional Review Boards/Independent Ethics 
Committees [IRB/IEC]). 
8.3. 
Exclusion Criteria 
Patients enrolled in the M11-001 aHUS Registry Study who meet any 1 of the following criteria 
will be excluded from the study:  
1. Any prior intentional discontinuation of eculizumab treatment  
2. On chronic dialysis (defined as ≥3 months on dialysis) 
3. Currently participating in another complement inhibitor trial 
4. With life expectancy of <6 months 
5. Patient or patient's parent/legal guardian unable to give written informed consent.  Patient 
(if minor) unable to give written informed assent (if applicable as determined by the 
central Institutional Review Boards/Independent Ethics Committees [IRB/IEC]). 
 
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8.4. 
Patient Withdrawal Criteria 
8.4.1. 
Withdrawal of Patients From the Study 
Patients may decide to withdraw participation in the study (by notifying the Investigator verbally 
or in writing) at any time without penalty and without affecting future medical care.  Every effort 
should be made to ensure patients are willing to comply with study participation prior to 
conducting the Day 0 (Baseline) procedures. 
Patients may decide to withdraw participation in the study and can still continue to participate in 
the M11-001 aHUS Registry. However, any patient discontinuing from the M11-001 aHUS 
Registry must discontinue from the current study. 
Investigators may choose to withdraw a patient because of an AE or because of conditions or 
illnesses that preclude compliance with the protocol from the standpoint of the patient’s safety or 
well-being (safety, behavioral or administrative reasons).   
8.4.2. 
Handling of Withdrawals 
When a patient withdraws or is withdrawn from the study, the Investigator shall record the 
withdrawal reason(s).  Whenever possible, all patients who prematurely withdraw from the study 
will undergo all assessments at the ET visit for safety as per the Schedule of Assessments 
(Table 3, Table 4, and Table 5).   
If a patient is withdrawn due to an AE, the event will be followed until it is resolved or in the 
opinion of the Investigator the patient is determined to be medically stable.  Every effort will be 
made to undertake protocol-specified safety follow-up procedures. 
Patients who fail to return for final assessments will be contacted by the study site staff in an 
attempt to request them to comply with the protocol.  As it is vital to obtain follow-up data on 
any patient withdrawn because of an AE or SAE, follow-up due diligence documentation will 
consist of 3 phone calls followed by 1 registered letter to the patient’s last known address.  Every 
effort must be made to undertake protocol-specified safety follow-up procedures. 
8.4.3. 
Sponsor’s Termination of Study 
Alexion may terminate the study at any time for any reason including, for example, clinical or 
administrative reasons. 
8.4.4. 
End of Study Definition 
The end of study is defined as the last visit completed by the last patient. 
 
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9. 
STUDY ASSESSMENTS 
9.1. 
Safety Parameters 
9.1.1. 
Vital Signs 
Vital signs will be measured at every visit and will include assessments of systolic and diastolic 
blood pressure (BP), temperature, respiration rate (RR) and heart rate (HR).  Vital signs will be 
obtained after the patient has been supine or seated for at least 5 minutes.  Ideally, each patient’s 
BP should be measured using the same arm.  Systolic and diastolic BPs will be documented in 
mmHg.  Temperature will be obtained in degrees Celsius or Fahrenheit.  HR will be documented 
in beats per minute. 
9.1.2. 
Physical Examination 
A complete physical examination will be performed only at the Baseline visit. The complete 
physical examination will include assessments of the following organ/body systems: skin, head, 
ears, eyes, nose, throat, neck, lymph nodes, pulse, chest, heart, abdomen, extremities, 
musculoskeletal, and general neurologic examination.  
9.1.3. 
Laboratory Tests  
Blood and urine for laboratory tests should be collected 5 to 90 minutes prior to administration of 
eculizumab.  For patients on eculizumab, if the scheduled dose falls within a study visit window, 
the study visit should be scheduled on the same day of the dose or within 48 hours prior to the 
dose, such that laboratory samples can be taken prior to the eculizumab dose. If the scheduled 
dose falls on the same day as the scheduled visit, blood samples are to be taken 5 to 90 minutes 
prior to administration.  It is preferred that the dose is scheduled on the same day as the visit, if 
possible.  
 
 
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9.2. 
Assessments for TMA Manifestations 
Assessments for TMA manifestations will be performed at every visit.  Changes in specific 
laboratory parameters (platelet count, serum creatinine, serum LDH, haptoglobin, and urinalysis) 
along with renal and extra-renal signs and symptoms as defined in Section 7.3 will be assessed at 
these visits, and can be derived from local and/or central laboratories.  Data will be collected 
regardless of relationship to TMA in the opinion of the Investigator. 
9.2.1. 
Endpoint Adjudication Committee  
Data supporting the primary endpoint of TMA manifestations, blinded to eculizumab treatment 
status, will be reviewed by the Endpoint Adjudication Committee on a regular basis for purposes 
of adjudicating the primary endpoint.  A description of the data included in the review, 
composition of the committee, and other relevant information will be detailed in the Endpoint 
Adjudication Committee Charter. 
9.3. 
Assessments of Eculizumab Treatment and Associated Supportive 
Interventions 
For assessment of eculizumab treatment, the following information will be collected at every 
visit in the eculizumab treatment log: 
• eculizumab dose administered  
• eculizumab dosing frequency 
• any changes in eculizumab dosing regimen (dose and/or frequency) 
 
