Conditions: Hemophilia B
Allocation: NA | Intervention model: SINGLE_GROUP
Enrollment: 21
Healthy volunteers: no

Brief summary:
Phase 3/4, single arm, open-label study to evaluate PK, safety, and efficacy of APVO101 prophylaxis in severe or moderately severe hemophilia B subjects \< 12 years of age.

Detailed description:
Study APVO101-903 is a Phase 3/4, single arm, open-label clinical trial. The purpose of the study is to evaluate pharmacokinetics (PK), safety, and efficacy of APVO101 prophylaxis in severe or moderately severe hemophilia B subjects \< 12 years of age. The study is designed to gather information in two age groups of previously treated (with a minimum of 50 previous ED to factor IX replacement therapy) pediatric patients, specifically those \< 6 years of age and 6 to \<12 years of age.

Study APVO101-903 consists of three distinct phases:

* PK Phase - PK evaluation will consist of administration of a single 75 ± 5 IU/kg dose, followed by factor IX activity and safety assessments up to 50 hours post-infusion.
* Treatment Phase - subjects will receive APVO101 prophylaxis (starting prophylaxis dose to be determined based on APVO101 recovery; ideally within the recommended dose range: 35 - 75 IU/kg; twice weekly) for 50 ED (approximately 6 months).
* Continuation Phase - subjects may continue to receive APVO101 prophylaxis (recommended dose range: 35 - 75 IU/kg; twice weekly) for an additional ≥ 50 ED.

Arms:
arm 1: APVO101: 35 - 75 IU/kg; twice weekly

Interventions: intervention 1: APVO101
Intervention descriptions: intervention 1: Subjects will receive a single IV dose of APVO101 twice weekly or at a frequency of infusions as determined appropriate by the investigator for the particular study subject for a total of 50 ED. The starting prophylaxis dose will be based on APVO101 recovery from PK Phase assessments (only pre-infusion and 15-30 minute post-infusion samples).

Protocol document:
Prot_000.pdf: 
 
Confidential  
 
 
        1 
 
 
 
Protocol APVO101-903 
 
 
Evaluation of a Recombinant Factor IX Product, APVO101, in Previously-
Treated Pediatric Patients with Hemophilia B 
 
 
Version 3.0 
Amendment 2 Date: 29 July 2020 
 
 
Trial Sponsor: 
Medexus Pharma, Inc. 
 
d.b.a. Aptevo BioTherapeutics, LLC 
 
Medical Monitor: 
Maria Fico, M.D. 
 
+39 327 344 7053 (telephone) 
 
maria.fico@psi-cro.com 
 
Study Manager: 
Julissa Leon
 
+1 312.548.3125 (telephone)
 
+1 312.750.1082 (fax)
 
julissa.leon@medexus.com 
 
 
Confidentiality Statement 
This document contains confidential information of Medexus Pharma, Inc (Medexus) that must 
not be disclosed to anyone other than the recipient study staff and members of the Institutional 
Review Board/Ethics Committee. This information cannot be used for any purpose other than 
the evaluation or conduct of the clinical investigation without the prior written consent of 
Medexus. 
 


 
Confidential  
 
 
        2 
 
PROTOCOL SIGNATURE PAGE 
 
APVO101-903, Version 3.0, Amendment 2: 
Evaluation of a Recombinant Factor IX Product, APVO101, in Previously-Treated Pediatric 
Patients with Hemophilia B 
 
 
 
 
Clinical Site(s): 
 
 
 
My signature below verifies that I have read and agree to this protocol. I am aware of my 
responsibilities as an Investigator under the GCP guidelines of ICH, the Declaration of 
Helsinki, local regulations (as applicable) and the study protocol, and I agree to conduct 
the study according to these regulations. 
 
 
 
Site Principal Investigator: 
 
 
 
 
 
 
Principal Investigator Name (print) 
Title (print) 
 
 
 
 
 
 
Principal Investigator Signature 
Date (DD/MMM/YYYY) 
 
 


 
 
 
 
 
 
Protocol APVO101-903, Version 3.0, Amendment 2 
 
Confidential  
 
 
        3 
 
 
PROTOCOL SYNOPSIS 
Title 
Evaluation of a Recombinant Factor IX Product, APVO101, in 
Previously-Treated Pediatric Patients with Hemophilia B 
Sponsor 
Medexus Pharma, Inc. 
d.b.a Aptevo BioTherapeutics, LLC 
29 N Wacker Drive, Suite 704 
Chicago, IL 60606, USA 
Trial Start 
Anticipated enrollment of first subject: Q3 2019 
Objectives 
Primary Objectives 
• To evaluate safety of APVO101 in pediatric subjects with  
hemophilia B for at least 50 exposure days (ED) 
• To assess efficacy of APVO101 prophylaxis with respect to prevention 
of breakthrough bleeding and with respect to control of hemorrhaging 
in pediatric subjects with hemophilia B for at least 50 ED 
• To evaluate pharmacokinetics (PK) of APVO101 in pediatric subjects 
with hemophilia B 
• To evaluate APVO101 immunogenicity (development of inhibitory 
and non-inhibitory factor IX binding antibodies and antibodies to 
Chinese Hamster Ovary cell proteins [CHOP]) 
Exploratory Objectives 
• To evaluate markers of thrombogenicity [D-dimer, thrombin-
antithrombin III complex (TAT) and fragment 1+2 (F1+2)] during the 
first 24 hours post-infusion of APVO101 
• To evaluate efficacy of APVO101 for perioperative management in 
pediatric subjects with hemophilia B 
Subject 
Population 
Pediatric patients (< 11.5 years of age at first dose) with hemophilia B that 
have been previously treated with factor IX replacement therapy for ≥ 50 ED. 
Sample Size 
Up to 22 subjects will be enrolled in order to have 15 to 20 evaluable subjects 
(10 subjects < 6 years and 10 subjects 6 to < 12 years) complete the study (i.e., 
completion of PK assessments and a minimum of 50 ED). 
Number of Trial 
Sites 
Study APVO101-903 is a multi-center trial with international investigational 
sites; exact locations and number of the sites are to be determined. 
Test Product 
APVO101, a lyophilized coagulation factor IX (recombinant) for intravenous 
administration. 
Dosage 
PK Phase dose: a single infusion of 75 ± 5 IU/kg 
Treatment/Continuation Phase dose: a single infusion of APVO101 twice 
weekly or at a frequency determined appropriate by the investigator 


 
 
 
 
 
 
Protocol APVO101-903, Version 3.0, Amendment 2 
 
Confidential  
 
 
        4 
 
Title 
Evaluation of a Recombinant Factor IX Product, APVO101, in 
Previously-Treated Pediatric Patients with Hemophilia B 
(prophylaxis). The starting prophylaxis dose for but not limited to Treatment 
Phase will be based on APVO101 recovery; ideally within the recommended 
dose range of 35 – 75 IU/kg.  
Dose range for treatment of breakthrough, spontaneous or trauma-related 
bleeding episodes based on severity: 
• Minor or moderate bleeds: 40 – 60 IU/kg 
• Major or life-threatening bleeds: 60 – 100 IU/kg 
Dose for surgery: 
• Bolus infusion: up to 120 IU/kg within 1 hour prior to the start of the 
procedure, followed by an infusion of 60 IU/kg 12 hours after the first 
infusion and an infusion of up to 120 IU/kg 24 hours after the first 
infusion. Continue bolus infusions every 12 hours for a minimum of 
3 days post-procedure for major surgery or a minimum of 1 day 
post-procedure for minor surgery. The dosage and frequency of 
treatment may be adjusted at the discretion of the investigator. 
• Continuous infusion: target plasma level of factor IX between 70% and 
110% for a minimum of 3 days post- procedure for major surgery or a 
minimum of 1 day post-procedure for minor surgery. 
Protocol Design 
Phase 3/4, single arm, open-label study with three defined phases: 
PK Phase 
Initial PK evaluation – single dose of APVO101  
Treatment Phase 
APVO101 prophylaxis treatment for 50 ED 
Continuation Phase 
After completion of the Treatment Phase, subjects may continue APVO101 
prophylaxis treatment (for an additional ≥ 50 ED) 
Note: treatment with APVO101 to support a surgical procedure (if required) 
is permitted for subjects in Treatment Phase or Continuation Phase of the 
study. 
Inclusion Criteria 
1. Age: < 11.5 years of age at the time of the first dose and < 12 years 
throughout the Treatment Phase of the study (for at least 50 ED). 
2. Informed consent: subject’s parent or legal guardian written 
Institutional Review Board (IRB)/Ethics Committee (EC)-approved 
informed consent. An assent form (IRB/EC-approved) will be 
obtained, when required by local regulations/guidelines. 
3. Willingness and ability to make the required study visits and follow 
instructions while enrolled in the study (for at least 50 ED; 
approximately 6 months). 


 
 
 
 
 
 
Protocol APVO101-903, Version 3.0, Amendment 2 
 
Confidential  
 
 
        5 
 
Title 
Evaluation of a Recombinant Factor IX Product, APVO101, in 
Previously-Treated Pediatric Patients with Hemophilia B 
4. Documented severe or moderately severe hemophilia B diagnosis 
(factor IX activity ≤ 2 IU/dL); in addition, severity may be indicated 
by the occurrence of one or  more joint bleeding episode(s) at any point 
in the child’s medical history requiring infusion(s) to replace factor IX. 
5. Subjects must be on prophylaxis or switch to a prophylaxis regimen 
for the duration of the study. 
6. Previously treated patients with a minimum of 50 ED (as 
documented/determined by the investigator) to a preparation/blood 
components containing factor IX. 
7. Willingness to adhere to the 4-day washout period of any factor IX 
replacement therapy prior to PK evaluation. In case of previous 
exposure to a factor IX product with a prolonged half-life, a washout 
period of 3 half-lives is required in order to achieve steady state factor 
IX level prior to exposure to APVO101. 
8. Immunocompetent (CD4 count > 400/mm3) and not receiving immune 
modulating or chemotherapeutic agents. 
9. Platelet count at least 150,000/mm3. 
10. Liver 
function: 
alanine 
transaminase 
(ALT) 
and 
aspartate 
transaminase (AST) ≤ 2 times the upper limit of the normal range. 
11. Total bilirubin ≤ 1.5 times the upper limit of the normal range. 
12. Renal function: serum creatinine ≤ 1.25 times the upper limit of the 
normal range. 
13. Hemoglobin ≥ 7 g/dL. 
Exclusion 
Criteria 
1. History of factor IX inhibitor ≥ 0.6 Bethesda Units (BU); confirmed 
by the screening result.  
2. Existence of another coagulation disorder. 
3. Evidence of thrombotic disease, fibrinolysis, or disseminated 
intravascular coagulation (DIC). 
4. Use of an investigational drug within 30 days prior to study entry. 
5. Previous use of APVO101. 
6. Use of medications that could impact hemostasis, such as aspirin. 
7. Known hypersensitivity to the active substance or to any of the 
excipients in the investigational products. 
8. Known allergic reaction to hamster proteins. 
9. History of poor compliance, geographic isolation, unreliable 
transportation, a serious medical or social condition, or any other 
circumstance that, in the opinion of the investigator, would interfere 
with participation or compliance with the study protocol. 


 
 
 
 
 
 
Protocol APVO101-903, Version 3.0, Amendment 2 
 
Confidential  
 
 
        6 
 
Title 
Evaluation of a Recombinant Factor IX Product, APVO101, in 
Previously-Treated Pediatric Patients with Hemophilia B 
10. History of adverse reaction to either plasma-derived factor IX or 
recombinant factor IX that interfered with the subject’s ability to treat 
bleeding episodes with a factor IX product. 
11. History of any medical condition that would impact the efficacy 
evaluation and/or safety evaluation of the study product. 
Assessments 
Screening Assessments (21 to 5 days prior to PK Phase) 
Signed and dated Informed Consent Form (ICF) and/or assent form as 
applicable. 
Inclusion/exclusion criteria review. 
Medical and hemophilia-related history, including documentation of factor IX 
gene mutation, bleeding episode(s), documentation of PK data (e.g., recovery 
and half-life) utilizing prior non-study factor IX therapy, and documentation 
of at least 50 ED of factor IX replacement therapy 
Concomitant medications 
Demographics (age, sex), body weight, height, physical exam and vital signs 
Local laboratory assessments: 
• Serum chemistry [ALT, AST, alkaline phosphatase (ALP), blood urea 
nitrogen (BUN) or urea, uric acid, creatinine, total bilirubin, and 
glucose] 
• Complete blood count (CBC) with differential [hemoglobin, 
hematocrit, absolute counts and/or percent of: white blood cells, 
neutrophils, 
monocytes, 
lymphocytes, 
eosinophils, 
basophils, 
platelets, and red blood cells; mean platelet volume (MPV), mean 
corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), 
and mean corpuscular hemoglobin concentration (MCHC)] 
• CD4 count 
• Urinalysis [urine dipstick, followed by microscopy if abnormal] 
Central laboratory assessments: 
• Inhibitory factor IX antibodies (Nijmegen modified Bethesda assay) 
• Non-inhibitory factor IX binding antibodies 
• Anti-CHOP antibodies 
Review of subject diary of previous factor IX therapy (if available): infusions, 
bleeding summary, subject’s efficacy assessment, adverse events, and 
concomitant medications 
Investigator’s assessment of efficacy with previous factor IX therapy 
Assessment of major and target joint(s) 


 
 
 
 
 
 
Protocol APVO101-903, Version 3.0, Amendment 2 
 
Confidential  
 
 
        7 
 
Title 
Evaluation of a Recombinant Factor IX Product, APVO101, in 
Previously-Treated Pediatric Patients with Hemophilia B 
Assessment of adverse events  
Review of study requirements, subject diary instructions, and training on 
APVO101 reconstitution and administration 
PK Phase Assessments 
After a 4-day washout of factor IX replacement therapy or 3-half-lives 
washout of a factor IX product with a prolonged half-life, the following will 
be evaluated: 
Pre-infusion 
Physical exam, vital signs, body weight, height, and concomitant medications, 
updated medical history (if applicable) 
Central laboratory assessments: 
• Inhibitory factor IX antibodies (Nijmegen modified Bethesda assay: 
for subjects weighing > 28 kg) 
• Non-inhibitory factor IX binding antibodies (for subjects weighing > 
28 kg)  
• Anti-CHOP antibodies (for subjects weighing > 28 kg) 
• Factor IX activity 
• Thrombogenicity markers (see Table 2 for thrombogenicity 
assessments by subject weight) 
Post-infusion period 
Central laboratory assessments: 
• Factor IX activity at the following time points post-infusion: 
15-30 minutes, 4-6 hours, 24-26 hours and 46-50 hours 
• Thrombogenicity markers at 15-30 minutes, 4-6 hours and 
24-26 hours post-infusion (see Table 2 for thrombogenicity 
assessments by subject weight) 
Vital signs at each PK time-point post-infusion 
Assessment of adverse events 
Note: pre-infusion and 15-30 minute post-infusion samples will be tested for 
factor IX activity to determine starting prophylaxis dose. See section 5.7.1 for 
further details.  
Treatment Phase Assessments 
After the start of APVO101 prophylaxis treatment regimen the following 
assessments will be performed at: 
5 ED (± 1 ED) and 12 ED (± 2 ED) 
Central laboratory assessments: 
• Inhibitory factor IX antibodies (Nijmegen modified Bethesda assay) 


 
 
 
 
 
 
Protocol APVO101-903, Version 3.0, Amendment 2 
 
Confidential  
 
 
        8 
 
Title 
Evaluation of a Recombinant Factor IX Product, APVO101, in 
Previously-Treated Pediatric Patients with Hemophilia B 
• Non-inhibitory factor IX antibodies 
• Anti-CHOP antibodies 
• Mutation genotyping (12 ED visit only, if not documented); for 
patients below 10 kg this may be done at any time during the study 
when blood volumes allow 
Review of subject diary: infusions, bleeding summary, subject’s efficacy 
assessment, adverse events, concomitant medications and compliance 
Concomitant medications 
Assessment of adverse events 
Investigator’s assessment of efficacy 
25 ED (± 3 ED) and 50 ED (± 5 ED) 
Physical exam, vital signs, body weight, and height 
Concomitant medications 
Local laboratory assessments: 
• Serum chemistry (for patients below 17 kg, collect if blood volumes 
allow) 
• Complete blood count (CBC) with differential (for patients below 17 
kg, collect if blood volumes allow) 
• Urinalysis [urine dipstick, followed by microscopy if abnormal] 
Central laboratory assessments: 
• Inhibitory factor IX antibodies (Nijmegen modified Bethesda assay) 
• Non-inhibitory factor IX binding antibodies 
• Anti-CHOP antibodies 
Review of subject diary: infusions, bleeding summary, subject’s efficacy 
assessment, adverse events, concomitant medications, and compliance 
Assessment of adverse events 
Investigator’s assessment of efficacy 
Assessment of major and target joints (50 ED only) 
Continuation Phase Assessments: 
After completion of the Treatment Phase (i.e., 50 ED), subjects may continue 
with APVO101 treatment in a Continuation Phase (for an additional ≥ 50 ED). 
The following assessments in the Continuation Phase will be made at 75 ED 
(±5 ED), 100 ED (±5 ED) and every 3 months (~25 ED ± 5 ED) thereafter 
until end of study: 
Physical exam, vital signs, body weight, and height 
Concomitant medications 


 
 
 
 
 
 
Protocol APVO101-903, Version 3.0, Amendment 2 
 
Confidential  
 
 
        9 
 
Title 
Evaluation of a Recombinant Factor IX Product, APVO101, in 
Previously-Treated Pediatric Patients with Hemophilia B 
Local laboratory assessments: 
• Serum chemistry (for patients below 17 kg, collect if blood volumes 
allow) 
• Complete blood count (CBC) with differential (for patients below 17 
kg, collect if blood volumes allow) 
• Urinalysis [urine dipstick, followed by microscopy if abnormal] 
Central laboratory assessments: 
• Inhibitory factor IX antibodies (Nijmegen modified Bethesda assay) 
• Non-inhibitory factor IX binding antibodies 
• Anti-CHOP antibodies 
Review of subject diary: infusions, bleeding summary, subject’s efficacy 
assessment, adverse events, concomitant medications, and compliance 
Assessment of adverse events 
Investigator’s assessment of efficacy 
Assessment of major and target joints (100 ED visit only) 
Surgery Assessments (if applicable) 
Prior to surgery; pre-infusion 
Documentation of planned surgery including rationale 
Local laboratory assessment: 
Factor IX activity 
Central laboratory assessments: 
• Factor IX activity (if blood volumes allow) 
Vital signs 
Surgeon’s assessment of expected/estimated blood loss for the surgical 
procedure 
Prior to surgery; 5 – 30 minutes post-infusion (bolus) 
Local laboratory assessment: 
• Factor IX activity 
Central laboratory assessment: 
• Factor IX activity (if blood volumes allow) 
Assessment of adverse events 
During surgery 
Surgeon’s assessment of blood loss 
If study product is infused during surgery, local laboratory assessment: 
• Factor IX activity pre- and post-infusion (5-30 minutes) 


 
 
 
 
 
 
Protocol APVO101-903, Version 3.0, Amendment 2 
 
Confidential  
 
 
        10 
 
Title 
Evaluation of a Recombinant Factor IX Product, APVO101, in 
Previously-Treated Pediatric Patients with Hemophilia B 
Assessment of adverse events 
Use of blood products 
End of surgery 
Surgeon’s assessment of total blood loss for the surgical procedure 
Assessment of adverse events 
Use of blood products 
Post-surgery 
12 hours (±2 hours) post-initial infusion; pre-infusion 
Local laboratory assessment: 
• Factor IX activity 
Central laboratory assessment: 
• Factor IX activity (if blood volumes allow) 
Vital signs 
Surgeon’s assessment of blood loss 
Use of blood products 
12 hours post-initial infusion (±2 hours); 5 – 30 minutes post-infusion 
(bolus) 
Local laboratory assessment: 
• Factor IX activity 
Central laboratory assessment: 
• Factor IX activity (if blood volumes allow) 
Assessment of adverse events 
24 hours post-initial infusion (±3 hours); pre-infusion 
Local laboratory assessment: 
• Factor IX activity 
Central laboratory assessment: 
• Factor IX activity (if blood volumes allow) 
Vital signs 
Surgeon’s assessment of blood loss 
Use of blood products 
24 hours post-initial infusion (±3 hours); 5 – 30 minutes post- infusion 
(bolus) 
Local laboratory assessment: 
• Factor IX activity 
Central laboratory assessment: 


 
 
 
 
 
 