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− reason for change in dosing regimen  
• whether eculizumab was discontinued 
− reason for intentional eculizumab treatment discontinuation  
• whether eculizumab was re-initiated 
− reason for re-initiation 
For the assessment of associated supportive interventions, the use of treatments such as PE/PI, 
dialysis, blood transfusions, and renal transplantation will be collected at every visit during the 
study.   
9.4. 
Contraception 
All patients entering into the study are treated with Soliris per recommendations of local 
marketing authorization approval. Although there have been no adequate and well-controlled 
studies of Soliris in pregnant women, Soliris is expected to cross the placenta. Local Soliris 
labeling may recommend contraception during treatment for women of childbearing potential.  
For example, the European SmPC recommends for women of childbearing potential to use 
effective contraception during treatment and up to 5 months after treatment with Soliris. 
Investigators must provide recommendations on contraception, if necessary, as per local label. 
9.5. 
Adverse Events 
9.5.1. 
Detection of Adverse Events 
The Investigator is responsible for detecting, assessing, documenting and reporting of all 
Adverse Events (AEs). 
AEs reported by the patient and/or parent or legal guardian and/or identified in response to an 
open-ended question from study personnel or revealed by observation, physical examination, or 
other study procedures must be collected and recorded. 
9.5.2. 
Definition of an Adverse Event 
Adverse event means any untoward medical occurrence in a patient or clinical study patient 
administered a medicinal product and which does not necessarily have a causal relationship with 
this treatment. 
All observed or volunteered AEs regardless of causal relationship will be recorded and reported 
as described in the sections below. 
For all AEs the Investigator must obtain adequate information for the following: (1) determine 
the outcome of the AE; (2) determine if the event meets criteria for a serious adverse event 
(SAE); (3) assess the severity of the AE, and (4) determine the causality of the AE.  For AEs 
with a causal relationship to the treatment, the Investigator must follow-up on the outcome of the 
event until the event or sequelae either resolve or stabilize. 
For each AE, the Investigator will be responsible for assessing seriousness, severity, and 
relationship of the AE to product. 
 
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An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory 
finding, for example), symptom, or disease temporally associated with the use of a medicinal 
product, whether or not considered related to the medicinal product. 
Exacerbation of a chronic or intermittent pre-existing condition including either an increase in 
frequency and/or intensity of the condition, and abnormal laboratory findings that are considered 
to be of clinical significance are all to be considered AEs. 
The definition of AE covers also medication errors and uses outside what is foreseen in the 
protocol, including misuse and abuse of the product. 
Situations where an untoward medical occurrence did not occur (social and/or convenience 
admission to a hospital), and 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 are not AEs. 
9.5.2.1. 
Abnormal Test Finding 
Abnormal test findings may be considered AEs or SAEs; however, Investigators are strongly 
encouraged to report the diagnosis, sign or symptom instead of just the abnormal result.  The 
criteria for an abnormal test finding being classified as an AE or SAE are as follows: 
• Test result is associated with a sign or symptom; 
• Test result requires additional diagnostic testing; 
• Test result requires a medical or surgical intervention; 
• Test result leads to a change in study dosing outside of the protocol defined dosing or 
discontinuation from the study;  
• Test result requires significant additional treatment (ie, addition of new medication, 
significant increase in dose of current medication). 
9.5.2.2. 
Serious Adverse Event and SAE Criteria 
Any AE that fulfills any 1 of the criteria listed below must be recorded as an SAE. An SAE 
(experience) or reaction is described as any untoward medical occurrence that at any dose: 
• Results in death 
• Is life-threatening 
NOTE: The term "life-threatening" in the definition of "serious" refers to an event in which the 
patient was at risk of death at the time of the event; it does not refer to an event which 
hypothetically might have caused death if it were more severe. 
• Requires in-patient hospitalization or prolongation of existing hospitalization 
• Results in persistent or significant disability/incapacity 
• Is a congenital anomaly/birth defect 
• Important medical event 
Medical and scientific judgment should be exercised in deciding whether expedited reporting is 
appropriate in other situations, such as important medical events that may not be immediately 
 
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life-threatening or result in death or hospitalization but may jeopardize the patient or may require 
intervention to prevent one of the other outcomes listed in the definition above.  These should 
also usually be considered serious.  Examples of such events are 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. 
9.5.2.3. 
Hospitalization 
AEs that are associated with hospitalization or prolongation of hospitalization are considered 
SAEs.  All admissions to a health care facility meet this criteria, even if less than 24 hours. 
Criteria for seriousness are also met if transfer within the hospital is done to receive more intense 
medical/surgical care (eg, medical floor to the intensive care unit [ICU]).   
Hospitalization does not include the following: 
• Rehabilitation facility 
• Hospice facility 
• Nursing facility 
• Emergency Room 
• Same day surgery 
Hospitalization or prolongation of hospitalization not associated with an AE is not an SAE, 
examples include: 
• Admission for a pre-existing condition not associated with either a new AE or with 
worsening of a pre-existing AE 
• Protocol-specified admission 
• Pre-planned admission 
9.5.2.4. 
Procedures 
Elective procedures that were pre-planned prior to the time that written ICF was obtained are not 
AEs. Any complication or worsening of a pre-existing condition leading to the procedure must 
be considered an AE. In addition, any AE that could occur as an outcome of the planned 
procedure should be considered as an AE. 
Diagnostic and therapeutic procedures (invasive and non-invasive) such as surgery or 
angiography should not be reported as an AE or SAE.  However, the medical condition or the 
diagnosis that was responsible for the procedure should be recorded.  The procedure should be 
recorded in the narrative as treatment for the AE or SAE (eg, laparoscopic cholecystectomy is 
the procedure or treatment for an SAE of necrotic gall bladder). 
9.5.2.5. 
Events of Interest 
Events of Interest (EOI) will be identified by the Drug Safety Physician and if applicable also by 
the Clinical Trial Team Physician during the evaluation of safety data for the Clinical Study 
Report.  Significant AEs of particular clinical importance, other than SAEs and those AEs 
 
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leading to discontinuation of the patient from the study will be classified as other AEs.  For each 
EOI, a narrative may be written and included in the Clinical Study Report. 
9.5.2.6. 
Severity Assessment  
AE severity will be rated by the Investigator as mild, moderate, or severe using the following 
criteria: 
• Mild: events require minimal or no treatment and do not interfere with the patient’s 
daily activities. 
• Moderate: events result in a low level of inconvenience or concerns with the 
therapeutic measures. Moderate events may cause some interference with 
functioning. 
• Severe: events interrupt a patient’s usual daily activity and may require systemic drug 
therapy or other treatment. Severe events are usually incapacitating. 
If an AE changes in severity over the duration of the event, the maximum (ie, worst) severity 
should be reported. 
Severity and seriousness must be differentiated.  Severity describes the intensity of an AE, while 
the term seriousness refers to an AE that has met the criteria for an SAE. 
9.5.2.7. 
Causality Assessment  
An Investigator causality assessment (Unrelated, Unlikely, Possible, Probable, or Definite) must 
be provided for all AEs (both serious and non-serious).  This assessment must be recorded in the 
eCRF and any additional SAE forms as appropriate.  The definitions for the causality 
assessments appear below. 
• Not related (unrelated): This relationship suggests that there is no association between 
eculizumab and the reported event. 
• Unlikely related: This relationship suggests that the clinical picture is highly 
consistent with a cause other than eculizumab, but attribution cannot be made in 
absolute certainty and a relationship between eculizumab and AE cannot be excluded 
with complete confidence. 
• Possibly related: This relationship suggests that treatment with eculizumab may have 
caused or contributed to the AE, i.e. the event follows a reasonable temporal sequence 
from the time of drug administration and/or follows a known response pattern to 
eculizumab, but could also have been produced by other factors. 
• Probably related: This relationship suggests that a reasonable temporal sequence of 
the event with eculizumab administration exists and the likely association of the event 
with eculizumab. This will be based upon the known pharmacological action of 
eculizumab, known or previously reported adverse reactions to eculizumab or class of 
drugs, or judgment based on eculizumab’s clinical experience. 
• Definitely related: Temporal relationship to eculizumab, other conditions (concurrent 
illness, concurrent medication reaction, or progression/expression of disease state) do 
 
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not appear to explain event, corresponds with the known pharmaceutical profile, 
improvement on discontinuation, re-appearance on re-challenge. 
9.5.2.8. 
Exposure during Pregnancy and Lactation 
Pregnancy data will be collected during this study for all patients. 
For all Alexion products, both in development or post approval, exposure during pregnancy must 
be recorded and followed. Exposure during pregnancy also called exposure in-utero (EIU) can be 
the result of either maternal exposure or transmission of drug product via semen following 
paternal exposure.   
If a patient within this study or a patient’s partner becomes or is found pregnant while treated or 
exposed to eculizumab, the Investigator must submit a pregnancy form to Alexion via the same 
method as SAE reporting. Pharmacovigilance will supply the Investigator with a copy of a 
“Pregnancy Reporting and Outcome Form / Breast Feeding”. Pharmacovigilance must be 
notified.  
Exposure of an infant to an Alexion product during breastfeeding would need to be reported in 
the “Pregnancy Reporting and Outcome Form / Breast Feeding”, and any AEs an infant may 
experience following breastfeeding needs to be reported to Alexion Pharmacovigilance or its 
delegate. 
The patient or a female partner should be followed until the outcome of the pregnancy is known 
(spontaneous miscarriage, elective termination, normal birth or congenital abnormality), even if 
the patient discontinued treatment with eculizumab or withdraws from the study. When the 
outcome of the pregnancy becomes known the form should be completed and returned to 
Alexion Pharmacovigilance or its delegate. If additional follow-up is required, the Investigator 
will be requested to provide the information. 
Pregnancy in itself is not regarded as an AE unless there is a suspicion that eculizumab may have 
interfered with the effectiveness of a contraceptive medication. However, complications of 
pregnancy and abnormal outcomes of pregnancy are AEs and many may meet criteria for a SAE. 
Complications of pregnancy and abnormal outcomes of pregnancy such as ectopic pregnancy, 
spontaneous abortion, intrauterine fetal demise, neonatal death, or congenital anomaly would 
meet criteria of a SAE and thus, should be reported as an SAE. Elective abortions without 
complications should not be handled as AEs.  Pregnancy-, lactation-, and follow-up-data on 
neonates for 3 months after delivery, especially when the neonate has experienced eculizumab 
EIU, will be collected. 
9.5.2.9. 
Withdrawal due to an AE  
Withdrawal from the study due to an AE or SAE must be clearly differentiated from withdrawal 
due to other reasons.   
9.5.2.10. Reporting Period 
For SAEs, the reporting period to Alexion Pharmacovigilance or its delegate begins following 
the patient’s signing of the ICF (providing consent to participate in the study) and continues 
through the patient’s EOS/ET Visit.   
 
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For non-serious AEs, the reporting period begins following the patient’s signing of the ICF 
(providing consent to participate in the study) and continues through the last visit (EOS/ET).   
All medical events that occurred prior to patient’s signing of the ICF and do not meet the SAE 
criteria are considered as medical history and do not need to be reported as AEs (pre-existing 
conditions). 
9.5.2.11. Reporting Requirements for AEs 
All AEs must be assessed by the Investigator to determine if they meet criteria for an SAE. If 
criteria are met for an SAE the event must be reported to Alexion Pharmacovigilance or its 
delegate as per requirements in Section 9.5.2.14. 
9.5.2.12. Reporting Requirements for Non-serious AEs 
All non-serious AEs must be recorded in the eCRF upon awareness. 
9.5.2.13. Reporting Requirements for SAEs 
All AEs must be assessed by the Investigator to determine if they meet criteria for an SAE. For 
SAEs, Alexion Pharmacovigilance or its delegate must be notified immediately or within 
24 hours of the Investigator and/or study site staff becoming aware of the event, regardless of the 
presumed relationship to eculizumab or to study procedure.  If the event meets criteria for a fatal 
or life threatening SAE criteria, the Investigator should notify Alexion Pharmacovigilance or its 
delegate immediately.  These reporting timelines need to be followed for all initial SAE cases 
and follow-up versions to the initial case. 
The Investigator must verify the accuracy of the information recorded on the SAE pages of the 
eCRF with the corresponding source documents, and submit the SAE electronically via the 
Safety Gateway. If the eCRF is not available, the Investigator must complete, sign, and date 
paper SAE pages and send a copy via Email or fax to contact information provided below: 
Email:   
 
Fax:  
 
When further information becomes available, the SAE Form should be updated with the new 
information and reported immediately via the same contact information. 
Additional follow-up information, if required or available, should be entered into the eCRF or 
sent to the Sponsor or designee within 24 hours of the Investigator or study site staff becoming 
aware of this additional information.  These reporting timelines should be followed for all initial 
and follow-up SAEs. 
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) 
• Outcome of the SAE(s) 
• Medical records and laboratory/diagnostic information 
If a patient experiences a SAE with an outcome of death: 
 