Protocol APVO101-903, Version 3.0, Amendment 2 
 
Confidential  
 
 
        11 
 
Title 
Evaluation of a Recombinant Factor IX Product, APVO101, in 
Previously-Treated Pediatric Patients with Hemophilia B 
• Factor IX activity (if blood volumes allow) 
Assessment of adverse events 
Factor IX activity (local laboratory assessment) should be monitored every 12 
hours (±2 hours) thereafter (for a minimum of 3 days post-surgery or until 
healing in case of a major surgery for major surgery or a minimum of 1 day 
post-procedure for minor surgery). Factor IX activity should be assessed 
before and within 30 minutes post-infusion of study product. If blood volumes 
allow, Factor IX activity should also be assessed by central laboratory at each 
timepoint. Adjustments in APVO101 dosing and timing post-surgery of each 
adjustment should be documented. Adverse events should be assessed for the 
duration of each continuous infusion period (±2 hours). 
In case of a major surgery (supported by bolus or continuous infusions), 
surgeon’s assessment of blood loss should be performed every 12 hours (±2 
hours) for at least 3 days post-surgery or until healing (if applicable). 
For continuous infusions, factor IX activity (local laboratory assessment), 
assessment of vital signs and use of blood products (pre-infusion) should be 
performed at 12-hour (±2 hours) and 24-hour (±3 hours) time points post-
surgery and subsequently on a daily basis or more frequently if needed until 
continuous infusion is discontinued. If blood volumes allow, Factor IX 
activity should also be assessed by central laboratory at each timepoint. 
Adjustments in APVO101 dosing and timing post-surgery of each adjustment 
should be documented. 
28 days (±7 days) post-factor IX replacement therapy for surgery 
Use of blood products 
End of Study or Early Withdrawal Assessments 
At the end of the study, or for subjects who prematurely terminate or who are 
withdrawn before the study is complete, the following will be evaluated: 
Physical exam, vital signs, body weight, height, and concomitant medications 
Assessment of adverse events 
Local laboratory assessments: 
• Serum chemistry (for patients below 17 kg, collect if blood volumes 
allow) 
• CBC with differential (for patients below 17 kg, collect if blood 
volumes allow) 
• Urinalysis [urine dipstick, followed by microscopy if abnormal] 
Central laboratory assessments: 
• Inhibitory factor IX antibodies (Nijmegen modified Bethesda assay) 
• Non-inhibitory factor IX binding antibodies 


 
 
 
 
 
 
Protocol APVO101-903, Version 3.0, Amendment 2 
 
Confidential  
 
 
        12 
 
Title 
Evaluation of a Recombinant Factor IX Product, APVO101, in 
Previously-Treated Pediatric Patients with Hemophilia B 
• Anti-CHOP antibodies 
Review of subject diary: infusions, bleeding summary, efficacy assessment, 
adverse events, concomitant medications and compliance 
Investigator’s assessment of efficacy 
Assessment of major and target joints 
Pharmacokinetic 
Endpoints 
The following PK endpoints will be calculated for subjects who complete the 
PK Phase: 
• Maximum post-infusion plasma concentration (Cmax) 
• Incremental recovery 
• In vivo recovery (IVR) 
• Area under the plasma concentration curve from time 0 to infinity  
(AUC0-∞) 
• Area under the plasma concentration curve from time 0 to t (AUC0-t) 
• Mean residence time (MRT) 
• Elimination rate constant (λZ) 
• Terminal half-life (t1/2) 
• Clearance (CL) 
• Volume of distribution at steady-state (Vdss) 
Efficacy 
Endpoints 
Primary Efficacy Endpoint: 
• Annualized bleeding rate (ABR) 
Secondary Efficacy Endpoints: 
The following secondary efficacy endpoints are evaluated at the bleeding 
episode level: 
• Subject rating of efficacy 
• Change in pain 
• Change in swelling 
• Time from onset of bleeding to the first infusion 
• Time from onset of treatment until resolution of the bleeding episode 
• Number of infusions required to treat the bleeding episode 
The following secondary efficacy endpoints are evaluated at the subject level: 
• Investigator rating of APVO101 prophylaxis efficacy 
• Investigator rating of APVO101 efficacy for control and management 
of bleeding episodes 
Exploratory Efficacy Endpoints: 


 
 
 
 
 
 
Protocol APVO101-903, Version 3.0, Amendment 2 
 
Confidential  
 
 
        13 
 
Title 
Evaluation of a Recombinant Factor IX Product, APVO101, in 
Previously-Treated Pediatric Patients with Hemophilia B 
The following endpoints will be calculated for surgical procedures (if 
applicable): 
• Surgeon assessment of estimated blood loss at time of surgery 
• Surgeon assessment of post-surgery blood loss (at 12-hour and 24-
hour post-surgery time points) 
Safety Endpoints 
The following assessments will be used to evaluate the safety: 
• Adverse events 
• Inhibitory factor IX antibodies 
• Non-inhibitory factor IX antibodies 
• Anti-CHOP antibodies 
• Thrombogenic markers 
Statistical 
Methods 
PK parameters will be listed and summarized. Descriptive statistics of PK 
parameters will be provided; no formal statistical test is planned. 
Descriptive summaries and listings will be provided for all efficacy endpoints. 
Summary statistics and listings will be provided for all safety endpoints. Also, 
incidence of non-inhibitory factor IX antibodies and incidence of anti-CHOP 
antibodies will be evaluated. 
Detailed description of the planned analyses will be provided in APVO101-
903 statistical analysis plan (SAP). 


 
Protocol APVO101-903, Version 3.0, Amendment 2 
 
Confidential  
 
              
 
 
 
 
 
 
 
 
14 
 
 
Schedule of Events 
Table 1: Schedule of Events for APVO101-903 
 
Screening12 
PK Phase 
Treatment Phase 
Continuation Phase 
End of Study or 
Early 
Termination 
5 
ED 
(±1 
ED) 
12 
ED 
(±2 
ED) 
25 
ED 
(±3 
ED) 
50 
ED 
(±5 
ED) 
75 
ED 
(±5 
ED) 
100 
ED 
(±5 
ED) 
Every 3 
months (~25 
ED ±5 ED) 
Evaluations 
 
Pre- 
infusion1 
Post- 
infusion2 
Informed consent and/or 
assent 
X 
 
 
 
 
 
 
 
 
 
 
Eligibility Criteria Review 
X 
 
 
 
 
 
 
 
 
 
 
Medical and hemophilia-
related history 
X 
X 
 
 
 
 
 
 
 
 
 
Demographics (age, sex) 
X 
 
 
 
 
 
 
 
 
 
 
Factor IX mutation 
assessment 
 
 
 
 
X10 
 
 
 
 
 
 
Concomitant medications 
X 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
Physical exam, body weight 
and height 
X 
X 
 
 
 
X 
X 
X 
X 
X 
X 
Vital signs 
X 
X 
X3 
 
 
X 
X 
X 
X 
X 
X 
Thrombogenic markers14 
 
X14 
X4,14 
 
 
 
 
 
 
 
 
CBC with differential 5 
X 
 
 
 
 
X15 
X15 
X15 
X15 
X15 
X15 
CD4 count13 
X 
 
 
 
 
 
 
 
 
 
 
Serum chemistry6 
X 
 
 
 
 
X15 
X15 
X15 
X15 
X15 
X15 
Inhibitor titer and non-
inhibitory factor IX binding 
antibodies9 
X 
X9 
 
X 
X 
X 
X 
X 
X 
X 
X 
Anti-CHOP antibodies 
X 
X16 
 
X 
X 
X 
X 
X 
X 
X 
X 
Assessment of major and/or 
target joints 
X 
 
 
 
 
 
X 
 
X 
 
X 


 
Protocol APVO101-903, Version 3.0, Amendment 2 
 
Confidential  
 
              
 
 
 
 
 
 
 
 
15 
 
 
Screening12 
PK Phase 
Treatment Phase 
Continuation Phase 
End of Study or 
Early 
Termination 
5 
ED 
(±1 
ED) 
12 
ED 
(±2 
ED) 
25 
ED 
(±3 
ED) 
50 
ED 
(±5 
ED) 
75 
ED 
(±5 
ED) 
100 
ED 
(±5 
ED) 
Every 3 
months (~25 
ED ±5 ED) 
Evaluations 
 
Pre- 
infusion1 
Post- 
infusion2 
Urinalysis7 
X 
 
 
 
 
X 
X 
X 
X 
X 
X 
Factor IX activity11 
 
X 
X 
 
 
 
 
 
 
 
 
Adverse events 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Efficacy/subject diary8 
X 
 
 
X 
X 
X 
X 
X 
X 
X 
X 
Training on subject diary and 
APVO101 reconstitution and 
administration 
X 
 
 
 
 
 
 
 
 
 
 
1 From 2 hours to 15 minutes pre-infusion. 
2 At 15-30 minutes, 4-6 hours, 24-26 hours and 46-50 hours post-infusion of 75 ± 5 IU/kg (PK dose). 
3 Vital signs (pulse rate, blood pressure, respiratory rate and temperature) at 15-30 minutes, 4-6 hours, 24-26 hours and 46-50 hours post-infusion of PK dose. 
4 Thrombogenicity marker assessments at 15-30 minutes, 4-6 hours and 24-26 hours post-infusion of PK dose.  
5 Includes hemoglobin, hematocrit, absolute counts of: white blood cells, neutrophils, monocytes, lymphocytes, eosinophils, basophils, platelets and red blood 
cells; mean platelet volume (MPV), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration 
(MCHC) to be assessed at a local laboratory. 
6 Includes ALT, AST, ALP, BUN or urea, uric acid, creatinine, total bilirubin and glucose to be assessed at a local laboratory. 
7 Urine dipstick, followed by microscopy if abnormal to be assessed at a local laboratory. 
8 Investigator’s efficacy assessment and review of subject’s diary including infusions, bleeding summary, subject’s efficacy assessment, adverse events and 
concomitant medications. At Screening, review of subject diary to include review of previous factor IX therapy (if available). 
9 Inhibitory and non-inhibitory factor IX antibodies to be assessed by central lab at PK Phase Pre-infusion for subjects weighing ≥ 28 kg, and all subjects at all 
other time points. 
10 Factor IX mutation assessment to include mutation genotyping by central laboratory if not previously documented. For patients below 10 kg this may be done  
at any time during the study when blood volumes allow 
11 Factor IX activity to be assessed by central lab pre-infusion and post-infusion at 15-30 minutes, 4-6 hours, 24-26 hours, and 46-50 hours. Pre-infusion and 
15 to 30 minutes post-infusion samples will be tested for factor IX activity to determine the starting prophylaxis dose. See section 5.7.1 for further details. 
12 Screening to occur 21 to 5 days prior to PK phase. 
13  CD4 count to be assessed by local laboratory. 
14 See Table 2 for thrombogenicity assessments by subject weight; thrombogenicity markers include D-dimer, TAT complex, fragment 1+2. 
15 For patients below 17 kg, CBC with differential and serum chemistry should be collected if blood volumes allow. 
16 Anti-CHOP antibodies to be assessed by central laboratory at PK phase pre-infusion for subjects weighing ≥ 28 kg 
 


 
Protocol APVO101-903, Version 3.0, Amendment 2 
 
Confidential  
 
              
 
 
 
 
 
 
 
 
16 
 
Table 2: Thrombogenicity Assessments During PK Phase by Subject Weight  
Subject weight 
Pre-infusion 
15-30 min post-infusion 
4-6 hours post-infusion 
24-26 hours post-infusion 
≥ 20 kg 
X 
X 
X 
X 
≥ 17 kg to <20kg 
X 
X 
 
X 
< 17 kg1 
 
 
 
 
1 To accommodate blood volume limitations for subjects < 17 kg, no thrombogenicity assessments will be performed during the PK Phase. Thrombogenicity 
assessments may be drawn at these timepoints during the Treatment Phase when blood volume limitations allow. 
 
Table 3: Schedule of Events for a Surgical Procedure (if required during Treatment Phase and/or Continuation Phase)  
 
Prior to surgery1 
During 
surgery 
End of 
surgery 
12 hours post-
surgery 
24 hours post-
surgery2 
28 days (±7 days) post-
factor IX replacement 
therapy for surgery 
Evaluations 
Pre-
infusion 
Post-
infusion (5-
30 min) 
 
 
Pre-
infusion 
Post-
infusion 
(5-30 
min) 
Pre-
infusion 
Post-
infusion 
(5-30 
min) 
Factor IX activity3 
X 
X 
X4 
 
X 
X 
X 
X 
 
Vital signs 
X 
 
 
 
X 
 
X 
 
 
Adverse events 
 
X 
X 
X 
 
X 
 
X 
 
Use of blood products 
 
 
X 
X 
X 
 
X 
 
X 
Surgeon’s assessment of 
expected/estimated blood 
loss 
X 
 
 
X 
X 
 
X 
 
 
1  If using bolus infusions, an infusion of up to 120 IU/kg will be given within 1 hour prior to the start of the procedure, followed by an infusion of 
approximately 60 IU/kg 12 hours after the first infusion and an infusion of up to 120 IU/kg 24 hours after the first infusion. If administering a continuous 
infusion, the plasma factor IX activity should range between 70% and 110%, and the dose and timing of subsequent infusions and adjustments should be 
recorded and guided by factor IX activity results.  
2  Continue with bolus or continuous infusion treatment for as long as the surgeon deems necessary, but for a minimum of 3 days post-surgery for major surgery or a 
minimum of 1 day post-procedure for minor surgery. Assess pre- and post-infusion factor IX activity every 12 hours. 
3  Factor IX activity is to be assessed by the local laboratory at all time points. If blood volumes allow, factor IX samples should also be assessed by the central 
laboratory. 
4  If study product is infused during surgery, measure factor IX activity pre- and post-infusion (5-30 minutes). 
 
 
 


 
   
 
   Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        17 
 
TABLE OF CONTENTS 
PROTOCOL SYNOPSIS ................................................................................................................ 3 
Schedule of Events ................................................................................................................. 14 
1. 
BACKGROUND INFORMATION ........................................................................... 23 
1.1. 
Introduction ................................................................................................................ 23 
1.2. 
Trial Drug ................................................................................................................... 24 
1.2.1. Description of Trial Drug ........................................................................................... 24 
1.2.2. Summary of Findings from Clinical Trials with APVO101 ...................................... 24 
1.2.3. Benefit:Risk Ratio of APVO101 ................................................................................ 26 
1.3. 
Clinical Trial Rationale .............................................................................................. 27 
2. 
TRIAL OBJECTIVES AND PURPOSE ................................................................... 28 
2.1. 
Primary Objectives ..................................................................................................... 28 
2.2. 
Exploratory Objectives ............................................................................................... 28 
3. 
TRIAL DESIGN ........................................................................................................ 29 
3.1. 
Trial Design ................................................................................................................ 29 
3.2. 
Anticipated Centers .................................................................................................... 30 
3.3. 
Sample Size ................................................................................................................ 30 
3.4. 
Criteria for Stopping or Terminating the Trial ........................................................... 30 
4. 
SELECTION AND WITHDRAWAL OF SUBJECTS ............................................. 32 
4.1. 
Subject Inclusion Criteria ........................................................................................... 32 
4.2. 
Subject Exclusion Criteria .......................................................................................... 33 
4.2.1. Subject Withdrawal .................................................................................................... 33 
4.2.2. Subject Withdrawal Criteria ....................................................................................... 33 
4.2.3. Subject Replacement .................................................................................................. 34 
4.2.4. Follow-up for Withdrawn Subjects ............................................................................ 34 
5. 
TRIAL MEDICATION .............................................................................................. 35 
5.1. 
Packaging and Formulation ........................................................................................ 35 
5.2. 
Labeling ...................................................................................................................... 35 
5.3. 
Storage Conditions ..................................................................................................... 35 
5.4. 
Preparation and Administration.................................................................................. 36 


 
   
 
   Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        18 
 
5.5. 
Medication Shipment ................................................................................................. 36 
5.6. 
Drug Accountability ................................................................................................... 36 
5.7. 
APVO101 Dosing ...................................................................................................... 37 
5.7.1. Dose and Schedule ..................................................................................................... 37 
5.7.2. Dose Modifications .................................................................................................... 38 
5.7.3. Treatment Compliance ............................................................................................... 39 
6. 
TRIAL PROCEDURES ............................................................................................. 40 
6.1. 
Screening (21 to 5 days prior to PK Phase) ............................................................... 40 
6.2. 
Pharmacokinetic (PK) Phase Assessments................................................................. 41 
6.3. 
Treatment Phase Assessments .................................................................................... 41 
6.3.1. Surgery Assessments .................................................................................................. 42 
6.4. 
Continuation Phase Assessments ............................................................................... 45 
6.4.1. Surgery Assessments .................................................................................................. 46 
6.5. 
End of Study or Early Withdrawal Assessments........................................................ 46 
6.6. 
Handling of Samples .................................................................................................. 46 
6.7. 
Shipment of Samples .................................................................................................. 46 
6.8. 
Concomitant Medications........................................................................................... 47 
6.9. 
Excluded Concomitant Medications .......................................................................... 47 
7. 
ASSESSMENT OF APVO101 PHARMACOKINETICS ........................................ 48 
8. 
ASSESSMENT OF APVO101 EFFICACY .............................................................. 49 
8.1. 
Subject’s Assessment of Efficacy .............................................................................. 49 
8.2. 
Investigator’s Assessment of Efficacy ....................................................................... 49 
8.3. 
Surgeon’s Assessment of Efficacy ............................................................................. 51 
9. 
ASSESSMENT OF SAFETY .................................................................................... 52 
9.1. 
Definitions of Adverse Event, Serious Adverse Event and Adverse Drug 
Reaction............................................................................................................... 52 
9.1.1. Definition of an Adverse Event .................................................................................. 53 
9.1.2. Definition of a Serious Adverse Event ....................................................................... 54 
9.1.3. Definition of an Adverse Drug Reaction .................................................................... 55 
9.2. 
Assessment of Severity (Intensity) and Causality ...................................................... 55 
9.2.1. Assessment of Severity (Intensity) ............................................................................. 55 


 
   
 
   Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        19 
 
9.2.2. Assessment of Causality (ICH Classification) ........................................................... 55 
9.3. 
Description of Current Safety Profile for APVO101 ................................................. 56 
9.4. 
Adverse Event Reporting ........................................................................................... 57 
9.5. 
Reporting of SAEs ..................................................................................................... 57 
9.6. 
Safety Data Monitoring .............................................................................................. 58 
10. 
OTHER ASSESSMENTS .......................................................................................... 59 
10.1. Assessment of Major and Target Joint(s) ................................................................... 59 
10.2. Subject-reported Assessments .................................................................................... 59 
10.3. Mutation Genotyping ................................................................................................. 59 
11. 
STATISTICAL ISSUES IN TRIAL DESIGN ........................................................... 60 
11.1. Sample Size Calculation ............................................................................................. 60 
11.2. Clinical Trial Endpoints ............................................................................................. 60 
11.2.1. PK Endpoints .............................................................................................................. 60 
11.2.2. Efficacy Endpoints ..................................................................................................... 61 
11.2.3. Safety Endpoints ........................................................................................................ 61 
11.3. Interim Analyses ......................................................................................................... 62 
11.4. Planned Method of Analyses ...................................................................................... 62 
11.4.1. PK Analysis ................................................................................................................ 62 
11.4.2. Efficacy Analysis ....................................................................................................... 62 
11.4.3. Safety Analysis ........................................................................................................... 62 
12. 
REGULATORY AND ETHICAL ISSUES ............................................................... 63 
12.1. Declaration of Helsinki .............................................................................................. 63 
12.2. Informed Consent / Assent ......................................................................................... 63 
12.3. Institutional Review Board (IRB) / Ethics Committee (EC) ...................................... 63 
12.4. Documentation Required Prior to Trial Initiation ...................................................... 63 
12.5. Subject Confidentiality ............................................................................................... 64 
13. 
ADMINISTRATIVE AND LEGAL REQUIREMENTS .......................................... 65 
13.1. Sponsorship ................................................................................................................ 65 
13.2. Protocol Amendments ................................................................................................ 65 
13.3. Deviations from the Protocol ..................................................................................... 65 
13.4. Source Documentation and Storage ........................................................................... 65 


 
   
 
   Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        20 
 
13.5. Data Forms ................................................................................................................. 66 
13.6. Monitoring .................................................................................................................. 67 
13.7. Quality Control and Quality Assurance ..................................................................... 67 
13.8. Publication Policy ...................................................................................................... 67 
14. 
REFERENCES ........................................................................................................... 68 
 
LIST OF TABLES 
Table 1: Schedule of Events for APVO101-903 ........................................................................... 14 
Table 2: Thrombogenicity assessments during PK Phase by subject weight ................................ 16 
Table 3: Schedule of Events for a Surgical Procedure (if required during Treatment Phase 
and/or Continuation Phase) in APVO101-903 ........................................................... 16 
Table 4: Causality Assessments of Reported Adverse Events ...................................................... 56 
 
LIST OF FIGURES 
Figure 1: 
Overview of APVO101-903 Design .......................................................................... 29 
 
 
 


 
   
 
   Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        21 
 
List of Abbreviations 
ABR 
 
Annualized bleed rate 
ADR 
 
Adverse drug reaction 
AE 
 
Adverse event  
 
ALP 
 
Alkaline phosphatase 
ALT 
 
Alanine transaminase 
AST 
 
Aspartate aminotransferase 
AUC0-day 7 
 
Area under the plasma concentration curve from time 0 to day 7 
AUC0-∞ 
 
Area under the plasma concentration curve from time 0 to infinity 
AUC0-t  
Area under the plasma concentration curve from time 0 to the last measurable 
concentration 
BUN 
 
Blood urea nitrogen 
CBC 
 
Complete blood count 
CFR 
 
Code of federal regulations title 21 
Cl 
 
Drug clearance rate 
Cmax 
 
Maximum serum concentration 
CHO 
 
Chinese hamster ovary cells 
CHOP 
 
Chinese hamster ovary cell proteins 
CRO 
 
Contract research organization 
CRF 
 
Case report form 
DIC 
 
Disseminated intravascular coagulation 
EC 
 
Ethics committee 
ED 
 
Exposure day 
EDC 
 
Electronic data capture 
EU 
 
European Union 
FIX 
Factor IX 
GCP 
 
Good clinical practices 
HIC 
 
 
 
 
Hydrophobic interaction chromatography 
EC 
Ethics committee 
ICF 
 
 
 
 
Informed consent form 
ICH 
 
 
 
 
International conference on harmonization 


 
   
 
   Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        22 
 
IgG 
 
 
 
 
Immunoglobulin G 
IRB 
 
 
 
 
Institutional review board 
IV 
Intravenous 
PK  
 
 
 
 
Pharmacokinetics 
PIP 
 
 
 
 
Pediatric Investigation Plan 
PTP 
 
 
 
 
Previously-treated patient 
PTT 
 
 
 
 
Partial thromboplastin time 
SAE 
 
 
 
 
Serious adverse event 
SAP 
 
 
 
 
Statistical analysis plan 
TAT 
 
 
 
 
Thrombin-antithrombin complex 
Vss  
 
 
 
 
Volume of distribution at steady state 
WHO  
 
 
 
World Health Organization 
WFH  
 
 
 
World Federation of Hemophilia 
WFI 
 
 
 
 
Water for injection 
 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        23 
 
1. 
BACKGROUND INFORMATION 
1.1. 
Introduction 
Hemophilia is an inherited clotting factor disorder; the two most prevalent types of hemophilia are 
types A and B (1). Hemophilia B (congenital factor IX deficiency) is usually caused by an X-linked 
recessive trait carried by females with one defective factor IX gene. Fifty percent of their male 
offspring will have the disease and 50% of their female offspring will be carriers. In about 30% of 
cases, there is no family history of the disorder and the condition results from spontaneous factor IX 
gene mutation. Hemophilia disorder occurs in about 1 out of 10,000 births; with hemophilia B being 
considered a rare disorder, representing 15–20% of hemophilia patients (2). 
Severity of hemophilia B can be defined based on the level of factor IX (% of normal factor IX 
activity) as severe (< 1% factor IX activity), moderate (1–5% factor IX activity) or mild (5–40% factor 
IX activity) (3). Patients with < 2% but > 1% factor IX activity are sometimes referred to as moderately 
severe hemophilia B patients. Severe forms of hemophilia become apparent early in life, at 
circumcision, or when the infant becomes mobile, whereas mild cases may go unnoticed until they 
occur in response to surgery or trauma. In severe cases, internal bleeding may occur anywhere and 
bleeding into joints is common (3). Due to joint bleeding, problems associated with hemophilia 
include possible joint deformity, reductions in mobility and arthritis (4). 
The primary aim of care for hemophilia patients is to prevent and treat bleeding with the deficient 
clotting factor, in case of hemophilia B, factor IX. People with hemophilia are best managed in a 
comprehensive care setting, however, whenever appropriate and possible, persons with hemophilia 
should be managed in a home therapy setting. Clinical study outcomes have demonstrated 
conclusively that immediate dosing of replacement factor concentrate at the initiation of a bleeding 
episode significantly minimizes the most significant morbidities associated with the condition (3). 
The World Federation of Hemophilia (WFH) strongly recommends the use of viral-inactivated 
plasma-derived or recombinant concentrates for the treatment of hemophilia (3). The mainstay, with 
respect to treatment regimens, is prophylactic factor replacement to prevent anticipated bleeding. This 
prevents bleeding and joint destruction and should be the goal of therapy to preserve normal 
musculoskeletal function. The WFH recommends primary prophylaxis (start of prophylactic treatment 
after first joint bleed) or secondary prophylaxis (prophylactic regimen after second joint bleed) in 
pediatric patients < 12 years of age (3). 
Prophylaxis is also recommended after the onset of joint disease (tertiary prophylaxis). 
Ultimately, the dosing protocol for any patient should be individualized as much as possible based on 
age, weight, venous access, bleeding phenotype, activity, and availability of clotting factor 
concentrates (3). 
Currently, there are five marketed recombinant factor IX products for use in children < 12 years of 
age with hemophilia B; two factor IX products produced in Chinese Hamster Ovary (CHO) cell lines 
with conventional half-life: BeneFIX® (nonacog alfa); marketed since 1997 in the United States (US) 
and European Union (EU), and RIXUBIS® (nonacog gamma); marketed since 2014 in the US and EU 
(5, 6) and three prolonged half-life factor IX products: ALPROLIX® (eftrenonacog alfa) a factor IX 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        24 
 
molecule covalently linked to the Fc-domain of human IgG1 and produced in a human embryonic 
kidney (HEK) cell line; and marketed since 2014 in the US, Canada, Japan and Australia, 
IDELVION® (albutrepenonacog alfa), generated by the genetic fusion of recombinant albumin to 
recombinant factor IX, produced in CHO cells, and marketed since 2016 in the US, EU, and Canada, 
and REBINYN® (nonacog beta pegol), a glycoPEGylated recombinant DNA-derived factor IX; 
marketed since 2018 in the US (7, 8, 9).  
APVO101 (conventional half-life recombinant factor IX) is licensed in the US (as IXINITY®) for 
control and prevention of bleeding episodes, and for perioperative management in hemophilia B 
patients ≥ 12 years of age. Although APVO101 has been administered to pediatric previously-treated 
patients (PTPs) < 12 years of age during the clinical development (see Section 1.2.2), additional data 
in PTPs < 12 years of age are required to satisfy regulatory a post-marketing requirement (i.e., 
20 pediatric [< 12 years of age] PTPs with 50 exposure days [ED]) (see Section 1.3). 
1.2. 
Trial Drug 
1.2.1. 
Description of Trial Drug 
APVO101 is a 415 amino acid, single chain glycoprotein with a molecular weight of approximately 
55,000 daltons. The primary amino acid sequence of APVO101 is comparable to the Thr148 allelic 
form of plasma-derived factor IX. The recombinant glycoprotein contains 8 glycosylated residues 
(2 N-linked, and 6 O-linked), with carbohydrate representing approximately 13% of the total 
glycoprotein weight and has 11 intrachain disulfide bonds (10). 
APVO101 (recombinant coagulation factor IX) is produced in a CHO cell line and the manufacture 
of APVO101 is accomplished using typical fermentation, harvest, and purification unit operations 
used in the biotechnology industry, and it is fully compliant with the relevant guidance (ICH Q5A). 
In addition, the manufacturing process for APVO101 contains a step to reduce CHO protein (CHOP) 
content.  
APVO101 has been developed as a lyophilized product, which, after reconstitution with sterile water-
for-injection (WFI), is intended for intravenous (IV) administration. There are no novel excipients in 
the product formulation, and all excipients are generally regarded as safe (as per 21 CFR 330.1). 
For more information, refer to Section 5. 
1.2.2. 
Summary of Findings from Clinical Trials with APVO101 
Pharmacokinetics (PK), safety and efficacy of APVO101 have been evaluated in study IB1001-01 
with predominantly adolescent/adult (≥ 12 years of age) PTPs with severe or moderately severe (factor 
IX activity ≤ 2%) hemophilia B. A total of 77 subjects (in the US, Europe, Israel and India) were 
screened and enrolled in the study; there were three US subjects < 12 years of age who were enrolled 
into the study (exclusive of PK assessments). There were 32 subjects enrolled in a randomized PK 
Phase to evaluate non-inferiority of APVO101 to commercially available recombinant factor IX 
product (BeneFIX). The results of the PK Phase demonstrated that APVO101 is non-inferior to 
BeneFIX with respect to its pharmacokinetic profile, in particular AUC0-∞, AUC0-72 hours, and Cmax. 
The incremental recovery (IU/dL per IU/kg) in adolescent and adult PTPs was 0.98. The initial PK 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        25 
 
profile of APVO101 was comparable when repeated (n=14) 5.8 months (median) after its initial 
evaluation suggesting a stable profile over time and across product lots. 
The majority of the PK subjects (n = 29) continued into the Treatment and Continuation phases of the 
study where long-term clinical efficacy and safety of APVO101 were evaluated; a total of 61 subjects 
received prophylaxis treatment (median dose: 53 IU/kg), while 12 subjects received on-demand 
(median dose: 57 IU/kg). There were 55 subjects with 50 ED to APVO101 and 45 subjects with 100 
ED. The median annualized bleeding rate (ABR) for subjects on prophylaxis was 1.52, while for on-
demand subjects it was 16.4. Overall, efficacy of APVO101 in the prevention and treatment of 
bleeding episodes has been shown to be satisfactory. This is supported by the investigator and subject 
assessments of APVO101 efficacy, by the demonstrated prevention of bleeding episodes in subjects 
on adequate and compliant prophylaxis regimens, and by control of hemorrhages. 
In addition, APVO101 was well tolerated with no evidence of inhibitor development in any subject. 
Adverse drug reactions (i.e., adverse events related to APVO101) were reported in 3.3% of subjects, 
with headache being the most frequent adverse reaction (2.6% of subjects); all adverse drug reactions 
were mild or moderate. 
As part of study IB1001-01, a surgery sub-study was conducted to evaluate APVO101 for 
perioperative management of major surgical procedures. APVO101 was administered during major 
surgical procedures as bolus (n = 13) or continuous infusion (n = 6). APVO101 was rated as adequate 
or better in controlling hemostasis post-surgery as assessed by the surgeon when used in various 
procedures, including, knee arthroplasty (n = 8), elbow arthroplasty (n = 2), knee amputation (n = 1), 
percutaneous Achilles tendon lengthening (n = 1), open inguinal hernia repair (n = 1), tibiotalar fusion 
(n = 1), arthroscopic synovectomy (n = 2), and debridement (ankle, knee) (n = 3). In all instances, 
blood loss at surgery was ‘expected’ or ‘less than expected’ as assessed by the surgeon. These data 
indicate that APVO101 can be effectively and safely used for perioperative management. 
Subjects in IB1001-01 were routinely monitored for development of antibodies to CHOP; 20 out of 
68 subjects (29%) developed antibodies to CHOP (anti-CHOP). These antibodies had no effect on the 
safety or efficacy profile of APVO101. However, the clinical trials in the US were put on clinical hold 
by the FDA. To address the issue of CHOP, the APVO101 manufacturing process was minimally 
modified in order to decrease the amount of host cell (CHOP) in APVO101 drug substance and drug 
product. To reduce CHOP, a hydrophobic interaction chromatography (HIC) column (phenyl 
sepharose resin) was implemented after the final chromatography step and prior to viral inactivation. 
The newly added chromatography step was optimized to provide maximum reduction of CHOP from 
APVO101 (“polished” APVO101 drug product). Extensive biochemical and molecular 
characterization comparability studies have demonstrated that former APVO101 (pre-HIC process) 
and polished APVO101 are comparable. Based on these comparability results, the FDA lifted the 
clinical hold on APVO101 clinical trials and allowed introduction of polished APVO101 into ongoing 
subjects. 
Following transition to polished APVO101 treatment, anti-CHOP positive subjects (n=4) exhibited 
decline in anti-CHOP titers; also, no new anti-CHOP positive test results were observed in previously 
anti-CHOP negative subjects (n=10), further demonstrating the effectiveness of the manufacturing 
process change. 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        26 
 
Furthermore, APVO101 has been evaluated for PK, safety and efficacy in study IB1001-02 with 
severe or moderately severe (factor IX activity ≤ 2%) hemophilia B PTPs < 12 years of age. Nine 
pediatric subjects (3 subjects < 6 years and 6 subjects 6-12 years) were enrolled in the study (all were 
prescribed a prophylaxis regimen following PK assessment; one subject erroneously received on-
demand treatment). 
The median ED for patients on prophylactic treatment was 221 (range 111-404) and the median time 
between first and last treatment was 46 months. The median total number of bleeds per patient 
was 1 (range 0-6); two patients experienced no bleeds. The median annualized bleed rate 
was 0.3 (range 0-1.6). The patient who received treatment on demand experienced 23 bleeds with an 
annualized bleed rate of 11. No adverse events related to APVO101 were reported. None of the 
patients developed factor IX inhibitors during the study. 
During the course of the study, three subjects developed anti-CHOP antibodies (with no apparent 
effect on safety or efficacy of APVO101), while six subjects were negative. Following transition to 
polished APVO101 treatment, the three anti-CHOP positive subjects displayed declining anti-CHOP 
titers, while the remaining 4 subjects displayed anti-CHOP negative results. 
For further summary of clinical trial data on APVO101, refer to the most current APVO101 
Investigator’s Brochure. 
1.2.3. 
Benefit:Risk Ratio of APVO101 
In its pivotal clinical trial (IB1001-01) in patients with hemophilia B aged ≥ 12-years-old, APVO101 
was shown to have a non-inferior PK profile when compared to BeneFIX. In addition, APVO210 
was demonstrated to control and manage breakthrough and other bleeding episodes during the 
treatment phase (which included 3 patients < 12-years-old on an exception basis) and was assessed by 
surgeons to provide expected or better than expected hemostatic control during major surgical 
procedures. The most common adverse event related to APVO101 according to the investigator was 
headache which was reported by 2.6% of patients. Based on these data, APVO101 was FDA approved 
for marketing in the United States.  
APVO101 has also been studied in 9 patients with hemophilia B < 12-years-old when used as 
prophylaxis (IB1001-02). In this preliminary study, APVO101 provided effective bleed prevention 
and management with a median number of ED of 221. There were no subjects who had drug-related 
adverse events. 
There are potential risks with APVO101, as with any recombinant factor IX therapy. One potential 
risk is the development of factor IX inhibitory antibodies (inhibitors). To date, there have been no 
inhibitors reported in any APVO101 clinical trial or in post-marketing safety surveillance. Since the 
development of inhibitors is correlated with early treatment with factor IX, only subjects with at least 
50 ED of a factor IX treatment will be allowed to participate. Subjects are also tested for inhibitors at 
screening and excluded if positive. Regular inhibitor testing is also done throughout the study. 
Other factor IX class-specific risks include thromboembolic events, hypersensitivity (including 
anaphylaxis) and nephrotic syndrome. None of these adverse events have been seen in APVO101 
clinical trials. There has been one post-marketing report of anaphylaxis in a patient who received 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        27 
 
commercial APVO101 (IXINITY); however, this patient has also reported anaphylaxis with other 
factor IX therapies. This study includes testing of thrombogenic markers at the PK stage to evaluate 
for thrombotic risk. Serum chemistry and urinalysis are tested at Screening and regularly throughout 
the study to evaluate for renal (and other) effects. Subjects with known hypersensitivity to APVO101 
or its excipients are excluded from this study, and subjects are followed frequently, especially during 
the start of the Treatment Phase, to monitor for any adverse events.  
The safety and efficacy data from clinical studies of APVO101, along with its post-marketing safety 
data, support a positive benefit:risk profile for APVO101 for moderately-severe to severe hemophilia 
B patients < 12-years-old. Furthermore, this study is designed to exclude subjects at risk for class-
related adverse events where possible and to monitor the safety of all subjects closely throughout the 
study. 
1.3. 
Clinical Trial Rationale 
The initiation of this study (APVO101-903) is based on safety and efficacy data from two clinical 
trials in previously treated adult, adolescent and pediatric patients with severe hemophilia B. In 
September 2014, the Data and Safety Monitoring Board reviewed the available polished APVO101 
clinical trial safety, immunogenicity and efficacy data from two ongoing clinical trials (IB1001-01 
and IB1001-02) and expressed no concerns, allowing the studies to continue and to recruit new 
subjects <12 years of age. 
APVO101 is licensed in the US (as IXINITY) for control and prevention of bleeding episodes, and 
for perioperative management in hemophilia B patients ≥12 years of age. However, as part of the post-
marketing requirement for APVO101 in the US, the Food and Drug Administration (FDA) has 
requested data in 20 pediatric (< 12 years of age) patients followed-up for 50 ED. In addition, the 
European Medicines Agency (EMA) requires clinical investigation in PTP patients < 12 years of age 
for licensure of recombinant factor IX products for use in children. Currently, the requirements for 
the pediatric development are subject to an agreed Pediatric Investigation Plan (PIP) with the Pediatric 
Development Committee (PDCO) in the EU. 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        28 
 
2. 
TRIAL OBJECTIVES AND PURPOSE 
2.1. 
Primary Objectives 
The following are the primary objectives of APVO101-903: 
• To evaluate safety of APVO101 in pediatric subjects with hemophilia B for at least 50 ED 
• To assess efficacy of APVO101 prophylaxis with respect to prevention of breakthrough 
bleeding and with respect to control of hemorrhaging in pediatric subjects with hemophilia 
B for at least 50 ED 
• To evaluate PK of APVO101 in pediatric subjects with hemophilia B 
• To evaluate APVO101 immunogenicity response (development of inhibitory and 
non-inhibitory factor IX binding antibodies and antibodies to CHOP) 
2.2. 
Exploratory Objectives 
The following are exploratory objectives of APVO101-903: 
• To evaluate markers of thrombogenicity [D-dimer, thrombin-antithrombin III complex 
(TAT) and fragment 1+2 (F1+2)] during the first 24 hours post-infusion of APVO101 
• To evaluate efficacy of APVO101 for perioperative management in pediatric subjects with 
hemophilia B 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        29 
 
3. 
TRIAL DESIGN 
3.1. 
Trial Design 
Study APVO101-903 is a Phase 3/4, single arm, open-label clinical trial. The purpose of the study is 
to evaluate PK, safety, and efficacy of APVO101 prophylaxis in severe or moderately severe 
hemophilia B subjects < 12 years of age. The study is designed to gather information in two age groups 
of previously treated (with a minimum of 50 previous ED to factor IX replacement therapy) pediatric 
patients, specifically those < 6 years of age and 6-12 years of age. 
Study APVO101-903 consists of three distinct phases (Figure 1): 
• PK Phase – PK evaluation will consist of administration of a single 75 ± 5 IU/kg dose, 
followed by factor IX activity and safety assessments up to 50 hours post-infusion. 
• Treatment Phase – subjects will receive APVO101 prophylaxis (starting prophylaxis dose 
to be determined based on APVO101 recovery; ideally within the recommended dose 
range: 35 – 75 IU/kg; twice weekly) for 50 ED (approximately 6 months). 
• Continuation Phase – subjects may continue to receive APVO101 prophylaxis 
(recommended dose range: 35 – 75 IU/kg; twice weekly) for an additional ≥ 50 ED. 
 
 
Figure 1: 
Overview of APVO101-903 Design 
 
 
 
 
 
 
 
 
 
 
The PK evaluation is preceded by a washout period of 4 days or a period of 3 half-lives washout of a 
factor IX product with a prolonged half-life, followed by PK and safety assessments to be completed 
within 50 hours after APVO101 infusion. The Treatment Phase is expected to include a minimum of 
6 months of APVO101 prophylaxis to obtain 50 ED, while the Continuation Phase is expected to 
include APVO101 prophylaxis for an additional ≥ 50 ED (≥ 6 months). Between 15 and 20 evaluable 
subjects are targeted to complete all phases of the study. Treatment with APVO101 to support a 
surgical procedure (if required) is permitted for subjects in Treatment/Continuation phases of the 
study. 
The duration of subject study participation may vary depending on the time of enrollment into the 
study but is expected to be for at least 12 months. 
APVO101 PK Phase 
Treatment Phase 
(prophylaxis) 
50 ED (~6 months) 
Continuation Phase 
(prophylaxis) 
≥ 50 ED (≥ 6months) 
Surgery (if required) 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        30 
 
3.2. 
Anticipated Centers 
Study APVO101-903 is a multi-center trial with international investigational sites; exact locations and 
number of the sites are to be determined. 
3.3. 
Sample Size 
Up to 22 subjects will be enrolled in order to have 15 to 20 evaluable subjects (10 subjects < 6 years 
and 10 subjects 6 to < 12 years) complete the study (i.e., completion of PK assessments and a minimum 
of 50 ED), taking into consideration the very small size of the population available for clinical trials 
and the challenges of these trials in children, especially those under 6 years of age. 
3.4. 
Criteria for Stopping or Terminating the Trial 
Medexus and the principal investigator may elect to terminate the trial early as defined by the clinical 
trial agreement. The trial may be terminated at any or all sites for any of the following reasons: 
• The safety data demonstrate or strongly suggest that the trial treatment (or participation in 
the trial) is unsafe. The investigator and sponsor will be responsible for ongoing review of 
safety data. The investigator will assess seriousness, causality and intensity (severity) of 
an adverse event. 
• The protocol or conduct of the trial is flawed such that the safety or rights of the trial 
subjects may be adversely affected. 
• The ethics committee has withdrawn the approval for the trial and has denied 
reconsideration. 
• The investigational treatment is found to be ineffective. 
• Poor recruitment. 
• Relocation of the investigator or reallocation of investigator’s responsibilities, or 
disqualification of the investigator. 
• Non-adherence to the protocol or unavailability of the principal investigator or his staff for 
the sponsor’s (or their authorized representative) monitoring personnel. 
• Inadequate evidence of the Principal Investigator’s personal conduct or supervision of the 
trial. 
• Change of research strategy or change of management priorities. 
• Imposition of clinical hold by a regulatory authority. 
Any decision to voluntarily suspend or terminate a clinical trial will be carefully reviewed and fully 
justified. The sponsor will notify the FDA and other competent regulatory agencies and the 
Institutional Review Board (IRB)/Ethics Committee (EC) of any suspension or termination, along 
with justification for restarting or terminating the study as applicable. 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        31 
 
The principal investigator must notify the IRB/EC in writing of the trial’s completion or early 
termination. Medexus must receive a copy of the notification letter from the IRB/EC indicating receipt 
of the completion or early termination letter. 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        32 
 