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• The SAE resulting in death should have an outcome documented as death/fatal with 
an end date being the date of death. 
• If the patient had additional AE/SAEs that were ongoing at the time of death, these 
events would be documented as ongoing with no end date. 
• Only one event should have an outcome of death/fatal unless an autopsy report or 
investigator states otherwise. 
9.5.2.14. Sponsor Reporting Requirements 
The Sponsor or legal representative is responsible for notifying the relevant regulatory 
authorities of SAEs meeting the reporting criteria as per regional and local regulations.   
9.5.2.15. Investigator Reporting Requirements 
The investigator must fulfill all local regulatory obligations required for study investigators. It is 
the PI’s responsibility to notify the IRB or IEC of all SAEs that occur at his or her site. 
Investigators will also be notified of all unexpected, serious, drug-related events (7/15 Day 
Safety Reports) that occur during the clinical study.  Each site is responsible for notifying its IRB 
or IEC of these additional SAEs. 
9.6. 
Pharmacokinetic/Pharmacodynamic Assessments 
Blood samples for PK (plasma eculizumab concentrations)/PD (cRBC hemolysis assay) 
assessments will be collected as specified in Table 3 through Table 6 in Section 7.2.  Samples for 
free C5 will also be collected as specified in the Schedule of Assessments tables (Table 3 
through Table 6) in Section 7.2. 
9.7. 
Genetic and Biomarker Assessments 
Blood and urine samples for biomarker tests will be collected at specified time points (See 
Schedule of Assessments tables [Table 3 through Table 6] in Section 7.2).  For genetic testing, 
blood samples collected on Day 0 (Baseline/Visit 1) or any visit thereafter will be used.  The 
genetic testing kit will also contain samples to be collected for CFH and CFI antibody testing, to 
be analyzed by the designated genetic lab. Genetic mutations of known clinical relevance in 
aHUS may be communicated to the patient or patient’s guardian by the Investigator together 
with appropriate genetic counseling.  Genetic mutations of unknown significance (novel 
variants) identified through exploratory analysis will not be communicated to patients or their 
Investigator. 
9.8. 
Patient Related Outcomes Assessments 
Patient related outcomes including the Functional Assessment of Chronic Illness Therapy 
(FACIT)-Fatigue instrument (Appendix 2 and Appendix 3), European Organization for Research 
and Treatment of Cancer quality of life questionnaire (EORTC QLQ-C30) (Appendix 4), and 
pre-specified patient-reported aHUS symptoms (Appendix 5) will be assessed as specified in 
Table 3 and Table 4. 
 