4. 
SELECTION AND WITHDRAWAL OF SUBJECTS 
The study population will consist of subjects who meet study eligibility requirements (inclusion and 
exclusion criteria) outlined in sections below. Eligibility criteria linked to laboratory test results will 
be discerned based on laboratory testing at Screening visit (Section 6.1). A subject will be considered 
‘enrolled’ into the study after receiving first infusion of APVO101. 
4.1. 
Subject Inclusion Criteria 
The following conditions must be met before a subject may be enrolled in the study: 
1. Age: < 11.5 years of age at the time of the first dose and < 12 years throughout the Treatment 
Phase of the study (for at least 50 ED). 
2. Informed consent: subject’s parent or legal guardian written Institutional Review Board 
(IRB)/Ethics Committee (EC)-approved informed consent. An assent form (IRB/EC-approved) 
will be obtained, when required by local regulations/guidelines. 
3. Willingness and ability to make the required study visits and follow instructions while enrolled 
in the study (for at least 50 ED; approximately 6 months). 
4. Documented severe or moderately severe hemophilia B diagnosis (factor IX activity ≤ 2 IU/dL); 
in addition, severity may be indicated by the occurrence of one or more joint bleeding episode(s) 
at any point in the child’s medical history requiring infusion(s) to replace factor IX. 
5. Subjects must be on prophylaxis or switch to a prophylaxis regimen for the duration of the study. 
6. Previously treated patients with a minimum of 50 ED (as documented and determined by the 
investigator) to a preparation/blood components containing factor IX. 
7. Willingness to adhere to the 4-day washout period of any factor IX replacement therapy prior to 
PK evaluation. In case of previous exposure to a factor IX product with a prolonged half-life, a 
washout period of 3 half-lives is required in order to achieve steady state factor IX level prior to 
exposure to APVO101. 
8. Immunocompetent (CD4 count > 400/mm3) and not receiving immune modulating or 
chemotherapeutic agents. 
9. Platelet count at least 150,000/mm3. 
10. Liver function: alanine transaminase (ALT) and aspartate transaminase (AST) ≤ 2 times the 
upper limit of the normal range. 
11. Total bilirubin ≤ 1.5 times the upper limit of the normal range. 
12. Renal function: serum creatinine ≤ 1.25 times the upper limit of the normal range. 
13. Hemoglobin ≥ 7 g/dL. 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        33 
 
4.2. 
Subject Exclusion Criteria 
Any of the following conditions exclude a subject from the study: 
1. History of factor IX inhibitor ≥ 0.6 Bethesda Units (BU); confirmed by the screening result. 
2. Existence of another coagulation disorder. 
3. Evidence of thrombotic disease, fibrinolysis, or disseminated intravascular coagulation (DIC). 
4. Use of an investigational drug within 30 days prior to study entry. 
5. Previous use of APVO101. 
6. Use of medications that could impact hemostasis, such as aspirin. 
7. Known hypersensitivity to the active substance or to any of the excipients in the investigational 
products. 
8. Known allergic reaction to hamster proteins. 
9. History of poor compliance, geographic isolation, unreliable transportation, a serious medical or 
social condition, or any other circumstance that, in the opinion of the investigator, would 
interfere with participation or compliance with the study protocol. 
10. History of adverse reaction to either plasma-derived factor IX or recombinant factor IX that 
interfered with the subject’s ability to treat bleeding episodes with a factor IX product. 
11. History of any medical condition that would impact the efficacy evaluation and/or safety 
evaluation of the study product. 
4.2.1. 
Subject Withdrawal 
The subjects must be available, without coercion, for all parts of the trial. 
If continued participation jeopardizes the subject’s health, the subject should be withdrawn from the 
trial. The investigator is encouraged to consult the sponsor prior to the withdrawal of any subject, 
except in the event of a medical emergency. The reason for withdrawal of any subject must be clearly 
documented on the trial source documents and the appropriate data collection tools. 
4.2.2. 
Subject Withdrawal Criteria 
All subjects are free to withdraw from participation in this trial at any time, for any reason, specified 
or unspecified, and without penalty or loss of benefits to which the subject is otherwise entitled. 
In addition, subjects may be withdrawn from the trial for any of, but not limited to, the following 
reasons: 
• Protocol violation (non-compliance with medication or evaluation schedule with 
impact on subject risk-to-benefit or on protocol integrity) 
• Serious illness that results in subject’s inability to receive therapy or be evaluated per 
protocol requirements 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        34 
 
• Discretion of Principal Investigator 
• Voluntary withdrawal by subject or parent or legal guardian (efforts should be 
made to conduct a termination study visit) 
• Death 
• Sponsor terminates the study 
Reason for withdrawal and the date of withdrawal should be documented. Medexus should be notified 
within 24 hours of all study withdrawals and every effort should be made to conduct an early 
termination evaluation. 
The sponsor reserves the right to terminate the study or withdraw any subject from the study for any 
reason at any time. 
If a subject is withdrawn from the trial, they will not be re-entered into the trial for any reason. 
4.2.3. 
Subject Replacement 
Subjects withdrawn from the trial or who withdraw consent prior to dosing will be replaced. Subjects 
withdrawn from the trial or who withdraw consent after dosing may be replaced.  
Subjects are eligible to be rescreened for a screening failure only if the patient was unable to be 
enrolled during the screening period due to scheduling issues or due to bleeding. Subjects may be 
rescreened up to 3 times for these reasons. 
4.2.4. 
Follow-up for Withdrawn Subjects 
Every attempt will be made to ensure that subjects who are withdrawn, or who withdraw from the trial 
during the active treatment or follow-up period, will complete all safety and available efficacy 
assessments for the early withdrawal visit as outlined in this protocol. The investigator should inform 
the subjects and/or parent or legal guardian that these assessments are for their own safety. 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        35 
 
5. 
TRIAL MEDICATION 
APVO101 is a lyophilized coagulation factor IX (recombinant) for IV administration.  
5.1. 
Packaging and Formulation 
APVO101 is available in single-use vials containing the labeled amount of factor IX activity. 
APVO101 is formulated as a sterile, nonpyrogenic, lyophilized powder that is reconstituted with 
sterile WFI. After reconstitution of the lyophilized powder the concentrations of excipients are 10 mM 
histidine, 3% mannitol, 1% trehalose, 66 mM NaCl, and 0.0075% Tween-80, pH 6.8. There are no 
novel excipients in the formulation of APVO101 drug product and there are no particular concerns 
related to any of the ingredients for use in the pediatric population. 
For more information, please refer to the current version of Investigator’s Brochure for APVO101. 
5.2. 
Labeling 
APVO101 vial labels and shelf cartons will include information to comply with local regulations for 
the country in which the trial is conducted, in the appropriate language(s). 
An example of information that may be included on vial label/shelf carton for APVO101: 
• “Investigational Drug”, “To Be Used by Qualified Investigator Only”, “Caution: New 
Drug - Limited by Federal Law to Investigational Use” or similar wording 
• The product strength/potency 
• The lot number 
• The date of manufacture and/or Expiry date 
• The protocol code or identification 
• The recommended storage conditions 
• The name and address of the Manufacturer 
5.3. 
Storage Conditions 
APVO101 vials must be stored and transported at 2°C – 8°C. Do not freeze. Keep the APVO101 vials 
away from light. 
Reconstituted APVO101 vials should not be refrigerated and must be used within 3 hours of 
reconstitution. The reconstituted APVO101 product must be at room temperature at time of infusion. 
For further information, refer to the current version of Investigator’s Brochure for APVO101. 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        36 
 
5.4. 
Preparation and Administration 
APVO101 is prepared by reconstituting lyophilized powder with sterile WFI. APVO101 reconstituted 
product must be at room temperature at time of infusion. Administration should occur at a maximum 
infusion rate of 10 mL/minute; product should be infused over a period of approximately five minutes. 
Reconstitution and administration instructions for APVO101 are provided in the most current 
Investigator’s Brochure for APVO101. 
Site personnel will train the subject and/or parent or legal guardian on reconstitution and 
administration of APVO101 and assure that the subject and/or parent or legal guardian understands 
and is able to demonstrate the procedure. The instructions on how to reconstitute and administer the 
study drug will be provided to the subjects and parent or legal guardians. 
5.5. 
Medication Shipment 
APVO101 will be shipped to the site at a temperature of 2°C – 8°C. During shipment, the temperature 
of the drug will be monitored to ensure the required temperature conditions are maintained. The 
principal investigator or designate will be responsible for checking the number of vials and the 
condition of the vials received and entering this information into the drug accountability records, 
reporting the condition to Medexus and returning the data logger and all required documentation. Drug 
will be released for use by the site only after the data logger results are reviewed and written 
authorization has been issued to the Investigator/designate by the sponsor or designate. At the end of 
the trial, or upon request of the sponsor, all unused, partially used or empty vials will be returned to 
the sponsor or destroyed at the site as directed by Medexus. 
5.6. 
Drug Accountability 
The investigator is responsible for maintaining accurate inventory records of APVO101. The 
investigator or designate will inventory all APVO101 shipments upon receipt, acknowledge 
possession by signing all required documentation, and returning these to the sponsor. The investigator 
must ensure that all drug supplies are kept in a secure location in the site pharmacy in accordance with 
recommended storage conditions. A research pharmacist or a designated individual will maintain a 
current inventory and ongoing record of APVO101 using the Drug Accountability Form provided by 
the sponsor. This inventory record for the APVO101 will include: 
• Protocol name, number and sponsor 
• Product name and description 
• Trial site and investigator name 
• Product lot number and date of manufacture and/or Use-by/Expiry/Re-test date 
• Number of vials dispensed, date and time of dispensing and study subject for whom 
product was dispensed 
• Product balance 
• Name and title of qualified individual dispensing product. 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        37 
 
Subjects and/or their parent or legal guardian are instructed to return all used vials to the study site. 
An accounting of all returned and non-returned vials will be ongoing and will be noted on the Drug 
Accountability Form. 
These records will be reviewed by representatives of the sponsor and may be reviewed by regulatory 
agencies. 
5.7. 
APVO101 Dosing 
5.7.1. 
Dose and Schedule 
PK Phase 
For the initial PK evaluation and after a 4-day washout period from previous factor IX replacement 
therapy or 3 half-lives washout of a factor IX product with a prolonged half-life, a member of the 
investigational site staff will administer a single IV 75 ± 5 IU/kg dose of APVO101. 
Treatment Phase 
After completion of PK Phase assessments, subjects will be treated with a prophylaxis regimen of 
APVO101. Subjects will receive a single IV dose of APVO101 twice weekly or at a frequency of 
infusions as determined appropriate by the investigator for the particular study subject for a total of 
50 ED. The starting prophylaxis dose will be based on APVO101 recovery from PK Phase assessments 
(only pre-infusion and 15-30 minute post-infusion samples); ideally within the recommended dose 
range: 35 – 75 IU/kg, twice weekly). Samples for APVO101 recovery (only pre-infusion and 15-30 
minutes post-infusion from the PK assessment) will be processed by the local laboratory and tested 
by the central laboratory. In the event the central laboratory is unable to provide the PK data in time 
to calculate the starting prophylaxis dose, the dosage and administration instructions found in the 
package insert for the U.S. approved product (IXINITY) should be followed. Once PK data are 
available, the prophylaxis dose may be adjusted if needed. 
Refer to the Dosage and Administration section in the package insert and Pharmacy Manual for more 
information.  
For treatment and control of breakthrough, spontaneous or trauma-related bleeding episodes, the dose 
should be based on severity of bleeding episodes; see below: 
• Minor bleeding episodes [e.g., uncomplicated hemarthroses and superficial muscle (except 
iliopsoas) with no neurovascular compromise, other soft tissue bleeds] and/or moderate 
bleeding episodes (e.g., hemarthrosis of longer duration, recurrent hemarthrosis, mucous 
membranes, deep lacerations, hematuria): 40 – 60 IU/kg 
• Major or life-threatening bleeding episodes (e.g., iliopsoas, deep muscle with 
neurovascular injury, substantial blood loss, central nervous system, pharyngeal, 
retropharyngeal, retroperitoneal): 60 – 100 IU/kg 
During APVO101 prophylaxis treatment and/or APVO101 treatment for control and management of 
bleeding episodes, every effort will be made to ensure that the prescribed dose per kilogram body 
weight is given. However, since it may be difficult to determine fractions of a vial for purposes of 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        38 
 
providing an exact dose, it is acceptable to round up or down to the nearest vial. The process of 
rounding up or down should not, however, result in the study subject receiving > 120% or < 90% of 
the prescribed dose. The exact amount of factor IX infused must be recorded. 
Continuation Phase 
Following completion of the Treatment Phase (i.e., 50 ED), the investigator will assess the subject’s 
dose and either assign the most recent dose from Treatment Phase or modify the dose if clinically 
indicated (see Section 5.7.2). The Continuation Phase dose should be within the recommended dose 
range of 35 – 75 IU/kg, twice weekly. 
For treatment and control of breakthrough, spontaneous or trauma-related bleeding episodes, the dose 
should be based on severity of bleeding episodes; see below: 
• Minor and/or moderate bleeding episodes: 40 – 60 IU/kg 
• Major or life-threatening bleeding episodes: 60 – 100 IU/kg 
Surgery 
In the event of a minor or major surgery during the course of study participation (Treatment/ 
Continuation phases), use of either bolus or continuous infusion of APVO101 for surgical coverage 
is permissible. 
Examples of major surgical procedures include synovectomy, knee or hip replacement, total tooth 
extraction, tonsillectomy and/or adenoidectomy, surgery for intracranial hemorrhage, radial head 
excision, arthrodesis, ankle surgery, abdominal surgery, herniorrhaphy, or surgery for major muscle 
bleed management. The following dosing is recommended for major surgical procedures: 
• If using bolus infusions, an infusion of up to 120 IU/kg will be given within 1 hour prior 
to the start of the procedure, followed by an infusion of approximately 60 IU/kg 12 hours 
after the first infusion, and up to 120 IU/kg 24 hours after the first infusion, depending on 
the subject’s post-infusion factor IX activity. This regimen of bolus infusions will continue 
every 12 hours as long as the physician and surgeon deem necessary, but for a minimum 
of 3 days post-procedure for major surgery or a minimum of 1 day post-procedure for 
minor surgery. 
• If administering a continuous infusion, it will also continue for a minimum of 3 days post-
procedure for major surgery or a minimum of 1 day post-procedure for minor surgery. The 
infusion rate, dose and timing of subsequent infusions and adjustments in dosing will be 
recorded and guided by factor IX assay results, with the doses of APVO101 administered 
appropriately to ensure that the plasma factor IX level does not drop below 60%. If 
continuous infusion is used, the plasma level of factor IX should range between 70% and 
110%. 
5.7.2. 
Dose Modifications 
If clinically indicated, more or less frequent infusions or a variation of the recommended dose may be 
prescribed at the discretion of the investigator. The decision to do so will be based upon a host of 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        39 
 
determinants, including pre- and/or post-dose Factor IX activity, type and severity of the bleeding 
episode, occurrence of an injury, timing of the infusion relative to the onset of bleeding, degree of 
pain, swelling and disability at the site, dosage of and clinical response to the first infusion, follow-up 
infusion(s) given, timing of the follow-up infusion(s), re-injury, or injury at a previous site of bleeding 
such as a target joint. Pre- and post- APVO101 infusion factor IX activity (i.e., APVO101 recovery) 
are recommended (when feasible) to determine dose modifications. The precise reason for doing so 
must be recorded in the case report form (CRF). 
5.7.3. 
Treatment Compliance 
PK Phase, Surgery (if required): 
Because APVO101 treatment will be administered intravenously in a clinical setting for PK 
assessments and during surgical procedure(s), compliance with treatment is not expected to be an 
issue. However, it will be important during the washout period for the subject and within the 50-hour 
period post-PK APVO101 infusion to refrain from using factor IX products unless it is necessary to 
treat a bleeding episode. In such a case, the washout period will be re-started after the last infusion for 
treating the bleeding episode has been administered. Use of a non-study factor IX product is not 
permitted; however, if such an instance occurs, the details, including product name, dose, and reason 
for use, are to be documented. 
Treatment Phase and Continuation Phase 
Throughout the study, subjects/subjects’ parents or legal guardians will maintain a diary of bleeding 
episodes, including usage (compliance) and tolerance of APVO101. In addition, subjects/subjects’ 
parents or legal guardians will be asked to account for all used vials (i.e., return all vials to the site). 
The subjects/subjects’ parents or legal guardians will be asked to record AEs and concomitant 
medications between visits. An evaluation of efficacy will also be recorded. Use of a non-study factor 
IX product is not permitted; however, if such an instance occurs, the details, including product name, 
dose, and reason for use, are to be documented. 
The investigator or study coordinator will review the diary with the study subject/subject’s parents or 
legal guardians at each visit. This collaborative review is intended to identify treatment-related 
problems, to evaluate compliance, and to reinforce adherence to the prophylaxis regimen. 
Additionally, during this diary review, site staff will reinforce the importance of complete 
documentation. 
The study protocol specifies that each study subject will receive APVO101 on a prophylaxis schedule. 
In the event that this schedule is not followed, documentation of the reasons and circumstances 
altering the schedule will be recorded. In the event that the subject, his parent or legal guardian, or 
treating physician changes the prophylaxis regimen including one of ‘on demand therapy’, details of 
each bleed and response to APVO101 treatment will be recorded. In addition, the reasons for changing 
the prophylaxis schedule or changing to ‘on demand therapy’ will be recorded. 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        40 
 
6. 
TRIAL PROCEDURES 
6.1. 
Screening (21 to 5 days prior to PK Phase)  
Eligible subjects and their parent or legal guardian will first undergo informed consent counselling. 
Once informed consent and assent (as applicable) have been obtained from subjects and parent or legal 
guardian, subjects will undergo a screening visit to ascertain their eligibility in this trial. The screening 
visit assessments will include: 
1. Signed and dated Informed Consent Form (ICF) and assent form (as applicable) 
2. Inclusion/exclusion criteria review. 
3. Medical and hemophilia-related history, including documentation of factor IX genotype mutation, 
bleeding episode(s), documentation of PK data (e.g., recovery and half-life) utilizing prior 
non-study factor IX therapy, and documentation of at least 50 ED of factor IX replacement 
therapy 
4. Concomitant medications 
5. Demographics (age, sex) 
6. Physical exam, vital signs, body weight and height 
7. Local laboratory assessments: 
a. Serum chemistry [ALT, AST, alkaline phosphatase (ALP), blood urea nitrogen (BUN) 
or urea, uric acid, creatinine, total bilirubin, and glucose] 
b. Complete blood count (CBC) with differential [hemoglobin, hematocrit, absolute 
counts and/or percent of: white blood cells, neutrophils, monocytes, lymphocytes, 
eosinophils, basophils, platelets and red blood cells; mean platelet volume (MPV), 
mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH) and mean 
corpuscular hemoglobin concentration (MCHC)] 
c. CD4 count 
d. Urinalysis [urine dipstick, followed by microscopy if abnormal] 
8. Central laboratory assessments: 
a. Inhibitory factor IX antibodies (Nijmegen modified Bethesda assay) 
b. Non-inhibitory factor IX binding antibodies 
c. Anti-CHOP antibodies 
9. Review of subject diary of previous factor IX therapy (if available): infusions, bleeding 
summary, subject’s efficacy assessment, adverse events, and concomitant medications. 
10. Investigator’s assessment of efficacy of previous factor IX therapy 
11. Assessment of major and target joint(s) 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        41 
 
12. Assessment of adverse events  
13. Review of study requirements, subject diary instructions, and training on APVO101 
reconstitution and administration 
6.2. 
Pharmacokinetic (PK) Phase Assessments 
After a 4-day washout of factor IX replacement therapy or 3-half-lives washout of a factor IX product 
with a prolonged half-life, the following assessments will be evaluated. Given pediatric blood volume 
limitations, the number and timing of thrombogenicity marker assessments varies by subject weight 
(see Table 2). 
Pre-infusion (2 hours to 15 minutes prior to infusion) 
1. Physical exam, vital signs, body weight, height, concomitant medications, updated medical 
history (if applicable) 
2. Central laboratory assessments: 
a. Inhibitory factor IX antibodies (Nijmegen modified Bethesda assay: for subjects 
weighing > 28 kg) 
b. Non-inhibitory factor IX binding antibodies (for subjects weighing > 28 kg) 
c. Anti-CHOP antibodies (for subjects weighing > 28 kg) 
d. Factor IX activity 
e. Thrombogenicity markers (See Table 2) 
Post-infusion (75 ± 5 IU/kg) 
1. Central laboratory assessments: 
a. Factor IX activity at the following time points post-infusion: 15-30 minutes, 4-6 hours, 
24-26 hours and 46-50 hours 
b. Thrombogenicity markers [D-dimer, thrombin:antithrombin (TAT) complex and 
fragment 1+2] at 15-30 minutes, 4-6 hours and 24-26 hours 
post-infusion                 
(See Table 2) 
2. Vital signs at each PK time-point post-infusion 
3. Assessment of adverse events 
Note: pre-infusion and 15-30 minute post-infusion samples will be tested for factor IX activity to 
determine starting prophylaxis dose. See section 5.7.1 for further details. 
6.3. 
Treatment Phase Assessments 
After the start of APVO101 prophylaxis treatment regimen, the following assessments will be 
performed at: 
5 ED (± 1 ED) and 12 ED (± 2 ED) 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        42 
 
1. Central laboratory assessments: 
a. Inhibitory factor IX antibodies (Nijmegen modified Bethesda assay) 
b. Non-inhibitory factor IX binding antibodies 
c. Anti-CHOP antibodies 
d. Mutation genotyping (12 ED visit only, if not documented); for patients below 10 kg 
this may be done at any time during the study when blood volumes allow 
2. Review of subject diary: infusions, bleeding summary, subject’s efficacy assessment, adverse 
events, concomitant medications and compliance 
3. Concomitant medications 
4. Assessment of adverse events 
5. Investigator’s assessment of efficacy 
25 ED (± 3 ED) and 50 ED (± 5 ED) 
1. Physical exam, vital signs, body weight, and height 
2. Concomitant medications 
3. Local laboratory assessments: 
a. Serum chemistry (for patients below 17 kg, collect if blood volumes allow) 
b. Complete blood count (CBC) with differential (for patients below 17 kg, collect if 
blood volumes allow) 
c. Urinalysis [urine dipstick, followed by microscopy if abnormal] 
4. Central laboratory assessments: 
a. Inhibitory factor IX antibodies (Nijmegen modified Bethesda assay) 
b. Non-inhibitory factor IX binding antibodies 
c. Anti-CHOP antibodies 
5. Review of subject diary: infusions, bleeding summary, subject’s efficacy assessment, adverse 
events, concomitant medications and compliance 
6. Assessment of adverse events 
7. Investigator’s assessment of efficacy 
8. Assessment of major and target joints (50 ED only) 
6.3.1. 
Surgery Assessments 
Treatment with APVO101 to support a minor or major surgical procedure (if required) is permitted 
for subjects in Treatment Phase. The following assessments will be performed for surgical 
procedure(s): 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        43 
 
Prior to surgery; pre-infusion (2 hours to 15 minutes before infusion) 
1. Documentation of planned surgery including rationale (may occur at any time prior to surgery) 
2. Surgeon’s assessment of expected/estimated blood loss for the surgical procedure (may occur 
at any time prior to surgery) 
3. Local laboratory assessment: 
a. Factor IX activity 
4. Central laboratory assessments: 
a. Factor IX activity (if blood volumes allow) 
5. Vital signs 
Prior to surgery; 5 – 30 minutes post-infusion (bolus) 
1. Local laboratory assessment: 
a. Factor IX activity 
2. Central laboratory assessment: 
a. Factor IX activity (if blood volumes allow) 
3. Assessment of adverse events 
During surgery 
1. If study product is infused during surgery, local laboratory assessment 
a. Factor IX activity pre- and post-dose (5-30 minutes) 
2. Assessment of adverse events 
3. Use of blood products 
End of surgery 
1. Surgeon’s assessment of total blood loss for the surgical procedure 
2. Assessment of adverse events 
3. Use of blood products 
Post-surgery 
12 hours (±2 hours) post-initial infusion; pre-infusion 
1. Local laboratory assessment: 
a. Factor IX activity 
2. Central laboratory assessment: 
a. Factor IX activity (if blood volumes allow) 
3. Vital signs 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        44 
 
4. Surgeon’s assessment of blood loss 
5. Use of blood products 
12 hours post-initial infusion (±2 hours); 5 – 30 minutes post-infusion (bolus) 
1. Local laboratory assessment: 
a. Factor IX activity 
2. Central laboratory assessment: 
a. Factor IX activity (if blood volumes allow) 
3. Assessment of adverse events 
24 hours post-initial infusion (±3 hours); pre-infusion 
1. Local laboratory assessment: 
a. Factor IX activity 
2. Central laboratory assessment: 
b. Factor IX activity (if blood volumes allow) 
3. Vital signs 
4. Surgeon’s assessment of blood loss 
5. Use of blood products 
24 hours post-initial infusion (±3 hours); 5 – 30 minutes post-infusion (bolus) 
1. Local laboratory assessment: 
a. Factor IX activity 
2. Central laboratory assessment: 
a. Factor IX activity (if blood volumes allow) 
3. Assessment of adverse events 
Factor IX activity (local laboratory assessment) should be monitored every 12 hours (±2 hours) 
thereafter (for a minimum of 3 days post-surgery or until healing in case of a major surgery or a 
minimum of 1 day post-procedure for minor surgery). Factor IX activity should be assessed before 
and within 30 minutes post-infusion of study product. If blood volumes allow, Factor IX activity 
should also be assessed by central laboratory at each timepoint. Adjustments in APVO101 dosing and 
timing post-surgery of each adjustment should be documented. Adverse events should be assessed for 
the duration of each continuous infusion period (±2 hours). 
For continuous infusions, factor IX activity (local laboratory assessment), assessment of vital signs 
and use of blood products (pre-infusion) should be performed at 12-hour (±2 hours) and 24-hour 
(±3 hours) time points post-surgery and subsequently on a daily basis or more frequently if needed 
until continuous infusion is discontinued. If blood volumes allow, Factor IX activity should also be 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        45 
 
assessed by central laboratory at each timepoint. Adjustments in APVO101 dosing and timing 
post-surgery of each adjustment should be documented. Adverse events should be assessed for the 
duration of each continuous infusion period (±2 hours). 
In case of a major surgery (supported by bolus or continuous infusions), surgeon’s assessment of blood 
loss should be performed every 12 hours (±2 hours) for at least 3 days post-surgery or until healing (if 
applicable). 
28 days (±7 days) post-factor IX replacement therapy for surgery 
1. Use of blood products 
6.4. 
Continuation Phase Assessments 
Treatment with APVO101 beyond 50 ED (accumulated during the Treatment Phase) will constitute 
Continuation Phase treatment. 
Following 50 ED visit, subjects will be assessed at 75 ED (± 5 ED), 100 ED (± 5 ED) and every 
3 months (~25 ED ± 5 ED) thereafter until end of study (note: subjects may continue on study until 
last-subject-in completes 100 ED visit) for the following: 
1. Physical exam, vital signs, body weight and height 
2. Concomitant medications 
3. Local laboratory assessments: 
a. Serum chemistry (for patients below 17 kg, collect if blood volumes allow) 
b. Complete blood count (CBC) with differential (for patients below 17 kg, collect if 
blood volumes allow) 
c. Urinalysis [urine dipstick, followed by microscopy if abnormal] 
4. Central laboratory assessments: 
a. Inhibitory factor IX antibodies (Nijmegen modified Bethesda assay) 
b. Non-inhibitory factor IX binding antibodies 
c. Anti-CHOP antibodies 
5. Review of subject diary: infusions, bleeding summary, subject’s efficacy assessment, adverse 
events, concomitant medications and compliance 
6. Assessment of adverse events 
7. Investigator’s assessment of efficacy 
8. Assessment of major and target joints (100 ED only) 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        46 
 
6.4.1. 
Surgery Assessments 
Treatment with APVO101 to support a minor or major surgical procedure (if required) is permitted 
for subjects in Continuation Phase. Refer to Section 6.3.1 for assessments to be performed for surgical 
procedure(s). 
6.5. 
End of Study or Early Withdrawal Assessments 
At the end of the study, or for subjects who prematurely terminate or who are withdrawn before the 
study is complete, the following will be evaluated: 
1. Physical exam, vital signs, body weight and height 
2. Concomitant medications 
3. Assessment of adverse events 
4. Local laboratory assessments: 
a. Serum chemistry (for patients below 17 kg, collect if blood volumes allow) 
b. CBC with differential (for patients below 17 kg, collect if blood volumes allow) 
c. Urinalysis [urine dipstick, followed by microscopy if abnormal] 
5. Central laboratory assessments: 
a. Inhibitory factor IX antibodies (Nijmegen modified Bethesda assay) 
b. Non-inhibitory factor IX binding antibodies 
c. Anti-CHOP antibodies 
6. Review of subject diary: infusions, bleeding summary, efficacy assessment, adverse events, 
concomitant medications and compliance 
7. Investigator’s assessment of efficacy 
8. Assessment of major and target joints 
6.6. 
Handling of Samples 
Refer to the APVO101-903 Laboratory Manual on how to handle samples for central laboratory 
analyses during each phase of the study. Local laboratory samples should be handled by site standard 
procedures. 
6.7. 
Shipment of Samples 
Refer to the APVO101-903 Laboratory Manual on how to ship samples for central laboratory analyses 
during each phase of the study. Local laboratory samples should be transported according to site 
standard procedures. 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        47 
 
6.8. 
Concomitant Medications 
Any medication taken by the subject, including herbal preparations and non-prescription medications, 
within 15 days prior to screening and during the course of the trial and the reason for concomitant 
medication use, will be recorded on the trial source documents and concomitant medications page of 
the CRF. 
6.9. 
Excluded Concomitant Medications 
The following treatments are not permitted during the study: 
• Agents impacting the hemostatic system (e.g., aspirin) 
• Immunosuppressive drugs (e.g., steroids such as prednisone, chemotherapeutic agents) 
• All other factor IX therapies (e.g., plasma-derived or recombinant factor IX products) 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        48 
 
7. 
ASSESSMENT OF APVO101 PHARMACOKINETICS 
Factor IX concentration levels are the basis for all PK parameter calculations. 
Incremental recovery will be determined, as will the maximum plasma concentration (Cmax) and the 
half-life (t1/2). The area under the concentration time curve from time 0 to infinity (AUC0-∞) will be 
determined by the trapezoidal rule and the clearance (Cl) and volume of distribution at steady-state 
(Vdss) will be calculated from this number. Refer to Section 11.2.1 for PK endpoints. 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        49 
 
8. 
ASSESSMENT OF APVO101 EFFICACY 
8.1. 
Subject’s Assessment of Efficacy 
Throughout the study, subjects and/or their parent or legal guardian will maintain a subject diary to 
record information about each APVO101 infusion, any AEs and all bleeding episodes (trauma or 
spontaneous). An assessment of efficacy will be made for each bleeding episode. In the event of 
trauma, details will be recorded. 
Within 6 hours (exact time to be recorded) after the subject believes the bleeding has stopped, an 
overall evaluation of efficacy of treatment will be provided. This will be done using the following 
verbal descriptors: 
• Excellent: a dramatic response with abrupt pain relief and clear reduction in joint or 
hemorrhage site size 
• Good: pain relief or reduction in hemorrhage site size that may have required an additional 
infusion for resolution 
• Fair: probable or slight beneficial response usually requiring one or more additional 
infusions for resolution 
• Poor: no improvement or condition worsens 
In addition to the description of efficacy, the subject and/or their parent or legal guardian will indicate 
the following: 
• How long it took the bleeding to stop 
• How long it took the pain to stop 
• How long it took the swelling (if present) to resolve 
This will be done for each variable using a series of check boxes for time intervals ranging from 
< 2 hours to 72+ hours after the onset of the bleeding episode. 
The study investigator will be contacted by the subject, if efficacy of two consecutive APVO101 
infusions is rated as ‘fair’ or ‘poor’. The subject will be instructed to call the treatment center if there 
is an occurrence of ‘poor’ or no response to the therapy (i.e., sub-optimal response; see Section 8.2) 
for a specific bleeding episode. 
The subjects and/or their parent or legal guardian will document in the diary if no bleeding episodes 
occurred. 
8.2. 
Investigator’s Assessment of Efficacy 
At each study visit [during Treatment Phase and Continuation Phase; see Table 1], the investigator 
will make an assessment of APVO101 prophylaxis efficacy and an assessment of efficacy for control 
of bleeding episodes [if bleeding episode(s) are reported by the subject and/or their parent or legal 
guardian during the period]. The assessment will be based on the recording of events in the diary (i.e., 
review of subject diary) and discussion with the study subject and/or their parent or legal guardian. 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        50 
 
The investigator will indicate the overall assessment of APVO101 prophylaxis efficacy, considering 
the absence of bleeding episodes, site, severity and types of bleeding episodes treated, and other factors 
that might influence the therapeutic response. In addition, when bleeding episode(s) are reported by 
the subject and/or their parent or legal guardian, the investigator will also rate the APVO101 efficacy 
for control and management of bleeding episode(s) treated. The investigator will consider the site, 
severity and type of the bleeding episodes reported by the subject and/or their parent or legal guardian 
when evaluating efficacy of APVO101 for control and management of bleeding episodes. 
The investigator’s efficacy assessment categories for prophylaxis and control of bleeding episodes 
will include: ‘effective’, ‘partially effective’ and ‘not effective’. 
If, in the estimation of the investigator, the response has been sub-optimal (i.e., an occurrence of ‘poor’ 
or ‘no response’ to the therapy for a specific bleeding episode as reported by the subject and/or their 
parent or legal guardian), this will be recorded and the reason for this assessment will be specified. In 
such an event (sub-optimal response), the investigator will review the circumstances surrounding the 
bleed and its response to therapy. Information collected shall include the following: 
• Site of the bleed 
• Cause and extent of injury 
• Past history of bleeds at the anatomical site (determined by the investigator from subject’s 
medical and hemophilia-related history and from the review of subject’s diary while on 
study) 
• Relevant clinical issues at the site for that bleed (e.g., in the case of a joint bleed, if the 
joint is a target joint, the extent of pain, joint swelling, and dysfunction over time 
(determined by the investigator from subject’s medical and hemophilia- related history) 
• Specifics of the management administered to that point 
If a sub-optimal response to treatment is observed in two separate bleeding episodes in the same 
subject over the course of the study, this will be reported as an AE, although the investigator will have 
the option of reporting a sub-optimal response to one bleed as an AE. 
In the case of a sub-optimal response, the investigator is encouraged to perform a test for inhibitory 
factor IX antibodies and APVO101 recovery (75 ± 5 IU/kg; factor IX measurements pre-infusion and 
at 15-30 minutes post-infusion). Samples for APVO101 recovery determination will be processed 
locally and tested locally and by the central laboratory. 
The test for inhibitory factor IX antibodies will be completed locally and by the central laboratory. A 
repeat test will be performed by the central laboratory in case of a positive inhibitor test result by the 
central laboratory within 2 weeks of the study site notification of the original positive local laboratory 
result. Subjects who develop an inhibitor that changes from a low (≤ 5 BU) to a high titer (> 5BU) 
inhibitor or from a high titer to a low titer upon a second evaluation should return to the study site 
within two weeks of the second inhibitor assessment, for a third inhibitor test with a suggested 
minimum wash-out period of 72 hours. Once a low (0.6 to 5 BU) or a high titer (> 5 BU) inhibitor is 
confirmed, the subject will be withdrawn from the study. Any inhibitor confirmed by the central 
laboratory must be reported as a serious adverse event (SAE). 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        51 
 
8.3. 
Surgeon’s Assessment of Efficacy 
APVO101 will be evaluated for success in providing coverage for surgical procedures (if required 
during Treatment/Continuation phases of the study). This will be assessed by the surgeon as follows: 
• Estimation of expected blood loss prior to surgery (prior to infusion of APVO101), and 
actual blood loss during surgery, at the end of surgery, 12 hours and 24 hours post- surgery 
or every 12 hours for at least 3 days post-surgery or until healing in case of a major surgery, 
as ‘less than expected’, ‘expected’, or ‘more than expected’ 
• Estimation of blood loss post-surgery at 12 hours and 24 hours post-surgery or every 
12 hours for at least 3 days post-procedure or until healing in case of a major surgery, as 
‘hemostasis superior’, ‘hemostasis adequate’, or ‘hemostasis poorly controlled’ 
The surgeon will estimate the expected blood loss at the time of surgery (prior to infusion of 
APVO101) by taking into consideration the planned surgical procedure in a hemostatically normal 
male individual of the same demographics as the study subject for the intra-operative period, and, if 
applicable, for the post-operative period until drain removal and/or healing. 
During the surgery, the surgeon should evaluate blood loss as per standard of care for the surgical 
procedure and the discretion of the surgeon. 
At the end of the surgery, the surgeon will assess total blood loss for the surgical procedure and record 
the use of blood products for the duration of the surgical procedure (if applicable). 
The use of and volume of blood products during the perioperative period (first 24 hours) and during 
the healing phase (see Table 3) will be recorded as an indicator of APVO101 hemostatic efficacy. 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        52 
 
9. 
ASSESSMENT OF SAFETY 
Safety throughout the clinical trial will be evaluated by assessment of the following: 
• Adverse events (AEs) 
− All AEs will be reported by investigators and subjects and/or their parent or legal 
guardian. AEs are to be elicited by the investigator (or designate) asking the subject 
and/or their parent or legal guardian non-leading questions. Subjects and/or their parent 
or legal guardian will record AEs in the subject diary and the information will be 
reviewed by the investigator during each scheduled visit. 
• Physical exams 
• Vital signs (pulse rate, blood pressure, respiratory rate and temperature) 
• Laboratory assessments, including: 
− Thrombogenic markers (D-dimer, TAT complex and fragment 1+2)  
− Serum chemistry (ALT, AST, ALP, BUN or urea, uric acid, creatinine, total bilirubin 
and glucose) 
− CBC with differential [hemoglobin, hematocrit, absolute counts of: white blood cells, 
neutrophils, monocytes, lymphocytes, eosinophils, basophils, platelets and red blood 
cells; mean platelet volume (MPV), mean corpuscular volume (MCV), mean 
corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration 
(MCHC)] 
− Urinalysis [urine dipstick, followed by microscopy if abnormal] 
− Immunogenicity (inhibitor titer, non-inhibitory factor IX binding antibodies, and anti-
CHOP antibodies) 
Any clinically significant changes (as determined by the investigator) in laboratory test results, vital 
signs or physical exam must be captured as adverse events. 
The above listed safety assessments will be evaluated at pre-determined time points during the conduct 
of the trial (see Table 1 and Table 3). 
The central laboratory will create a distribution of values for all three thrombogenic markers (D-dimer, 
TAT complex, and fragment 1+2) based on negative controls (human plasma). The cut-off point for 
positivity will be defined as any value beyond the 99th percentile of the distribution of values for the 
negative controls for that particular parameter. 
9.1. 
Definitions of Adverse Event, Serious Adverse Event and Adverse Drug 
Reaction 
The occurrence of AEs, serious AEs (SAEs) and adverse drug reactions (ADRs) will be monitored 
throughout all phases of the trial and will cover all participating subjects. The definitions for AE, SAE 
and ADR are provided in Section 9.1.1, Section 9.1.2 and Section 9.1.3, respectively. 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        53 
 
The relationship and relatedness of the AE to APVO101 is to be judged by the investigator as defined 
in Section 9.2.2. 
9.1.1. 
Definition of an Adverse Event 
An adverse event (AE) is defined as any untoward, undesirable, or unintended medical occurrence in 
a clinical trial subject administered APVO101 which does not necessarily have a causal relationship 
with APVO101. For purposes of this clinical trial, an AE can therefore be any unfavorable and 
unintended sign (e.g., including an abnormal laboratory finding), symptom, or disease temporally 
associated with the use of APVO101, whether or not related to the product. 
Examples of an AE include: 
• Exacerbation of a chronic or intermittent pre-existing condition, including either an 
increase in frequency or intensity of the condition 
• Significant or unexpected worsening or exacerbation of the condition/indication under 
study (hemophilia B) 
• A new condition detected or diagnosed after study product administration even though it 
may have been present prior to the start of the study 
• Signs, symptoms, or clinical sequelae of a suspected overdose of either study product or a 
concurrent medication (“overdose” per se, should not be reported as an AE) 
• Pre- or post-treatment events that occur as a result of protocol-mandated procedures (e.g., 
invasive protocol-defined procedures, modification of a subject’s previous drug treatment 
regimen) 
• A sub-optimal response to APVO101 treatment observed in two separate bleeding episodes 
in the same subject over the course of the study; although, the investigator will have the 
option of reporting a sub-optimal response to one bleed as an AE. 
• A thromboembolic event (TEE) 
• Nephrotic syndrome 
• Hypersensitivity reaction, allergic reaction, anaphylaxis, anaphylactic shock; including, 
but not limited to symptoms of difficulty breathing, shortness of breath, swelling, hives, 
generalized urticaria, tightness of the chest, bronchospasm, laryngospasm, wheezing, 
hypotension, blurred vision 
• Severe anaphylaxis; symptoms may include severe hives, severe swelling, severe chest 
tightness, difficulty breathing, wheezing, faintness, rapid heart rate, and low blood pressure 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        54 
 
An AE does not include: 
• Medical or surgical procedures (e.g., colonoscopy or biopsy); the medical condition that 
leads to the procedure is an AE 
• Social or convenience hospital admissions where an untoward medical occurrence did not 
occur 
• Day-to-day fluctuations of a pre-existing disease or conditions present or detected at the 
start of the study that do not worsen 
• The disease/disorder being studied (hemophilia B), or expected progression, signs, or 
symptoms of the disease/disorder being studied (e.g., bleeding episodes) unless more 
severe than expected for the subject’s condition 
All AEs that occur after informed consent/assent is signed will be recorded in the source documents 
and on the appropriate CRF page. 
In addition, all hypersensitivity and allergic reactions, anaphylaxis, and/or anaphylactic shock 
reactions will be recorded on the APVO101 Hypersensitivity Reaction Reporting Form; this form will 
be transmitted to Medexus Pharmacovigilance within 24 hours of the occurrence using the contact 
information below: 
Email: safetydesk@psi-cro.com 
The information to be collected includes the nature, date and time of onset, intensity, duration, 
causality, and outcome of the event. Even if the AE is assessed by the investigator as not reasonably 
attributable to APVO101, its occurrence must be recorded in the source documents and on the 
appropriate page of the CRF. 
Treatment-emergent AEs will be defined as AEs that occur after the first infusion with APVO101. 
9.1.2. 
Definition of a Serious Adverse Event 
A serious AE (SAE) is defined as a noxious and unintended response occurring at any dose that results 
in any of the following outcomes: death, life threatening experience, in-patient hospitalization or 
prolongation of existing hospitalization, a persistent or a significant disability/incapacity, or a 
congenital anomaly/birth defect. 
Important medical events which may not result in death, be life threatening, or require hospitalization 
may be considered as SAEs when, based upon appropriate medical judgment, they may jeopardize the 
subject and may require medical or surgical intervention to prevent one of the outcomes listed in this 
definition. 
For the purposes of this clinical trial, development of an inhibitor (as determined by the central 
laboratory) while on study drug treatment will be considered an SAE. 
NOTE: Death is an outcome and not an event. The condition leading to death is the event. Death will 
be considered an event only when no other information regarding the cause of death is available. 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        55 
 
Hospitalization that is planned before inclusion into the study or outpatient treatment without 
overnight hospitalization is not considered a SAE. Hospitalization that occurs during a trial for social 
reasons (e.g., transportation difficulties, respite care) is not considered to be a SAE. 
9.1.3. 
Definition of an Adverse Drug Reaction 
An adverse drug reaction (ADR) is defined as an unwanted response to APVO101 which is noxious 
and unintended response to APVO101 and which occurs at doses normally used in humans for 
prophylaxis, diagnosis, for therapy of disease or modification of physiological function. 
Expected ADRs are defined as ADRs whose nature (i.e., specificity or outcome), severity or frequency 
is consistent with the term or description used on the most current APVO101 Investigator’s Brochure. 
Unexpected ADRs are defined as ADRs whose nature (i.e., specificity or outcome), severity or 
frequency is either not identified, or is not consistent with the term or description used in the most 
current APVO101 Investigator’s Brochure. 
9.2. 
Assessment of Severity (Intensity) and Causality 
All AEs, including those that are not of a serious nature and those that are expected, will be 
documented by the investigators (or designates) in the source documents and appropriately transcribed 
onto separate data forms provided for this purpose. 
All AEs will be examined by the investigator or designate for assessment of both severity and causality 
using the criteria outlined in Section 9.2.1 and Section 9.2.2, respectively. 
9.2.1. 
Assessment of Severity (Intensity) 
Severity relates to the intensity of an AE. Adjectives used to describe the severity of an AE include 
mild, moderate, or severe. These are defined below. 
Mild: awareness of a sign or symptom but subject can tolerate. 
Moderate: discomfort enough to cause interference with normal daily activity. 
Severe: resulting in an inability to do work or do usual daily activity. 
An AE that is assessed as severe should not be confused with an SAE. Severity is not synonymous 
with “serious”, which is based on patient/outcome, or action criteria usually associated with the events 
that pose a threat to a patient’s life or functioning. An event is described as ‘serious’ when it meets 
one of the pre-defined outcomes as described in Section 9.1.2. 
It is important to note that both AEs and SAEs can be assessed as severe. 
9.2.2. 
Assessment of Causality (ICH Classification) 
The causal relationship between an AE and APVO101 is defined as an established relationship 
between the occurrence of an AE and exposure to APVO101. Causality is assessed using the algorithm 
shown in Table 4: Causality Assessments of Reported Adverse Events. 
 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        56 
 
Table 4: Causality Assessments of Reported Adverse Events 
 
Unrelated 
No temporal association to study product. An alternate etiology has been established. 
The event does not follow the known pattern of response to study product. The event does not 
reappear or worsen with re-challenge. 
Possibly related 
Reasonable temporal relationship to study product. The event is not readily produced by 
clinical state, environmental, or other interventions. 
The event follows a known pattern of response to the study product or as yet unknown pattern 
of response 
The event is not readily produced by clinical state, environmental, or other interventions. 
The event follows a known pattern of response to the study product or as yet unknown pattern 
of response 
Probably related 
There is a reasonable temporal association with the study product. 
The event is not readily produced by clinical state, environmental, or other interventions. 
The event follows a known pattern of response to the study product. The event decreases with 
de-challenge 
Definitely related 
There is a reasonable temporal relationship to the study product. 
The event is not readily produced by clinical state, environmental, or other interventions. 
The event follows a known pattern of response to the study product. The event decreases with 
de-challenge and recurs with re-challenge. 
 