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10. 
SAMPLE SIZE AND STATISTICAL METHODS 
10.1. 
Sample Size Estimation 
The primary outcome of the study is TMA manifestation as a dichotomous variable.  Preliminary 
data from the aHUS Registry shows about 20% of patients reporting discontinuation of 
eculizumab treatment.  Additionally, longitudinal data on file at Alexion shows a difference of 
15% in proportion of patients with TMA manifestations between patients who discontinue 
treatment compared to those who remain on treatment.  The estimated sample size needed to 
detect a difference of 15% in TMA manifestations with power=80% in the proposed study is 300 
patients (60 patients with eculizumab treatment discontinuation and 240 patients who continue 
ongoing treatment).  Assuming a 10% loss to follow-up, the estimated sample size needed for the 
study is 330 patients. 
10.2. 
Statistical Methods 
10.2.1. 
Analysis Sets 
The full analysis set (FAS) is defined as all aHUS patients who signed an informed consent for 
this study (ECU-aHUS-403).  The per protocol set includes all enrolled patients who did not 
have any major protocol deviations deemed to potentially influence the primary analysis 
endpoint.  This set will be determined prior to database lock.  The safety set is defined the same 
way as the FAS and consists of all patients who signed an informed consent for this study. 
10.2.2. 
General Considerations 
Study ECU-aHUS-403 aims to assess TMA manifestations in patients with aHUS with or 
without ongoing eculizumab treatment.  Treatment for aHUS is non-randomized and is at the 
discretion of the Treating Physician.  Hypothesis testing will be done using a two-sided α=0.05 
Type 1 error rate, unless otherwise stated.  For continuous variables, descriptive statistics 
(number of patients with non-missing values (N), mean, standard deviation [SD], median, 
minimum, and maximum) will be provided.  For categorical variables, patient counts and 
percentages will be presented.  The percentages will be calculated based on the total number of 
patients in the FAS or the safety set.  The statistical analysis plan will define specific analyses 
that will be repeated on the per protocol set as sensitivity analyses.  Analyses will be conducted 
using SAS Version 9.2 or higher. 
Eculizumab Treatment Status: 
All patients at their entry into the study will be receiving eculizumab treatment, dosed either on-
label or at a reduced/increased dosing regimen, with no prior intentional discontinuation(s) of 
eculizumab treatment.  Once enrolled in the study, patients are allowed to discontinue 
eculizumab treatment or re-initiate eculizumab treatment at the discretion of the Treating 
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Eculizumab treatment status will be classified for analytical purposes as follows: 
• On-eculizumab treatment: from the date of enrollment through three weeks after last 
infusion of eculizumab or until the patient withdraws from the study, or until the 
patient completes the study, whichever occurs first.   
• Off-eculizumab treatment: from three weeks after the last infusion of eculizumab 
and continue until the patient re-initiates eculizumab treatment or until the patient 
withdraws from the study, or until the patient completes the study, whichever occurs 
first.  
For both the above categories, the time will accrue as specified until the patient changes 
treatment status category, or until the patient is discontinued from the study, or until the patient 
completes the study. 
10.2.3. 
Patient Disposition 
For patients who withdraw from the study, the reason for study discontinuation will be 
summarized.  For patients who intentionally discontinued eculizumab treatment, reasons for 
intentional discontinuation will be summarized as recorded in the clinical database.  A by-patient 
disposition status listing will be provided for all enrolled patients with the following information: 
patient ID, date of signed informed consent, date of the intentional eculizumab discontinuation, 
reason for intentional eculizumab treatment discontinuation, date of study withdrawal, and the 
reason for study withdrawal. 
10.2.4. 
Patient Characteristics 
All demographic and baseline characteristics information will be summarized using frequency 
counts and percentages for categorical variables, and summary statistic for continuous variables. 
10.2.5. 
Concomitant Therapy  
Concomitant medications will be summarized with counts and percentages for each medication 
and Anatomic Therapeutic Chemical (ATC) level 3 class.  Patients will be reported just once for 
a particular drug or ATC class.  Additionally, concomitant medications will be presented in a 
listing. 
10.2.6. 
Treatment Compliance  
As previously stated, all patients enrolled in this study will be patients on eculizumab treatment 
at the time of entry into the study.  Patients are allowed to discontinue eculizumab treatment as 
well as re-initiate eculizumab treatment at the discretion of the Investigator.  It is expected that 
some patients may also be receiving eculizumab following a reduced/increased dosing regimen 
(reduced/increased dose and or reduced/increased frequency).  Analyses to evaluate how this 
affects the primary endpoint will be performed. 
10.2.7. 
Primary Endpoint Analyses 
Primary analyses will focus on comparison of rates (ie, adjusted appropriately for exposure 
periods) of new TMA disease manifestations between time on eculizumab treatment and time off 
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In this context in which treatment exposure is a time varying confounder in that it affects the 
occurrence of a TMA disease manifestation and can subsequently be affected by a TMA disease 
manifestation, marginal structural models will be used.  Marginal structural models estimation 
employs inverse-probability of treatment weighting (IPTW) and robust estimation methods.  The 
goal of IPTW estimation is to obtain coefficients to create weights that will redistribute the 
population so that, in this case, treatment exposure is not temporally confounded (ie, creating a 
pseudo-population in which treatment exposure is no longer temporally confounded).  The 
factors that may confound the association are considered in a treatment model (or weight model), 
which is used as part of the IPTW estimation methodology to obtain estimates of, again in this 
context, difference in incidence rates between time on and off treatment. 
Differences between incidence rates of TMA disease manifestations will be estimated using 
negative binomial regression.  A generalized linear negative-binomial model for rates consists of 
following: 
tj the length of observation for patient j (expressed in days, months or years) 
Yj the count for patient j during tj  
xj the vector of baseline covariates including study treatment for patient j 
µj the mean of the negative binomial distribution of Yj 
The conditional mean for the distribution of the rate µj/tj for patient j given his/her baseline 
covariates xj, is modeled by the following equation:  
log (μj/tj)=x’jθ,    ie, log(μj)=x’jθ+log(tj),  where θ 
 is the vector of unknown fixed model 
parameters for baseline covariates including study treatment. 
Within the negative binomial regression model, the null hypothesis of no treatment effect 
(θtreatment =0) is tested against the alternative hypothesis (θtreatment <0) by a one-sided Wald-type 
level α test.  A two-sided (1-2α) x 100% Wald-type CI is calculated for the relative reduction in 
mean rate for, in this context, on treatment versus off. 
In the event that the data manifest excess zeros, zero-inflated (count) models provide a way of 
modeling the excess zeros by assuming there are two possible data generation processes 
(process 1 and process 2), and the result of a Bernoulli trial (eg, throwing a biased coin) 
determines which process is used for patient j: process 1 is chosen with probability φj and 
process 2 with probability 1- φj, and φj may depend on patient j’s baseline covariates (including 
study treatment), denoted as zj, typically via a logistic regression.  Process 1 generates only zero 
counts, whereas process 2 generates counts from either a Poisson or negative binomial 
distribution (which may depend on patient j’s baseline covariates (including study treatment), 
denoted as xj).  The set of baseline covariates z and x may be identical or may have some or no 
covariates in common. 
In a zero-inflated negative binomial model, the probability of {Yj = yj | xj} is: 
𝑃𝑃൫𝑌𝑌𝑗𝑗= 𝑦𝑦𝑗𝑗ห𝒙𝒙𝑗𝑗, 𝒛𝒛𝑗𝑗൯= ቐ
𝜑𝜑൫𝜸𝜸′𝒛𝒛𝑗𝑗൯+ ቀ1 −𝜑𝜑൫𝜸𝜸′𝒛𝒛𝑗𝑗൯ቁ𝑃𝑃𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁൫0ห𝒙𝒙𝑗𝑗൯   if 𝑦𝑦𝑗𝑗= 0
                    ቀ1 −𝜑𝜑൫𝜸𝜸′𝒛𝒛𝑗𝑗൯ቁ𝑃𝑃𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁൫𝑦𝑦𝑗𝑗ห𝒙𝒙𝑗𝑗൯   if 𝑦𝑦𝑗𝑗> 0
 
 
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10.2.8. 
Secondary Endpoint Analyses 
Secondary endpoints include change over time for eGFR.  Change over time will be summarized 
using repeated measures models starting from baseline.  Mean changes from baseline will be 
analyzed using a restricted maximum likelihood based repeated measure approach.  Summary 
statistics will be presented at baseline and follow-up time points and mean change from baseline 
will be estimated by eculizumab treatment status. 
The primary analyses will be repeated with a distinction for the time on eculizumab treatment as 
on-label or as on reduced/increased dosing regimen.  The focus will be on comparison of rates 
(ie, adjusted appropriately for exposure periods) of new TMA disease manifestations between:  
• time off eculizumab treatment and time on on-label eculizumab treatment, and  
• time on reduced/increased dosing of eculizumab treatment and time on on-label 
eculizumab treatment 
The number of occurrences of PE/PI per patient-years will be calculated and summarized by 
eculizumab treatment status. 
10.2.9. 
Safety Analyses 
Adverse events and general medical/surgical histories will be coded by primary system organ 
class (SOC) and preferred term using the Medical Dictionary for Regulatory Activities 
(MedDRA) (Version 13.0 or the most current).  All events from time of enrollment in the study 
will be included in the analyses. 
The number and percentage of patients with AEs will be summarized by preferred terms, SOC, 
severity (mild, moderate, severe), relationship to eculizumab treatment, and treatment status. If a 
patient has more than one occurrence of an AE, the most severe occurrence of the AE will be 
used in the severity summary table, and the strongest relationship to eculizumab treatment will 
be used in the relationship to eculizumab treatment table. 
Similarly, the number and percentage of patients with SAEs will be summarized by preferred 
terms, SOC, severity (mild, moderate, severe), relationship to eculizumab treatment, and 
treatment status. 
To account for differences in time spent on and off treatment, the number of AEs and SAEs per 
patient years will be calculated and summarized. 
The number and percentage of patients with AEs resulting in death, study withdrawal, and 
eculizumab treatment discontinuation will be summarized. 
10.2.10. 
Physical Examinations and Vital Signs 
Physical examinations will be collected at baseline for all patients and will be summarized.  Vital 
signs (systolic and diastolic BP, temperature, and sitting or lying HR), height (only for pediatric 
patients), and weight and changes from baseline in vital signs (including height and weight) will 
be summarized by visit.  Listings of physical examinations and vital signs will be produced. 
 