In accordance with ICH E2A and 21.CFR.312, the following definitions are used to assess causality 
(relatedness) of the adverse events: 
Related: There is a reasonable possibility that the AE was caused by the product in question. The 
expression “reasonable possibility” is meant to convey in general that there are facts (evidence) or 
arguments to suggest a causal relationship. 
Not-related / No relationship: The AE is clearly or most probably caused by other etiology such as 
the patient’s underlying condition, therapeutic intervention or concomitant therapy, or the delay 
between the administration of the product and the onset of the AE is incompatible with a causal 
relation, or the AE started before the administration of the product. 
Adverse events reported as definitely related, probably related, possibly related, will be considered as 
related AEs. 
9.3. 
Description of Current Safety Profile for APVO101 
Based on safety information collected from clinical trials involving APVO101, the safety profile is 
comparable to other recombinant factor IX products. 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        57 
 
In study IB1001-01, all reported AEs assessed as definitely, probably and possibly related to 
APVO101 were considered to be related to APVO101 exposure and thus are defined as ADRs. 
None of the reported ADRs were considered serious or severe. 
Of the ADRs reported, only headache was reported more than once following administration of 
APVO101 to study subjects participating in IB1001-01; five events in 2.6% of study subjects. 
Headache has also been reported with other recombinant factor IX products. 
Other ADRs (reported only once) included asthenia, injection site discomfort, influenza, anti- factor 
IX antibody positive (non-inhibitory), dysgeusia, lethargy, apathy, depression and pruritic rash. 
Refer to the current APVO101 Investigator’s Brochure for more details on regarding the safety profile 
for APVO101. 
9.4. 
Adverse Event Reporting 
The occurrence of AEs will be monitored throughout the clinical trial and will cover all participating 
subjects. Trial subjects and/or their parent or legal guardian will be provided with a 24-hour telephone 
number to contact trial personnel in case of an untoward reaction. 
In the event of a reported occurrence of hypersensitivity and allergic reactions, anaphylaxis, and/or 
anaphylactic shock reactions, including but not limited to, symptoms of difficulty breathing, shortness 
of breath, swelling, hives, generalized urticaria, tightness of the chest, bronchospasm, laryngospasm, 
wheezing, hypotension, blurred vision, record these events on the APVO101 Serious Adverse Event 
Form and transmit the form within 24 hours to Medexus Pharmacovigilance using the following 
contact information: 
Email: safetydesk@psi-cro.com 
The investigator must follow all AEs to resolution, or up to 30 days after the subject has completed 
the trial, whichever occurs first. The investigator must follow serious related AEs to resolution, or in 
the case of disability or incapacity, until the condition has stabilized. In the event that a patient does 
not complete the trial, efforts must be made to obtain information regarding all AEs, with a minimum 
follow-up of 30 days post-dosing. 
9.5. 
Reporting of SAEs 
The investigator will report all SAEs to the sponsor by telephone or e-mail within 24 hours of the 
investigator’s knowledge of SAE occurrence. This will be followed by a fax or e-mail copy of the 
SAE Form. A written SAE report by the investigator to the sponsor (including medical summary of 
the SAE) must follow within three days of the investigator’s knowledge of SAE occurrence. 
All SAE reports should be made to Pharmacovigilance Department and the clinical trial medical 
monitor using the contact information indicated below: 
 
 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        58 
 
Clinical Safety Surveillance 
AND 
Clinical Trial Medical Monitor 
Rebecca Bremer, RN, BSN 
Maria Fico, MD 
Stephanie Collins, PharmD 
PSI CRO AG 
ProPharma Group 
Phone: +39 327 344 7053 
Email: safetydesk@psi-cro.com 
Email: maria.fico@psi-cro.com 
 
9.6. 
Safety Data Monitoring 
A Safety Monitoring Committee (SMC) will provide ongoing review of safety data during the trial. 
The SMC will be comprised of the sponsor Medical Monitor, the sponsor Safety Surveillance Officer, 
and one or more study investigators.  
Following study initiation, the SMC will meet as needed to review ongoing safety data. The SMC will 
be responsible for assessing safety and monitoring overall conduct and integrity of the trial. In 
fulfilling these responsibilities, the SMC may make recommendations concerning continuation and/or 
stopping of the trial as it relates to safety and risk to the subject population. 
If any one study subject develops an inhibitor (as determined by the central laboratory), regardless of 
the titer, the SMC will be informed. If a second study subject develops an inhibitor, the study will be 
placed on hold and the SMC, IRB/EC, FDA, and local regulatory authorities will be informed. 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        59 
 
10. 
OTHER ASSESSMENTS 
10.1. 
Assessment of Major and Target Joint(s) 
Assessment of major joints (hips, knees, ankles, elbows, shoulders, wrists, etc.) will be performed by 
a physical therapist or the investigator (at Screening, 50 ED and 100 ED visits) and will include 
evaluation of joint swelling, muscle atrophy, range of motion, and presence/absence of flexion 
contracture. 
A target joint is defined as a joint with three or more bleeds within a 3-month period. 
The number of target joints will be documented before (at Screening) and after APVO101 prophylaxis 
treatment (at 50 ED and 100 ED visits; see Table 1). 
Assessment of target joint(s) will be performed by a physical therapist or the investigator (at 
Screening, 50 ED and 100 ED visits) and will include evaluation of joint swelling, muscle atrophy, 
range of motion, and presence/absence of flexion contracture. 
10.2. 
Subject-reported Assessments 
Subject diaries will be maintained by all subjects and/or their parent or legal guardian and evaluated 
by site investigators during follow-up visits. 
Subjects and/or their parent or legal guardian will record details of each bleeding episode, including 
the reason for bleeding, symptoms and signs associated with the bleed, dose amount required to 
control bleeding, administration of each dose, and outcome of the treatment of the bleed. 
Subjects and/or their parent or legal guardian will record time, date, and amount of each dose 
administered. 
10.3. 
Mutation Genotyping 
Blood sampling for DNA extraction to determine molecular diagnosis of factor IX gene mutation will 
be completed at the 12 ED Visit. Note, for patients below 10 kg this may be done at any time during 
the study when blood volumes allow. 
If a subject has previously been genotyped and a report documenting the type of mutation is available, 
this test will not be performed. A copy of the report will be collected as part of clinical monitoring. 
 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        60 
 
11. 
STATISTICAL ISSUES IN TRIAL DESIGN 
11.1. 
Sample Size Calculation 
No formal sample size calculation was performed given that all planned analyses are descriptive in 
nature. Up to 22 subjects will be enrolled to ensure that at least 15 to 20 evaluable subjects complete 
all phases of the study. The target sample size is intended to enhance the existing pediatric sample size 
to be compliant with the EMA regulatory guidelines and the FDA post-marketing requirement for 
APVO101 (see Section 3.3). 
11.2. 
Clinical Trial Endpoints 
11.2.1. 
PK Endpoints 
All PK endpoints will be calculated based on the factor IX concentration levels. The actual time of 
sampling and actual dose will be used for the dose/time dependent PK endpoints. The PK endpoints 
listed below will be calculated with and without baseline correction. 
Baseline correction will be performed using the subtraction method such that all post-infusion 
concentrations will have the pre-infusion concentration subtracted. All negative baseline-corrected 
concentrations will be set to zero prior to the calculation of PK parameters. 
The following PK endpoints will be calculated: 
• Maximum post-infusion plasma concentration (Cmax) 
• Incremental recovery 
• In vivo recovery (IVR) 
• Area under the plasma concentration curve from time 0 to infinity (AUC0-∞) 
• Area under the plasma concentration curve from time 0 to t (AUC0-t) 
• Mean residence time (MRT) 
• Elimination rate constant (λZ) 
• Terminal half-life (t1/2) 
• Clearance (CL) 
• Volume of distribution at steady-state (Vdss) 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        61 
 
11.2.2. 
Efficacy Endpoints 
The following efficacy endpoints will be evaluated for the Treatment and Continuation phases of the 
study: 
Primary Efficacy Endpoint: 
• Annualized bleeding rate (ABR) while on prophylaxis to prevent bleeding episodes. 
Secondary Efficacy Endpoints: 
The following secondary efficacy endpoints are evaluated at the bleeding episode level: 
• Subject rating of efficacy 
• Change in pain 
• Change in swelling 
• Time from onset of bleeding to the first infusion 
• Time from onset of treatment until resolution of the bleeding episode 
• Number of infusions required to treat the bleeding episode 
The following secondary efficacy endpoints are evaluated at the subject level: 
• Investigator rating of APVO101 prophylaxis efficacy 
• Investigator rating of APVO101 efficacy for control and management of bleeding episodes 
Exploratory Efficacy Endpoints: 
The following endpoints will be calculated for surgical procedures (if applicable): 
• Surgeon assessment of estimated blood loss at time of surgery 
• Surgeon assessment of post-surgery blood loss (at 12-hour and 24-hour post-surgery time 
points) 
11.2.3. 
Safety Endpoints 
The following safety endpoints will be evaluated: 
• Adverse events 
• Inhibitory factor IX antibodies 
• Non-inhibitory factor IX antibodies 
• Anti-CHOP antibodies 
• Thrombogenicity markers 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        62 
 
11.3. 
Interim Analyses 
When a sufficient number of subjects completes their 50 ED visit, available PK and safety/efficacy 
data (for at least 50 ED) will be included for data analysis of an integrated pediatric report required 
for US post-marketing requirement. 
11.4. 
Planned Method of Analyses 
A formal statistical analysis plan (SAP) will be prepared prior to the execution of any statistical 
analyses and will provide additional details on the planned methods for analysis. 
11.4.1. 
PK Analysis 
No formal statistical comparisons of PK endpoints are planned, however all PK parameters calculated 
with and without baseline correction, both for initial and repeat PK assessments will be summarized 
through the use of descriptive statistics, including the mean, median, geometric mean, standard 
deviation, range and 95% confidence interval for the mean. 
Listings will be prepared for individual concentrations over time as well as the PK parameters by 
subject. 
11.4.2. 
Efficacy Analysis 
No formal statistical comparisons are planned. Descriptive summaries and listings of all treatment and 
continuation phase efficacy endpoints, as well as the surgeon’s assessment of estimated blood loss 
during and after surgery, will be provided. 
The annualized bleeding rate will be calculated and summarized, including the median, interquartile 
range and the 95% exact confidence interval for the median, assuming that the rates follow a Poisson 
distribution. 
11.4.3. 
Safety Analysis 
All AEs and SAEs will be coded using MedDRA. The analyses of AEs will include descriptive 
statistics and will be summarized through the use of frequency tables overall and by type (AE or SAE), 
body system and preferred term, intensity and relationship of events to treatment. 
Summary statistics for laboratory tests (including non-inhibitory and inhibitory factor IX antibody 
levels and anti-CHOP results) over time will be provided. 
Levels of thrombogenic markers will be summarized by subject and evaluated against criteria for this 
measurement. 
The incidence of non-inhibitory factor IX antibodies and incidence of anti-CHOP antibodies will be 
calculated along with corresponding 95% exact confidence intervals using the binomial distribution. 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        63 
 
12. 
REGULATORY AND ETHICAL ISSUES 
12.1. 
Declaration of Helsinki 
The investigator shall ensure that this trial is conducted in accordance with the “Declaration of 
Helsinki” (Version 6, October 2008). 
12.2. 
Informed Consent / Assent 
The investigator (or his/her representative) will obtain written informed consent, or assent where 
applicable, from prospective trial candidates/legal guardians before enrolment or the performance of 
any trial procedures. The proper completion of consent/assent forms will be monitored by sponsor 
personnel and the original signed informed consent form(s) (ICF) and assent form will be maintained 
in the Investigator site file.  
A copy of the signed ICF or assent form must be given to the subject and/or their parent or legal 
guardian. If the ICF or assent form is revised, all trial subjects and/or their parent or legal guardian 
who are ongoing in the trial must be re-consented to the current IRB/EC-approved version of the 
ICF/assent form at their next trial visit.  
12.3. 
Institutional Review Board (IRB) / Ethics Committee (EC) 
Before the start of the trial, the Investigator’s Brochure, the protocol, proposed ICF/assent form, 
subject compensation (if any), Medexus-approved trial materials and advertisements, and any other 
written information to be provided to the subject and/or their parent or legal guardian, will be 
submitted to a properly constituted IRB/ EC for review. Medexus must receive a copy of the written 
approval from the IRB/EC for all of the above applicable documents prior to recruitment of subjects 
into the trial and shipment of APVO101. 
The IRB/EC must provide written approval for all amendments to any of the above documents prior 
to implementation of these amendments at the investigational site. The investigator is obliged to report 
SAEs, as well as any unanticipated problems, to the IRB/EC in addition to other information as 
required by the IRB/EC. 
The names (or title, if IRB/EC procedures prohibit publishing of names) and associated backgrounds 
of the members of IRB/EC (to assist in assuring that the board membership is properly constituted and 
operates according to required regulations) will be given to the sponsor (Medexus ) prior to the start 
of the trial along with a signed and dated statement stating that the protocol and Informed Consent 
Form and, where applicable, any other document listed above, have been approved by them. 
All correspondence between the investigator and the IRB/EC will be available for review by the 
sponsor (or designate), Contract Research Organization (CRO) personnel, and the applicable 
regulatory authorities. 
12.4. 
Documentation Required Prior to Trial Initiation 
The investigator (or designate) is responsible for forwarding the following documents to Medexus for 
review prior to trial initiation: 


 
  Protocol APVO101-903, Version 3.0 Amendment 2 
 
 
Confidential  
 
        64 
 
• Signed protocol signature page, form FDA 1572 (or equivalent, depending on local 
regulatory requirements), financial disclosure form, debarment certification statement, 
Clinical Trial Agreement, and any other required regulatory documents. 
• Copy of IRB/EC-approved ICF/assent form. 
• Copy of the written IRB/EC approval for the protocol, Investigator’s Brochure, informed 
consent form(s), subject compensation (if any), any trial materials and advertising, and any 
other written information to be provided to the subject and/or their parent or legal guardian. 
• Current Curriculum Vitae and a photocopy of medical license (if applicable) of the 
principal investigator, co/sub investigators and other site personnel as required by the 
Sponsor/CRO. 
• Written statement that the IRB/EC is properly constituted and operates according to 
required regulations. Investigators participating in this study, if IRB/EC members, should 
state in writing that they have abstained from voting in regard to this protocol. 
• Laboratory normal ranges and documentation of laboratory certification. 
• Signed site contract agreement. 
12.5. 
Subject Confidentiality 
The investigator must ensure the anonymity of each subject is maintained at all times. Subjects should 
only be identified by their initials and Subject Trial ID (enrolment) number on the CRF, or on any 
other trial documents provided to the Sponsor or their designate(s). Any documents that identify the 
subject should be kept in strict confidence by the principal investigator. 
Based on ICH GCP guidelines and regulatory requirements, the investigator is required to allow 
authorized personnel of Medexus  (or its designate), the IRB/EC, and members of the appropriate 
regulatory authorities to review subject’s files that are related to APVO101-903. Subjects and/or their 
parent or legal guardian must be informed that his/her records may be reviewed by Medexus, its 
designate(s), the IRB/EC and the appropriate regulatory authorities through direct access to the 
subject’s original medical records. 
 


Protocol APVO101-903, Version 3.0, Amendment 2 
Confidential  
 
        65 
 
13. 
ADMINISTRATIVE AND LEGAL REQUIREMENTS 
13.1. 
Sponsorship 
This clinical trial is sponsored by Medexus Pharma Inc., d.b.a Aptevo BioTherapeutics, LLC 
located at 29 N Wacker Drive, Suite 704, Chicago, IL 60606, USA. 
The APVO101 drug substance is manufactured for Medexus by AGC Biologics, Inc., 21511 23rd 
Dr SE, Bothell, WA 98021, USA.  
The APVO101 drug product is formulated for Medexus by Patheon Italia S.p.A., 2° Trav. SX Via 
Morolense 5, 03013 Ferentino FR – Italia. 
The final APVO101 drug product packaging and labeling for this clinical trial is performed for 
Medexus by Almac Clinical Services 9 Charlestown Road, Seagoe Industrial Estate, Craigavon, 
BT63 5PW, UK 
13.2. 
Protocol Amendments 
Protocol amendments will only be made by Medexus. Any change to the protocol must be made 
in the form of a formal amendment to the protocol and must be approved in writing by the principal 
investigator, the sponsor, and the IRB/EC and regulatory agencies (where applicable) prior to 
implementation. The investigator must receive written IRB/EC approval for all protocol 
amendments prior to implementing protocol amendments at the trial site, and the investigator must 
send a copy of any IRB/EC correspondence and all approval/disapproval letters from the IRB/EC 
to Medexus. 
13.3. 
Deviations from the Protocol 
The investigator agrees to conduct the clinical trial in compliance with the protocol agreed to by 
Medexus and approved by the IRB/EC. The investigator and Medexus shall sign the protocol to 
confirm this agreement. 
The investigator will not deviate from this protocol for any reason without prior approval of the 
sponsor and the IRB/EC, except in cases of medical emergencies. The investigator may deviate 
from the protocol without the prior approval of the IRB/EC or Medexus only when the deviation 
is necessary to eliminate an apparent immediate hazard to the subjects. In that event, the 
investigator must notify the IRB/EC and Medexus in writing as soon as possible and no more than 
five working days after the deviation is implemented. The investigator shall document and explain 
any deviation from the approved protocol. 
13.4. 
Source Documentation and Storage 
The principal investigator will maintain the following information: 
• Medical history/physical condition of the trial subject before involvement in the trial 
sufficient to verify protocol entry criteria. 