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10.2.11. 
Laboratory Assessments 
Changes from baseline in laboratory assessments (chemistry and hematology) will be 
summarized by visit. Likewise, shift tables (L [low], N [normal], H [high]) by visit and treatment 
status will be produced for clinical laboratory tests.  Listings of laboratory data will be produced.  
10.2.12. 
Exploratory Endpoint Analyses 
10.2.12.1. Pharmacokinetic/Pharmacodynamic/Biomarker Analyses 
Pharmacokinetic, PD (cRBC hemolytic assay), and biomarker analyses will be performed on all 
patients who have evaluable PK, PD, and biomarker data, respectively.   
Graphs of plasma eculizumab concentration time profiles for individual patients and for means 
will be provided.  Plasma eculizumab concentrations by collection day and time will be 
summarized by tabulations of mean, SD, median, minimum and maximum. Population PK 
analysis and PK-PD analyses will be conducted using eculizumab plasma concentrations, 
hemolytic activity and free C5 data, and selected biomarker data. PK and PK-PD model 
parameters and the variability will be estimated, and the potential covariates, such as 
demographics, disease severity, genetic markers, will be assessed.  Graphic exploration of 
exposure vs the selected efficacy or safety endpoints will be made, and subsequent exposure 
response analyses may be performed if graphic exploration suggests that a relationship exists.   
For PD and exploratory biomarker assessments, summary tabulations of mean, SD, median, 
minimum and maximum will be presented.  The relationship between changes in PD biomarkers, 
exploratory biomarkers, and the effects of eculizumab treatment, as well as the effects of 
treatment discontinuation, will be evaluated.   
For the exploratory biomarker analyses, the relationship between eculizumab concentration and 
the key and exploratory biomarkers or the correlation between clinical benefit and key 
exploratory biomarkers will be assessed by graphical display.  Potential relationships between 
clinical outcomes, PK/PD, genetic profile and biomarker levels will be explored.  Additional 
model-based exploratory analyses may be performed. 
Repeated measures model analyses similar to the ones performed for the change in eGFR will be 
conducted for biomarkers (Ba, TNFR1, sVCAM-1, TM, D-dimer, markers of renal injury (eg, 
Cystatin C)) to be measured in the study.  Summary statistics will be presented at baseline and 
follow-up time points and mean change from baseline will be estimated.  The number of 
occurrences per patient-years of (1) re-initiation of eculizumab treatment after discontinuation, 
(2) change from reduced/increased to labeled dosing, and (3) blood transfusion, will be 
calculated and summarized.  Summary statistics for proteinuria levels, FACIT-fatigue scores 
observed values and changes from baseline over time, and EORTC QLQ-C30 scale before and 
after discontinuation will be provided. Summary statistics (proportions) for patient reported 
aHUS symptoms, including severity, frequency, and impact will be reported before and after 
discontinuation. 
10.2.12.2. Genetic Analyses 
Genetic testing will include analysis of variants in genes known to be associated with aHUS.  
Additional exploratory genetic analyses may be performed to identify novel genetic variants 
 
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associated with aHUS or disease modifying genes.  Such variants may be validated by a second 
sequencing method and validated variants will be summarized across the study population. 
Potential relationships between clinical outcomes, treatment status, biomarkers, and genetic 
variants will be explored.   
10.2.13. 
Other Statistical Considerations 
10.2.13.1. Missing or Invalid Data 
Missing post-baseline data will not be imputed unless indicated in the described analysis in the 
SAP. 
10.2.13.2. Interim Analysis 
An interim analysis will be conducted dependent upon enrollment and data availability when 
approximately 1 year of follow-up data is available for analysis for 50% of the target sample. 
 
 
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11. 
DIRECT ACCESS TO SOURCE DATA/DOCUMENTS 
11.1. 
Study Monitoring 
Before a study site can enter a patient into this study, a representative of Alexion 
Pharmaceuticals, Inc. or its designee will communicate with the study site to: 
• Determine the adequacy of facilities and equipment 
• Discuss with the Investigator(s) and other personnel their responsibilities with regard 
to protocol adherence, and responsibilities of the Sponsor or its representatives. This 
will be documented in a Clinical Study Agreement between the Sponsor and the 
Investigator, as appropriate. 
During the study, a Sponsor’s representative or designee will have regular contact with the study 
site for the following: 
• Provide information and support to the Investigator(s) 
• Confirm that facilities and equipment remain acceptable 
• Confirm that all patients have been properly consented 
• Confirm that the study team is adhering to the protocol, that data are being accurately 
recorded in the CRFs/eCRFs 
• Perform source data verification. This includes a comparison of data in the 
CRFs/eCRFs with the patient’s medical records at the hospital or practice, and other 
records relevant to the study. This will require direct access to all original records for 
each patient (eg, clinic charts). 
• Record and report any protocol deviations not previously sent to the Sponsor. 
• Confirm that AEs and SAEs have been properly documented on CRFs/eCRFs, and 
confirm that any SAEs have been forwarded to the Sponsor.  Confirm that SAEs 
meeting criteria for reporting have been forwarded to the IRB. 
The monitor will be available between visits if the Investigator(s) or other staff needs 
information or advice. 
11.2. 
Data Capture System 
An electronic data capture (EDC) system will be used in this study.  The site maintains a separate 
source for the data entered by the site into the sponsor-provided EDC system.   
Data will be entered and stored in the EDC system, as applicable. Where possible, data from the 
M11-001 aHUS Registry may be used in combination with the data collected in this study in 
order to limit duplication of reporting or in program-level analysis of eculizumab patient data.  
Case report form data will be encoded and stored in a clinical trial database.  Data managed by a 
central vendor, such as laboratory test data, will be stored electronically in the central vendor’s 
database system.  Data will subsequently be transferred from the central vendor to the Sponsor.   
 