Protocol APVO101-903, Version 3.0, Amendment 2 
Confidential  
 
        66 
 
• Dated and signed notes on the day of entry into the trial including the trial number, the 
drug being evaluated, subject trial ID number assigned, and a statement that informed 
consent/assent form was obtained, noting the time the consent was obtained. 
• Dated and signed notes from each trial subject visit that refer to the protocol or CRFs 
for further information, if appropriate (i.e., for specific procedures and exams). 
• Subject diary page(s) following the assessment visit. 
• The investigator will assess each abnormal lab result as clinically significant or not 
clinically significant. For clinically significant results, a brief explanation will be 
written on the laboratory report. These assessments will be noted on the laboratory 
report source document and signed and dated on the date of the investigator’s review. 
• Notes regarding concomitant medications taken during the trial (including start and 
stop dates). 
• Source documents regarding adverse events occurring during the trial including date of 
onset and cessation, seriousness, severity, causality, action taken and related 
concomitant medications. 
• Trial subjects’ condition upon completion, or withdrawal from, the trial. 
• All communications with the IRB/EC responsible for the trial. 
• Drug accountability records. 
• Any other records as required by the Sponsor/designate, the IRB/EC or the regulatory 
authorities. 
The investigator must arrange for the retention of the subject identification codes according to local 
regulatory requirements. Subject files and other source data must be securely stored and kept for 
the maximum time permitted by the hospital, institution or private practice but not less than local 
regulatory requirements. Archival data may be held on microfiche or electronic record, provided 
that a backup exists, and that hard copy can be obtained from it if required. If source documents 
are to be destroyed as per hospital or local regulatory policy, the investigator is requested to contact 
the sponsor. 
Records from the trial that identify the subject will be confidential except that they may be given 
to and inspected by the sponsor of the trial or designate(s), the IRB/EC, the Food and Drug 
Administration, other government agencies as appropriate, and will not otherwise be released 
except as required by law. All information provided to the investigator by the sponsor is to be 
considered confidential unless otherwise stated. 
13.5. 
Data Forms 
Detailed specifications for data management will be outlined in a Data Management Plan (DMP) 
that will be finalized before data collection is initiated. The DMP is a dynamic document that will 
be updated throughout the conduct of the study, as needed, to ensure the accuracy and quality of 
the database. 


Protocol APVO101-903, Version 3.0, Amendment 2 
Confidential  
 
        67 
 
Designated study site personnel will record study data into electronic CRFs within the study 
electronic data capture (EDC) system. The investigator is responsible for the accuracy of the data 
entered into the CRFs and will be required to electronically sign the forms to indicate agreement 
with the recorded data. 
Security processes will be in place to ensure the safety of all systems and data. Every effort will be 
made to ensure that data are kept secure so that they can only be accessed by authorized staff. 
13.6. 
Monitoring 
At the time the trial is initiated, monitors from the sponsor/CRO will thoroughly review the 
protocol and data forms with the investigators and their staff. During the trial, the monitors will be 
available to discuss by telephone, e-mail, or in person (during site visits), questions regarding study 
criteria, adverse reactions, removal of subjects from the trial, conduct of the trial and other clinical 
trial matters. Monitors from the sponsor/CRO will visit at the initiation of the trial, during the trial 
and at the completion of the trial. At the time of each monitoring visit, the monitors will check the 
case report forms of the subjects to ensure that all items have been completed, that the data are 
accurate and obtained in the manner specified in the protocol and that data recorded on the data 
forms for the trial agree with medical records at the site. The monitors will also check for general 
protocol and regulatory compliance by subjects and site personnel. 
13.7. 
Quality Control and Quality Assurance 
Medexus Quality Assurance department (or authorized representatives) may conduct onsite audits 
of all aspects of the clinical trial prior to, during the trial, or after the trial has been completed. The 
clinical trial may also be inspected by regulatory authorities or the IRB/EC to verify that the trial 
is being or has been conducted in accordance with protocol requirements, GCP, as well as the 
applicable regulatory requirements. 
13.8. 
Publication Policy 
Data arising from this trial are the sole property of the sponsor of the trial, Medexus. The sponsor 
must provide written, prior agreement to any publication based, in whole or in part, on data from 
this trial. All proposed abstracts, manuscripts or presentations from the study must be provided to 
Medexus for review at least 60 days prior to submission for publication/presentation. Any 
information identified by Medexus as confidential must be deleted prior to submission. 
The Publication Policy applicable to this protocol is the one agreed upon and described in the 
Clinical Trial Agreement between Medexus and the principal investigator. 


Protocol APVO101-903, Version 3.0, Amendment 2 
Confidential  
 
        68 
 
14. 
REFERENCES 
1. Ingerslev J. Pharmacovigilance studies in haemophilia. Haemophilia. 2007;13:121-123. 
2. Shord SS, Lindley CM. Coagulation products and their uses. Am J Health Syst Pharm, 
2000;57(15):1403–1417. 
3. Srivastava A, et al. World Federation of Hemophilia, Guidelines for the Management of 
Hemophilia, Haemophilia 2013;19:e1–e47. 
4. Giangrande P. Hemophilia B: Christmas disease. Expert Opin in Pharmacother. 
2005;6(9):1517-1524. 
5. BENEFIX [Coagulation Factor IX (Recombinant)] US Prescribing Information. Pfizer. 
2012. 
6. RIXUBIS [Coagulation Factor IX (Recombinant)] US Prescribing Information. Baxter 
Healthcare Corporation. 2014. 
7. ALPROLIX [Coagulation Factor IX (Recombinant), Fc Fusion Protein]. US Prescribing 
Information. Biogen Idec, Inc. 2014. 
8. IDELVION® [Coagulation Factor IX (Recombinant), Albumin Fusion Protein]. US 
Prescribing Information. CSL Behring LLC. 2018. 
9. REBINYN® [Coagulation Factor IX (Recombinant), GlycoPEGylated]. US Prescribing 
Information. Novo Nordisk Inc. 2017. 
10. Di Scipio RG, Hermodson MA, Yates SG, Davie EW. A comparison of human prothrombin, 
factor IX (Christmas factor), factor X (Stuart factor), and protein S. Biochemistry. 
1977;16(4):698-706. 

SAP_001.pdf: 
Medexus Pharma, Inc. 
 
 
 
 
STATISTICAL ANALYSIS PLAN 
 
 
 
PROTOCOL APVO101-903 
Evaluation of a Recombinant Factor IX Product, APVO101, in Previously Treated 
Pediatric Patients with Hemophilia B 
 
 
Protocol Code: 
APVO101-903 
SAP Version: 
Final, version 2.1 
SAP Date: 
28-MAR-2023 
Author: 
Anna Ignatenko, Group Leader Biostatistics, PSI 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
CONFIDENTAL 
Page 1 of 26 


Statistical Analysis Plan: APVO101-903 
Review Status: Final 
Version: Version 2.1 
Version Date: 23-MAR-2023 
CONFIDENTAL 
Page 5 of 26 
 
 
 
TABLE OF CONTENTS 
DOCUMENT HISTORY ................................................................................................................................. 2 
APROVAL SIGNATURES ............................................................................................................................ 4 
TABLE OF CONTENTS ................................................................................................................................ 5 
1. 
LIST OF ABBREVIATIONS ................................................................................................................ 7 
2. 
DEFINITIONS ...................................................................................................................................... 7 
3. 
INTRODUCTION ................................................................................................................................. 9 
4. 
STUDY OBJECTIVES ......................................................................................................................... 9 
4.1 
PRIMARY OBJECTIVES ......................................................................................................................... 9 
4.2 
EXPLORATORY OBJECTIVES ................................................................................................................. 9 
5. 
STUDY DESCRIPTION ....................................................................................................................... 9 
5.1 
STUDY DESIGN AND TREATMENT ......................................................................................................... 9 
5.1.1 
PK Phase ..................................................................................................................................10 
5.1.2 
Treatment Phase .......................................................................................................................10 
5.1.3 
Continuation Phase ...................................................................................................................10 
5.1.4 
Surgery .....................................................................................................................................11 
5.2 
SAFETY MONITORING COMMITTEE ......................................................................................................11 
6. 
RANDOMIZATION AND BLINDING ..................................................................................................11 
7. 
SAMPLE SIZE AND POWER CALCULATION ..................................................................................11 
8. 
ANALYSIS ENDPOINTS ....................................................................................................................12 
8.1 
PK ENDPOINTS ..................................................................................................................................12 
8.2 
EFFICACY ENDPOINTS ........................................................................................................................12 
8.2.1 
Primary Efficacy Endpoint: ........................................................................................................12 
8.2.2 
Secondary Efficacy Endpoints ..................................................................................................12 
8.2.3 
Exploratory Efficacy Endpoints .................................................................................................12 
8.3 
SAFETY ENDPOINTS ...........................................................................................................................12 
9. 
ANALYSIS POPULATIONS ...............................................................................................................12 
10. 
ANALYTICAL PLAN AND STATISTICAL METHODS ......................................................................13 
10.1 
GENERAL CONVENTIONS AND STATISTICAL CONSIDERATIONS ...........................................................13 
10.2 
DEFINITION OF BASELINE, STUDY VISITS, AND VISIT WINDOWS ..........................................................13 
10.3 
HANDLING OF MISSING DATA ...........................................................................................................13 
10.3.1 Dates Imputations .....................................................................................................................13 
10.4 
PATIENT DISPOSITION .....................................................................................................................14 
10.5 
PROTOCOL DEVIATIONS ..................................................................................................................14 
10.6 
PATIENT CHARACTERISTICS ............................................................................................................14 
10.6.1 Baseline and Demographic Characteristics ..............................................................................14 
10.6.2 Medical History and Current Medical Conditions ......................................................................15 
10.6.3 Prior and Concomitant Medications ..........................................................................................16 
10.6.4 Concomitant Procedures ...........................................................................................................16 
10.7 
EFFICACY ENDPOINTS AND ANALYSIS ..............................................................................................16 
10.7.1 Analysis of Primary Efficacy Endpoint .......................................................................................16 
10.7.2 Analysis of Secondary Efficacy Endpoints ................................................................................17 
10.7.3 Analysis of Exploratory Efficacy Endpoints ...............................................................................18 
10.8 
SAFETY ENDPOINTS AND ANALYSIS .................................................................................................18 


Statistical Analysis Plan: APVO101-903 
Review Status: Final 
Version: Version 2.1 
Version Date: 28-MAR-2023 
CONFIDENTAL 
Page 6 of 26 
 
 
10.8.1 Exposure to Study Treatment and Compliance.........................................................................18 
10.8.2 Adverse Events .........................................................................................................................19 
10.8.3 Laboratory Data ........................................................................................................................20 
10.8.4 Vital Signs and Other Safety Parameters ..................................................................................20 
10.9 
OTHER ENDPOINTS AND ANALYSIS ..................................................................................................21 
10.9.1 Genotypes .................................................................................................................................21 
11. 
INTERIM ANALYSIS ..........................................................................................................................21 
12. 
DEVIATIONS FROM ANALYSIS AS DESCRIBED IN THE PROTOCOL .........................................21 
13. 
PROGRAMMING SPECIFICATIONS .................................................................................................22 
14. 
LIST OF TABLES AND LISTINGS ....................................................................................................22 
15. 
APPENDIX I. SCHEDULE OF ASSESSMENTS ................................................................................23 


Statistical Analysis Plan: APVO101-903 
Review Status: Final 
Version: Version 2.1 
Version Date: 23-MAR-2023 
CONFIDENTAL 
Page 7 of 26 
 
 
1. 
LIST OF ABBREVIATIONS 
ABR 
Annualized bleed rate 
AE 
Adverse event 
ALP 
Alkaline Phosphatase 
ALT 
Alanine Aminotransferase 
AST 
Aspartate Aminotransferase 
ATC 
Anatomical Therapeutic Chemical 
bp 
Base pairs 
bpm 
Beats per minute 
BUN 
Blood Urea Nitrogen 
CBC 
Complete Blood Counts 
CHOP 
Chinese hamster ovary cell proteins 
eCRF 
Electronic case report form 
ED 
Exposure day 
F1+2 
Fragment 1+2 
IV 
Intravenous 
MedDRA 
Medical Dictionary for Regulatory Activities 
PK 
Pharmacokinetics 
PT 
Preferred Term 
SAE 
Serious adverse event 
SAP 
Statistical analysis plan 
SOC 
System Organ Class 
SMC 
Safety Monitoring Committee 
SD 
Standard Deviations 
TAT 
Thrombin-antithrombin complex 
TEAE 
Treatment Emergent Adverse Event 
Q1/Q3 
Quartile 1/Quartile 3 
 
 
2. 
DEFINITIONS 
Annualized Bleeding Rate (ABR) is defined as number of bleeding episodes per year. 
 
An adverse event (AE) is defined as any untoward, undesirable, or unintended medical 
occurrence in a clinical trial subject administered APVO101 which does not necessarily have a 
causal relationship with APVO101. For purposes of this clinical trial, an AE can therefore be any 
unfavorable and unintended sign (e.g., including an abnormal laboratory finding), symptom, or 
disease temporally associated with the use of APVO101, whether or not related to the product. 
 
Examples of major surgical procedures (surgery) include synovectomy, knee or hip 
replacement, total tooth extraction, tonsillectomy and/or adenoidectomy, surgery for intracranial 
hemorrhage, radial head excision, arthrodesis, ankle surgery, abdominal surgery, 
herniorrhaphy, or surgery for major muscle bleed management. 
 
A bleeding episode will be defined as a unique entry in the subject bleeding diary. In the event 
that a bleeding episode occurring at multiple locations is recorded as multiple entries in the 
bleeding diary, these will be considered as one bleeding episode provided that all entries have 
the same start date. 
 
Bleeding episodes severity: 


Statistical Analysis Plan: APVO101-903 
Review Status: Final 
Version: Version 2.1 
Version Date: 23-MAR-2023 
CONFIDENTAL 
Page 8 of 26 
 
 
 
• 
Minor: e.g., uncomplicated hemarthroses and superficial muscle (except iliopsoas) 
with no neurovascular compromise, other soft tissue bleeds 
• 
Moderate: e.g., hemarthrosis of longer duration, recurrent hemarthrosis, mucous 
membranes, deep lacerations, hematuria 
• 
Major or life-threatening: e.g., iliopsoas, deep muscle with neurovascular injury, 
substantial blood loss, central nervous system, pharyngeal, retropharyngeal, 
retroperitoneal. 
 
Compliance will be calculated for each subject based on actual and planned number of 
APVO101 doses in the study. The actual number of doses will be counted from the first dose in 
the treatment phase up to and including the last APVO101 dose date on study. The number of 
infusions expected will be calculated for each subject based on their prescribed dosing regimen. 
If a patient received APVO101 dose twice weekly during whole study compliance will be 
calculated as following: 
Compliance % = 100% *[number of infusions recorded in the subject diary/ (date of last 
dose for prophylaxis – date of first dose)*2/7] 
 
if a patient first received APVO dose twice weekly and then dose frequency was 
adjusted to once weekly per investigator discretion, compliance will be calculated as 
following: 
 
Compliance % = 100% [number of infusions recorded in the subject diary/(A + B)], where 
A = [2* (date of last dose when patient was on ‘twice weekly’ frequency – date of first 
dose)]/7 
B = (date of last dose when patient was on ‘once weekly’ frequency – date of first dose 
when patient was on ‘once weekly’ frequency)]/7 
 
If patient dose-frequency was changed more than once, compliance will be calculated 
similar to the above but taking into account all periods of different dose frequencies in 
the denominator. 
 
The following measures of exposure will be presented for the study: 
Parameter 
Description 
Exposure Day (ED) 
APVO101 exposure/infusion. ED will be calculated as the total 
number of APVO101 infusions during all phases of the study: 
Pharmacokinetic (PK) [1], Treatment, and Continuation phases, 
including surgery if applicable. If a subject receives more than one 
infusion in a single day, all infusions on that day will count as one ED. 
Average Exposure per 
exposure day (IU) 
Average APVO101 dose (IU): Sum of all dosages received by a 
subject (excluding PK doses and dosing during surgery), divided by 
number of exposure days (excluding PK and surgery) 
Average Exposure per 
exposure day (IU/kg) 
Similar to above but for dose in IU/kg 
Total Exposure (IU) – 
PK phase 
Planned PK dose IU [2] 
Total Exposure (IU/kg) – 
PK phase 
Planned PK dose IU/kg [2] 
Total Exposure (IU) – 
N/A, no surgeries in the study at the moment of the Statistical Analysis 


Statistical Analysis Plan: APVO101-903 
Review Status: Final 
Version: Version 2.1 
Version Date: 23-MAR-2023 
CONFIDENTAL 
Page 9 of 26 
 
 
 
Surgeries 
Plan (SAP) update [3] 
Total Exposure (IU/kg) – 
Surgeries 
N/A, no surgeries in the study at the moment of the SAP update [3] 
Total Exposure (IU) – All 
Phases combined 
including surgeries 
Sum of all doses (IU) during the study (PK [1], Treatment and 
Continuation phases, including surgery if applicable). 
Total Exposure (IU/kg) – 
All Phases combined 
including surgeries 
Similar above but for dose in (IU/kg) 
 
[1] including additional PK during Treatment/Continuation phases 
[2] PK during Treatment/Continuation phases should not be included 
[3] if surgeries occur in the study by the time of database lock, exposure during surgeries will be derived 
similar to other total exposure parameters, i.e., as sum of all doses in IU or IU/kg associated with surgery. 
 
3. 
INTRODUCTION 
This SAP covers the statistical analysis and reporting for the protocol APVO101-903 
Amendment 2.0 dated 29 Jul 2020, and electronic case report form (eCRF) production version 
of 23 Sep 2019. 
 
4. 
STUDY OBJECTIVES 
4.1 
PRIMARY OBJECTIVES 
The following are the primary objectives of APVO101-903: 
 
• 
To evaluate safety of APVO101 in pediatric subjects with hemophilia B for at least 50 
ED; 
• 
To assess efficacy of APVO101 prophylaxis with respect to prevention of breakthrough 
bleeding and with respect to control of hemorrhaging in pediatric subjects with 
hemophilia B for at least 50 ED; 
• 
To evaluate PK of APVO101 in pediatric subjects with hemophilia B; 
• 
To evaluate APVO101 immunogenicity response (development of inhibitory and non- 
inhibitory factor IX binding antibodies and antibodies to Chinese hamster ovary cell 
proteins [CHOP]). 
4.2 
EXPLORATORY OBJECTIVES 
• 
To evaluate markers of thrombogenicity [D-dimer, thrombin-antithrombin III complex 
(TAT) and fragment 1+2 (F1+2)] during the first 24 hours post-infusion of APVO101; 
• 
To evaluate efficacy of APVO101 for perioperative management in pediatric subjects 
with hemophilia B. 
5. 
STUDY DESCRIPTION 
5.1 
STUDY DESIGN AND TREATMENT 
Study APVO101-903 is a Phase 3/4, single arm, open-label clinical trial. The purpose of the 
study is to evaluate PK, safety, and efficacy of APVO101 prophylaxis in severe or moderately 
severe hemophilia B subjects <12 years of age. The study is designed to gather information in 2 
age groups of previously treated (with a minimum of 50 previous ED to factor IX replacement 
therapy) pediatric subjects, specifically those <6 years of age and 6-12 years of age. 


Statistical Analysis Plan: APVO101-903 
Review Status: Final 
Version: Version 2.1 
Version Date: 23-MAR-2023 
CONFIDENTAL 
Page 10 of 26 
 
 
 
Study APVO101-903 consists of 3 distinct phases: 
 
• 
PK Phase 
• 
Treatment Phase (from first dose after PK phase and up to 50 ED visit) 
• 
Continuation Phase (starting from first dose after 50 ED visit) 
 
Up to 22 subjects will be enrolled in order to have 15 and 20 evaluable subjects to complete the 
study (i.e., completion of PK assessments and a minimum of 50 ED visit). Treatment with 
APVO101 to support a surgical procedure (if required) is permitted for subjects in 
Treatment/Continuation phases of the study. 
 
 
5.1.1 PK PHASE 
PK evaluation will consist of administration of a single 75±5 IU/kg dose, followed by factor IX 
activity and safety assessments up to 50 hours post-infusion. Dose will be administered after a 
4-day washout period from previous factor IX replacement therapy or 3 half-lives washout of a 
factor IX product with a prolonged half-life. 
 
5.1.2 TREATMENT PHASE 
After completion of PK Phase assessments, subjects will be treated with a prophylaxis regimen 
of APVO101. Subjects will receive a single intravenous (IV) dose of APVO101 twice weekly or 
at a frequency of infusions as determined appropriate by the investigator for the particular study 
subject for a total of 50 ED (approximately 6 months). The starting prophylaxis dose will be 
based on APVO101 recovery from PK Phase assessments (only pre-infusion and 15-30 minute 
post-infusion samples; ideally within the recommended dose range: 35 – 75 IU/kg, twice 
weekly). 
 
For treatment and control of breakthrough, spontaneous or trauma-related bleeding episodes, 
the dose should be based on severity of bleeding episodes; see below: 
 
• 
Minor bleeding episodes and/or moderate bleeding episodes: 40 – 60 IU/kg; 
• 
Major or life-threatening bleeding episodes: 60 – 100 IU/kg. 
 
During APVO101 prophylaxis treatment and/or APVO101 treatment for control and 
management of bleeding episodes, every effort will be made to ensure that the prescribed dose 
per kilogram body weight is given. However, since it may be difficult to determine fractions of a 
vial for purposes of providing an exact dose, it is acceptable to round up or down to the nearest 
vial. The process of rounding up or down should not, however, result in the study subject 
receiving >120% or <90% of the prescribed dose. The exact amount of factor IX infused must 
be recorded. 
 
5.1.3 CONTINUATION PHASE 
Following completion of the Treatment Phase (i.e., 50 ED), the investigator will assess the 
subject’s dose and either assign the most recent dose from Treatment Phase or modify the 
dose if clinically indicated for an additional ≥50 ED. The Continuation Phase dose should be 
within the recommended dose range of 35 – 75 IU/kg, twice weekly. 
 
For treatment and control of breakthrough, spontaneous or trauma-related bleeding episodes, 


Statistical Analysis Plan: APVO101-903 
Review Status: Final 
Version: Version 2.1 
Version Date: 23-MAR-2023 
CONFIDENTAL 
Page 11 of 26 
 
 
 
the dose should be based on severity of bleeding episodes; see below: 
 
• 
Minor and/or moderate bleeding episodes: 40 – 60 IU/kg 
• 
Major or life-threatening bleeding episodes: 60 – 100 IU/kg 
 
5.1.4 SURGERY 
In the event of a minor or major surgery during the course of study participation (Treatment/ 
Continuation Phases), use of either bolus or continuous infusion of APVO101 for surgical 
coverage is permissible. 
 