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11.3. 
Access to the Study Data  
All patients will be assigned a number upon enrollment in the study.  Patient details will be de-
identified as necessary.  Physicians will then enter data as periodic updates as required.  The 
Sponsor’s designee and automated email messages will remind the Investigator to update 
information in the study.  Investigators will have access to the secure database for entering 
patient data as well as accessing patient data already entered.  Paper copies of the CRF will also 
be available to the Investigator if required. 
11.4. 
Audits and Inspections 
Authorized representatives of the Sponsor, a regulatory authority, an EC, or an IRB may visit the 
site to perform audits or inspections, including source data verification. The purpose of an audit 
or inspection by the Sponsor is to examine systematically and independently, all study-related 
activities and documents, to determine whether study-related activities were conducted, and 
whether data were recorded, analyzed, and accurately reported, according to the protocol, Good 
Clinical Practice (GCP) guidelines of the International Council on Harmonisation (ICH), and any 
applicable regulatory requirements. The Investigator should contact the Sponsor immediately if 
contacted by a regulatory agency about an inspection. 
11.5. 
Institutional Review Board (IRB)/Independent Ethics Committee 
(IEC) 
The PI must obtain IRB /IEC approval for the investigation.  Initial IRB /IEC protocol approval, 
and all materials that have been submitted and approved by the IRB/EC for this study including 
the patient ICF and recruitment materials must be maintained by the Investigator and made 
available for inspection. 
11.6. 
Data Monitoring 
Due to the study’s observational nature with respect to eculizumab treatment, an independent 
data monitoring committee will not be implemented.  
12. 
QUALITY CONTROL AND QUALITY ASSURANCE 
To ensure compliance with GCP and all applicable regulatory requirements, the Sponsor or 
designee may conduct quality assurance audit(s) (Section 11.4). 
 
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13. 
ETHICS 
This study will be performed in accordance with ethical principles that have their origin in the 
Declaration of Helsinki and are consistent with ICH GCP guidelines. 
Investigators and other study personnel must comply with all instructions and regulations 
specified in this protocol, and applicable ICH GCP guidelines, and must conduct this study in 
accordance with all local, federal, and regulatory agency regulations. 
In accordance with ICH guidelines, pediatric participation in these studies should occur in 
qualified pediatric centers, with personnel who are properly trained and experienced in studying 
the pediatric population, and in evaluating and managing potential pediatric AEs. Site personnel 
should be knowledgeable and skilled in dealing with the pediatric population and its age 
appropriate needs, and be encouraged to use measures that minimize discomfort from procedures 
(eg, topical anesthesia to place IV catheters, use of indwelling catheters rather than repeated 
venipunctures for blood sampling, and collection of some protocol-specified blood samples when 
routine clinical samples are obtained). 
13.1. 
Ethics Review 
The final study protocol, including the final version of the ICF, must be approved or given a 
favorable opinion in writing by an IRB or EC, as appropriate.  The Investigator must submit 
written approval to the Sponsor before he/she can enroll any patient into the study. 
No modifications to the protocol should be made without the approval of both the Investigator 
and the Sponsor.  Changes that significantly affect patient safety, the scope of investigation, or 
scientific validity of the study will require IRB/EC notification prior to implementation, except 
where the modification is necessary to eliminate an apparent immediate hazard to patients.  Any 
deviations from protocol must be fully documented.  The Investigator is responsible for 
informing the IRB or EC of any amendment to the protocol, in accordance with local 
requirements.  In addition, the IRB or EC must approve all advertising used to recruit patients for 
the study.  The protocol must be reapproved by the IRB or EC upon receipt of amendments and 
annually, as local regulations require. 
The Investigator is also responsible for providing the IRB/IEC with any reportable serious 
adverse drug reactions from any other study conducted with the study drug.  The Sponsor will 
provide this information to the Principal Investigator. 
Progress reports and notifications of serious adverse drug reactions will be provided to the IRB 
or EC, according to local regulations and guidelines. 
13.2. 
Ethical Conduct of the Study 
The Investigator will conduct all aspects of this study in accordance with all national, provincial, 
and local laws of the pertinent regulatory authorities. 
 
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13.3. 
Written Informed Consent 
The Investigator at each center will ensure that the patient's parent or legal guardian is given full 
and adequate oral and written information about the nature, purpose, possible risk, and possible 
benefit of the study.  The patient's parent or legal guardian also must be notified that he/she is 
free to discontinue his/her child from the study at any time.  The parent or legal guardian should 
be given the opportunity to ask questions and time to consider the information provided. 
The signed and dated ICF must be obtained before conducting any study procedures. 
The Investigator(s) must maintain the original, signed and dated ICF.  A copy of the signed ICF 
must be given to the patient's parent or legal guardian. 
Should new information become available during the study that might affect the parent’s or legal 
guardian’s willingness to continue his/her child’s study participation, the parent or legal guardian 
will be notified in a timely manner about the new information and asked to sign a new ICF. 
 
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14. 
DATA HANDLING AND RECORDKEEPING 
14.1.1. 
Inspection of Records 
The Sponsor or designee will be allowed to conduct site visits for the purpose of monitoring any 
aspect of the study. The Investigator agrees to allow the monitor to inspect the patient charts, 
study source documents, and other records relative to study conduct. 
14.1.2. 
Retention of Records 
The Investigator must maintain all study-related documentation, in accordance with local 
retention requirements, for a period of 2 years after the last marketing application approval or, if 
not approved, 2 years following discontinuation of the test article for investigation. If it becomes 
necessary for the Sponsor or the regulatory authority to review any study-related documentation, 
the Investigator must permit access to such records. No records may be destroyed without 
Sponsor written approval. 
14.1.3. 
Retention of Biological Samples 
If a patient’s parent or legal guardian has provided consent for storage of biological samples, and 
if permitted by local regulatory authorities, any remaining sample will be stored at a central 
location for a maximum of 15 years after the last patient’s last study visit. These samples may be 
used for future exploratory biochemical or genetic tests to confirm aHUS diagnosis, to develop 
early diagnostic methods or to better understand the pathogenesis, course, and outcome of aHUS.  
If permitted according to local regulations and if patients or their guardian consent, blood 
samples may be used for additional exploratory aHUS-specific genetic analyses.   
Blood or DNA samples may be used for analysis of candidate genes believed to be responsible 
for aHUS in order to develop improved diagnostic methods. Blood or DNA samples may also be 
stored for future testing to discover novel variants in genes not previously known to be mutated 
in aHUS patients, to discover disease modifying genes, or to identify gene mutations which 
affect the PK or PD of eculizumab. The stored samples will not be used for any clinical study 
database with the exception of this study; however, the results obtained may be used to inform a 
future clinical study. All samples will be stored as de-identified under the patient ID number 
assigned at study enrollment. This will constitute a single code. Any results produced from 
genetic analysis will be double coded for de-identification by using a second code in place of the 
patient ID number to further protect patient privacy. The link between the patient ID number and 
the genetic results will be maintained and stored in a secure environment, with restricted access. 
The link will be used to facilitate correlation of genetic results with clinical data and allow for 
regulatory audit. Genetic samples can be traced for destruction via the patient ID number in the 
case of withdrawal of consent when the patient or consenting guardian has requested 
disposal/destruction of collected samples not yet analyzed. All other biochemical analyses not 
containing genetic data that are produced from stored samples, such as PK analyses or biomarker 
analyses, will be stored as de-identified under the patient ID number. 
 
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14.1.4. 
Data Privacy 
The Sponsor will make every effort to protect patient privacy.  For all study data collection, 
patients will be identified by a unique patient ID number and date of birth in regions where 
permitted.  All data will be securely stored with restricted access.  Genetic results will be further 
protected as described in Section 14.1.3.  Results from this study may be presented at meetings 
or in articles.  However, patient name or initials that could identify a patient will not be used in 
any such meetings or articles. 
 
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15. 
PUBLICATIONS 
The terms for publication are based on the permissions and responsibilities outlined in the study 
specific Clinical Trial Agreement. 
 
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16. 
REFERENCE LIST 
Ballermann BJ. Endothelial cell activation. Kidney Int. 1998 Jun;53(6):1810-26. 
Bu F, Maga T, Meyer NC, Wang K, Thomas CP, Nester CM, Smith RJ. Comprehensive genetic 
analysis of complement and coagulation genes in atypical hemolytic uremic syndrome. 
J.Am.Soc.Nephrol. 2014 Jan;25(1):55-64. 
Campistol JM, Arias M, Ariceta G, Blasco M, Espinosa M, Grinyo JM, Praga M, Torra R, 
Vilalta R, Rodriguez de CS. An update for atypical haemolytic uraemic syndrome: diagnosis and 
treatment. A consensus document. Nefrologia. 2013 Jan 18;33(1):27-45. 
Caprioli J, Noris M, Brioschi S, Pianetti G, Castelletti F, Bettinaglio P, Mele C, Bresin E, Cassis 
L, Gamba S, et al. Genetics of HUS: the impact of MCP, CFH, and IF mutations on clinical 
presentation, response to treatment, and outcome. Blood 2006 Aug 15;108(4):1267-79. 
Karpman D, Manea M, Vaziri-Sani F, Stahl AL, Kristoffersson AC. Platelet activation in 
hemolytic uremic syndrome. Semin Thromb.Hemost. 2006 Mar;32(2):128-45. 
Loirat C, Fakhouri F, Ariceta G, Besbas N, Bitzan M, Bjerre A, Coppo R, Emma F, Johnson S, 
Karpman D, et al. An international consensus approach to the management of atypical hemolytic 
uremic syndrome in children. Pediatr.Nephrol. 2016 Jan;31(1):15-39. 
Matis LA, Rollins SA. Complement-specific antibodies: designing novel anti-inflammatories. 
Nat.Med 1995 Aug;1(8):839-42. 
Nester CM, Barbour T, de Cordoba SR, Dragon-Durey MA, Fremeaux-Bacchi V, Goodship TH, 
Kavanagh D, Noris M, Pickering M, Sanchez-Corral P, et al. Atypical aHUS: State of the art. 
Mol.Immunol. 2015 Sep;67(1):31-42. 
Noris M, Caprioli J, Bresin E, Mossali C, Pianetti G, Gamba S, Daina E, Fenili C, Castelletti F, 
Sorosina A, et al. Relative role of genetic complement abnormalities in sporadic and familial 
aHUS and their impact on clinical phenotype. Clin.J.Am.Soc.Nephrol. 2010 Oct;5(10):1844-59. 
Zimmerhackl LB, Besbas N, Jungraithmayr T, Van de KN, Karch H, Karpman D, Landau D, 
Loirat C, Proesmans W, Prufer F, et al. Epidemiology, clinical presentation, and pathophysiology 
of atypical and recurrent hemolytic uremic syndrome. Semin Thromb.Hemost. 2006 
Mar;32(2):113-20. 
Zuber J, Fakhouri F, Roumenina LT, Loirat C, Fremeaux-Bacchi V. Use of eculizumab for 
atypical haemolytic uraemic syndrome and C3 glomerulopathies. Nat.Rev.Nephrol. 2012 
Nov;8(11):643-57. 
 
 
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APPENDIX 1. SUMMARY OF LABORATORY PANELS AND TESTS 
 
 
 
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APPENDIX 2. FACIT-FATIGUE ASSESSMENT FOR PEDIATRIC 
PATIENTS 
 
 
 
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APPENDIX 3.  FACIT-FATIGUE ASSESSMENT FOR ADULT 
PATIENTS 
 
 
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APPENDIX 4. EUROPEAN ORGANIZATION FOR RESEARCH AND 
TREATMENT OF CANCER QUALITY OF LIFE 
QUESTIONNAIRE (EORTC QLQ-C30) 
 
 
 
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APPENDIX 5. PATIENT-REPORTED aHUS SYMPTOMS 
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