Examples of major surgical procedures include synovectomy, knee or hip replacement, total 
tooth extraction, tonsillectomy and/or adenoidectomy, surgery for intracranial hemorrhage, radial 
head excision, arthrodesis, ankle surgery, abdominal surgery, herniorrhaphy, or surgery for 
major muscle bleed management. 
 
The following dosing is recommended for major surgical procedures: 
 
• 
If using bolus infusions, an infusion of up to 120 IU/kg will be given within 1 hour prior to 
the start of the procedure, followed by an infusion of approximately 60 IU/kg 12 hours 
after the first infusion, and up to 120 IU/kg 24 hours after the first infusion, depending on 
the subject’s post-infusion factor IX activity. This regimen of bolus infusions will continue 
every 12 hours as long as the physician and surgeon deem necessary, but for a 
minimum of 3 days post-procedure for major surgery or a minimum of 1 day post- 
procedure for minor surgery. 
• 
If administering a continuous infusion, it will also continue for a minimum of 3 days post- 
procedure for major surgery or a minimum of 1 day post-procedure for minor surgery. 
The infusion rate, dose and timing of subsequent infusions and adjustments in dosing 
will be recorded and guided by factor IX assay results, with the doses of APVO101 
administered appropriately to ensure that the plasma factor IX level does not drop below 
60%. If continuous infusion is used, the plasma level of factor IX should range between 
70% and 110%. 
 
5.2 
SAFETY MONITORING COMMITTEE 
A Safety Monitoring Committee (SMC) will provide ongoing review of safety data during the trial. 
Following study initiation, the SMC will meet as needed to review ongoing safety data. The SMC 
will be responsible for assessing safety and monitoring overall conduct and integrity of the trial. 
In fulfilling these responsibilities, the SMC may make recommendations concerning continuation 
and/or stopping of the trial as it relates to safety and risk to the subject population. 
6. 
RANDOMIZATION AND BLINDING 
The study is an open-label single-arm study; subjects and members of the clinical study team 
will not be blinded to treatment. 
 
7. 
SAMPLE SIZE AND POWER CALCULATION 
No formal sample size calculation was performed given that all planned analyses are descriptive 
in nature. Up to 22 subjects will be enrolled to ensure that at least 15 to 20 evaluable subjects 
complete the study (i.e., completion of PK assessments and a minimum of 50 ED). The target 
sample size is intended to enhance the existing pediatric sample size to be compliant with the 
European Medicines Agency regulatory guidelines and the Food and Drug Administration post- 


Statistical Analysis Plan: APVO101-903 
Review Status: Final 
Version: Version 2.1 
Version Date: 23-MAR-2023 
CONFIDENTAL 
Page 12 of 26 
 
 
 
marketing requirement for APVO101. 
 
8. 
ANALYSIS ENDPOINTS 
8.1 
PK ENDPOINTS 
PK data will be listed. Detailed descriptions of all PK analyses are provided in a separate PK 
SAP. Analysis will be included in a separate report. 
 
8.2 
EFFICACY ENDPOINTS 
8.2.1 PRIMARY EFFICACY ENDPOINT: 
ABR while on prophylaxis to prevent bleeding episodes. 
 
8.2.2 SECONDARY EFFICACY ENDPOINTS: 
Bleeding episode level: 
 
• 
Subject rating of efficacy; 
• 
Change in pain; 
• 
Change in swelling; 
• 
Time from onset of bleeding to the first infusion; 
• 
Time from onset of treatment until resolution of the bleeding episode; 
• 
Number of infusions required to treat the bleeding episode. 
 
Subject level: 
 
• 
Investigator rating of APVO101 prophylaxis efficacy; 
• 
Investigator rating of APVO101 efficacy for control and management of bleeding 
episodes. 
 
8.2.3 EXPLORATORY EFFICACY ENDPOINTS: 
• 
Surgeon assessment of estimated blood loss at time of surgery 
• 
Surgeon assessment of post-surgery blood loss (at 12-hour and 24-hour post-surgery 
time points). 
 
8.3 
SAFETY ENDPOINTS 
• 
AEs 
• 
Inhibitory factor IX antibodies 
• 
Non-inhibitory factor IX antibodies 
• 
Anti-CHOP antibodies 
• 
Thrombogenicity markers 
 
9. 
ANALYSIS POPULATIONS 
Screened population: All screened subjects. 
 
Safety population: All subjects who received at least one dose of the study drug. This population 
will be used for all safety and efficacy analyses. 


Statistical Analysis Plan: APVO101-903 
Review Status: Final 
Version: Version 2.1 
Version Date: 23-MAR-2023 
CONFIDENTAL 
Page 13 of 26 
 
 
 
PK population: All subjects who have a valid PK assessment. A PK assessment will be 
considered valid if quantifiable and evaluable concentration is available. 
 
10. 
ANALYTICAL PLAN AND STATISTICAL METHODS 
10.1 GENERAL CONVENTIONS AND STATISTICAL CONSIDERATIONS 
All statistical analyses will be performed and data appendices will be created using the SAS 
system version 9.4 or higher. 
 
Data collected in this study will be presented in summary tables and subject data listings. 
Unless otherwise specified, all data will be summarized overall and by age group (<6 years and 
6 to <12 years). 
 
Subjects in the younger age group must remain < 6 years age throughout the treatment period 
(at least 50 ED) and the upper age group must remain < 12 years throughout the treatment 
period (at least 50 ED). 
 
Descriptive statistics (number of non-missing values, mean, standard deviation [SD], median, 
first quartile [Q1], third quartile [Q3], minimum and maximum) will be presented for continuous 
variables. The number of decimal places in mean, median and quartiles will be equal to number 
of decimal places in the data + 1, decimal places in standard deviation = decimal places in the 
data + 2, number of decimal places in minimum/maximum will be equal to number of decimal 
places in the data. 
 
Frequency distributions (counts and percentages) will be presented for categorical variables. If 
not specified otherwise, the number of observations with non-missing values will be the 
denominator for percentage calculation. Percentages will include one decimal place except for 
100% where no decimal places will be provided. 
 
By-visit and by-study phase summaries will be presented using nominal eCRF visits (which can 
be up to ±5 ED to actual exposure days, see section 15) 
 
All data collected will be presented in the data listings. Missing parts of the partial dates will be 
represented with dashes in the listings. 
 
10.2 DEFINITION OF BASELINE, STUDY VISITS, AND VISIT WINDOWS 
The last non-missing assessment made prior to the first dose of study drug will be used as the 
baseline value. The data will be analyzed according to the visits recorded in the eCRF. 
 
10.3 HANDLING OF MISSING DATA 
Rules for handling of missing attributes of adverse events are specified in section 10.8.2. Rules 
for dates imputations are defined below. 
 
10.3.1 DATES IMPUTATIONS 
The rules below will be used for classification of AEs as treatment-emergent and medications as 
concomitant or prior. Data will be presented in the data listings as collected on the eCRF. 
 
The following rules will be applied for AEs and medications with incomplete start dates: 


Statistical Analysis Plan: APVO101-903 
Review Status: Final 
Version: Version 2.1 
Version Date: 23-MAR-2023 
CONFIDENTAL 
Page 14 of 26 
 
 
 
• 
If partial start date is equal to the corresponding part of the treatment start date then 
consider the start date equal to the treatment start date, 
• 
If day is missing for start date and month and year are not the same as month and year 
for the first treatment date, then impute day 1 of the month, 
• 
If day and month are missing for start date and the year is not the same as year for the 
first treatment date, then impute January 1st of the year. 
 
The following rules will be applied for AEs and medications with incomplete end dates: 
 
• 
If day is missing for end date and month and year are non-missing, then day will be 
imputed as last day of the month, 
• 
If day and month are missing for end date and year is non-missing, then day and month 
will be imputed as December 31st. 
 
AEs and medications without any start and end date information will not be imputed. 
 
The following rules will be applied for incomplete diagnosis date/date of first treatment for 
bleeding episode: 
 
• 
If day is missing then impute day 1 of the month 
• 
If day and month are missing then impute January 1st of the year. 
 
10.4 PATIENT DISPOSITION 
Subject disposition will be summarized separately for each phase of the study. 
 
The number of subjects screened and reasons for screen failure, will be summarized in the 
screened population. 
 
The number and percentage of subjects enrolled, completing the study along with reasons for 
study discontinuation, and number of subjects in each population will be summarized in the 
Safety population. The number and percentage of subjects who complete 50 ED Visit 
(Treatment Phase), 100 ED Visit (Continuation Phase) will be summarized in each population 
and overall. 
 
A listing of study disposition data will be produced. 
 
10.5 PROTOCOL DEVIATIONS 
The number and percentage of subjects with at least one major protocol deviation and the 
categories of the major protocol deviations will be summarized in the Safety population. 
 
Protocol deviations will be classified to major and minor as specified in the Protocol Deviations 
Management Plan. 
 
All protocol deviations will be provided in a listing. 
 
10.6 PATIENT CHARACTERISTICS 
10.6.1 BASELINE AND DEMOGRAPHIC CHARACTERISTICS 
Descriptive statistics for continuous variables (age at informed consent [years], height [cm], 


Statistical Analysis Plan: APVO101-903 
Review Status: Final 
Version: Version 2.1 
Version Date: 23-MAR-2023 
CONFIDENTAL 
Page 15 of 26 
 
 
 
weight [kg], and body mass index [kg/m2]) and frequency counts and percentages for 
categorical demographic variables (gender, categorized age (<2 years, 2 - <=11 years), race, 
and ethnicity) will be summarized in the Safety population. 
 
Age at informed consent (years) will be calculated as (informed consent date–date of 
birth)/365.25. 
 
Baseline and demographics characteristics will be provided in a listing. 
 
10.6.2 MEDICAL HISTORY AND CURRENT MEDICAL CONDITIONS 
Disease characteristics will be summarized in the Safety population, and will include descriptive 
statistics for 
 
• 
age at hemophilia diagnosis (years) 
• 
time since diagnosis date (months), calculated as (informed consent date – diagnosis 
date+1)/30.4375; 
• 
time from date first treated for bleeding episode (months), calculated as (informed 
consent date–date first treated for bleeding episode date+1)/30.4375; 
• 
total number of ED of factor IX replacement therapy 
and frequency counts and percentages for: 
• 
severity; 
• 
whether factor IX mutation known (yes/no); 
• 
type of factor IX mutation; 
• 
target joints/body areas; 
• 
swelling (yes/no) and level; 
• 
muscle atrophy (yes/no) and level; 
• 
loss of range of motion (yes/no); 
• 
pronation, supination, flexion, plantar flexion and dorsiflexion levels; 
• 
flexion contracture (yes/no) and level. 
 
Bleeding history will be summarized in Safety population and will include: 
 
• 
number of bleeding episodes during 6 months prior to screening; 
• 
percentage of spontaneous bleeding episodes; 
• 
number of infusions needed to control the bleeding episode. 
 
If bleeding history is not documented, then estimations provided in the eCRF will be 
summarized. 
 
Medical history will be summarized in the Safety population and will be coded using the latest 
version of Medical Dictionary for Regulatory Activities (MedDRA) classification and summarized 
by System Organ Class (SOC), preferred term (PT) and severity grade at screening. Subjects 
having the same medical condition (based on SOC, PT, and severity grade) more than once will 
be counted only once for a particular SOC, PT, and severity grade. 
 
All medical history will be listed including medical history itself, hemophilia B history, and 
bleeding history. 


Statistical Analysis Plan: APVO101-903 
Review Status: Final 
Version: Version 2.1 
Version Date: 23-MAR-2023 
CONFIDENTAL 
Page 16 of 26 
 
 
 
10.6.3 PRIOR AND CONCOMITANT MEDICATIONS 
All prior and concomitant medications will be coded using the latest version of World Health 
Organization Drug Dictionary. 
 
The number and percentages of subjects with at least one prior non-study factor IX therapy and 
prior medications will be summarized by Anatomical Therapeutic Chemical (ATC) level 4 and 
ATC level 2 class. 
 
The number and percentages of subjects with at least one concomitant medication will be 
summarized by ATC level 4 and ATC level 2 class. 
 
Prior and concomitant medications will be summarized in the Safety population. 
 
Subjects receiving the same medication more than once will be counted only once for a 
particular medication class. A medication is considered prior if the end date of the medication is 
prior to the first study drug dose date. A medication is considered concomitant if it is 
administered after the first study drug administration. Imputation rules specified in Section 10.3 
will be applied to partial/missing dates. 
 
Medications having both start and end dates missing will be considered concomitant; in the 
case of a missing start date and not missing end date the medication will be considered 
concomitant, unless the end date is prior to the date of the first dose. 
 
All prior and concomitant medications will be provided in a listing. 
 
10.6.4 CONCOMITANT PROCEDURES 
All concomitant procedures will be coded using the latest version of MedDRA classification. A 
procedure is considered concomitant if performed after the first study drug administration. 
 
All concomitant procedures will be provided in a listing. 
 
10.7 EFFICACY ENDPOINTS AND ANALYSIS 
Efficacy data will be analyzed in the Safety population. Descriptive summaries and listings of all 
Treatment and Continuation Phase efficacy endpoints as described in section 10.7.2, as well as 
the surgeon’s assessment of estimated blood loss during and after surgery, will be provided. 
The efficacy endpoints are summarized for each study phase (Treatment and Continuation) and 
combining data across study phases. 
 
10.7.1 ANALYSIS OF PRIMARY EFFICACY ENDPOINT 
The number of bleeding episodes and the number of months observed will be determined from 
the subject diary. The months of observation will be calculated from the first date of the 
Treatment Phase to the last prophylaxis entry into the subject diary. 
 
ABR while on prophylaxis to prevent bleeding episodes will be calculated and summarized 
using median, Q1, Q3 and 95% exact confidence interval for the mean, assuming that the rates 
follow a Poisson distribution. 


Statistical Analysis Plan: APVO101-903 
Review Status: Final 
Version: Version 2.1 
Version Date: 23-MAR-2023 
CONFIDENTAL 
Page 17 of 26 
 
 
 
ABR overall = (number of bleeding episodes starting from first dose after PK Phase up to 3 days 
after the last dose of APVO101 given for prophylaxis)/[(treatment end date +3 – treatment start 
date+1)/365.25]. If a subject left the study earlier than 3 days after last dose, date of end of 
study will be taken instead of (treatment end date +3 days). 
 
ABR Treatment Phase = (number of bleeding episodes starting from first dose after PK Phase 
up to 3 days after the last dose of APVO101 given for prophylaxis up to 50 ED)/[(last dose 
≤50ED +3 – treatment start date +1)/365.25]. In case first dose after 50 ED occurred earlier than 
3 days after 50 ED then this dose date – 1 should be taken as reference end date. If a subject 
left the study earlier than 3 days after last dose in treatment phase, date of end of study will be 
taken instead of (last dose ≤50 ED + 3 days). 
 
ABR Continuation Phase = (number of bleeding episodes starting from first dose after 50 ED up 
to 3 days after last dose of APVO101 given for prophylaxis)/[(treatment end date +3 – first dose 
after 50 ED+1)/365.25]. If a subject left the study earlier than 3 days after last dose, date of end 
of study will be taken instead of (treatment end date +3 days). 
 
Note: a bleeding episode which occurred after PK dose but prior to completion of PK 
assessment will be included into ABR calculations. 
 
In addition, analysis of ABR will be repeated on the normalized data (square-root transformation 
will be used to normalize ABR). 
 
Number of subjects with at least one bleeding episode and no bleeding episodes will also be 
summarized. 
 
The analysis of ABR will be repeated for Spontaneous ABR which will consider only 
spontaneous bleeding episodes in the numerator. Denominator will remain the same as for 
ABR. Spontaneous ABR for Treatment, Continuation phases as well as overall will be derived. 
 
10.7.2 ANALYSIS OF SECONDARY EFFICACY ENDPOINTS 
Both types of secondary efficacy endpoints (bleeding episode level and subject level) will be 
presented descriptively for the Treatment Phase (bleeding episodes and subject level 
assessments occurred from first dose to 50 ED up to 3 days after last dose of APVO101 given 
for prophylaxis), Continuation Phase (bleeding episodes and subject level assessments 
occurred on or after first dose after 50 ED given for prophylaxis) and overall (all bleeding 
episodes and subject level assessments in a subject). 
 
Summaries for bleeding episode level endpoints will include: 
 
• 
Number and percentage of bleeding episodes within each category of subject’s rating of 
efficacy; 
• 
Number and percentage of bleeding episodes within each category reported by subjects 
as answer to question “How long did it take for the pain to stop?” 
• 
Number and percentage of bleeding episodes within each category of highest level of 
pain during the bleeding episode. 
• 
Number and percentage of bleeding episodes within each category reported by subjects 
as answer to question “How long did it take for the swelling to go down?” 
• 
Descriptive statistics for time from onset of bleeding to the first infusion (minutes) as 
continuous variable 


Statistical Analysis Plan: APVO101-903 
Review Status: Final 
Version: Version 2.1 
Version Date: 23-MAR-2023 
CONFIDENTAL 
Page 18 of 26 
 
 
 
• 
Descriptive statistics for time from onset of treatment until resolution of the bleeding 
episode (minutes) as continuous variable 
• 
Descriptive statistics for number of infusions required to treat the bleeding episode as 
continuous and categorical variable 
 
Note: a bleeding episode which occurred after PK dose but prior to completion of PK 
assessment will be included into ABR calculations. 
 
Summaries for subject level endpoints will include by-visit summaries for the following 
Investigator’s assessments: 
 
• 
APVO101 prophylaxis efficacy assessment 
• 
Efficacy for control of bleeding episodes assessment 
 
All data for subject assessments of bleeding episodes and Investigator assessments of efficacy 
will be listed. 
 
10.7.3 ANALYSIS OF EXPLORATORY EFFICACY ENDPOINTS: 
The following endpoints related to surgery will be summarized as frequency variables: 
 
• 
Pre- and Post-surgery assessments: 
o Surgeon’s assessment of total blood loss 
 
• 
12 hours (±3 hours) post-surgery assessment and 24 hours (±3 hours) post-surgery 
assessment: 
o Surgeon’s assessment of total blood loss 
o Surgeon’s assessment of APVO101 hemostatic efficacy 
 
All data related to surgeries will be listed including reasons for procedures, prior and post- 
surgery assessments. 
 
Vital signs collected during surgery will be listed. 
 
10.8 SAFETY ENDPOINTS AND ANALYSIS 
All safety outcomes will be analyzed in the Safety population. 
 
Safety will be evaluated by presenting summaries of exposure to study treatment, AEs, physical 
examination, vital signs, local laboratory evaluations (hematology, serum chemistry, and 
urinalysis) and central laboratory evaluations (inhibitory factor IX antibodies, non-inhibitory 
factor IX binding antibodies, anti-CHOP antibodies, and thrombogenic markers). 
 
10.8.1 EXPOSURE TO STUDY TREATMENT AND COMPLIANCE 
Exposure and compliance parameters will be summarized descriptively. Parameters to be 
summarized are specified in section 2. 
 
In addition, number and percentage of subjects who fall under the following categories (not 
mutually exclusive) of treatment exposure will be presented: 


Statistical Analysis Plan: APVO101-903 
Review Status: Final 
Version: Version 2.1 
Version Date: 23-MAR-2023 
CONFIDENTAL 
Page 19 of 26 
 
 
 
• 
Subjects with ≥ 50 ED 
• 
Subjects with ≥ 100 ED 
• 
Subjects with ≥ 150 ED 
• 
Subjects with ≥ 200 ED 
 
 
Number of surgeries overall and per subject, number of infusions due to surgeries overall and 
per surgery, and total dose administered per surgery will be calculated by treatment regimen 
(bolus vs. continuous infusion); subjects may receive both bolus and continuous infusions and, 
in such cases, will be included in the summaries for both treatment regimens. For subjects 
treated with bolus infusion, the number of bolus infusions, average APVO101 dose (IU/kg), and 
total APVO101 exposure (IU) will be presented by surgery visit (pre-surgery and post-surgery) 
and overall. For subjects treated with continuous infusion, the average APVO101 dose 
(IU/kg/hr) and total APVO101 exposure (IU) will be presented. 
 
Compliance derivation algorithm is provided in section 2. Compliance will be summarized as 
continuous variable as well as categorized into >=80%, < 80 %. Reasons for dose/frequency 
modifications will also be tabulated. 
 
Summaries described in this section will be done separately for Treatment/Continuation Phases 
combined, surgeries and overall, except for compliance and reasons for dose/frequency 
modifications which will be presented for all study duration. 
 
A by-subject listing with the treatment administration data will be presented. In addition, a listing 
of all derived parameters will be produced, and it will include total value of exposure (IU) and 
exposure days per study. 
 
Dose regimen data together with reasons for changes in dose regimen will be listed. 
 
10.8.2 ADVERSE EVENTS 
AEs will be coded using the latest version of MedDRA. The analysis of AEs will include 
descriptive statistics and will be summarized through the use of frequency tables overall and by 
type (AE or serious adverse event [SAE]) SOC and PT, intensity, and relationship of events to 
treatment. Summaries for adverse events will include number of subjects as well as number of 
events. 
 
A treatment-emergent adverse event (TEAE) is defined as an AE that occurs or worsens after 
the first study drug administration. AEs having both onset and end dates missing will be 
considered as TEAEs. AEs having missing onset date and not missing end date AE will be 
considered as TEAE unless end date is prior to the date of the first dose. 
 
Related AEs are AEs with missing, probably related, possibly related, and definitely related 
relationship to study drug. 
 
An overall summary of AEs will include the number of subjects who experienced at least one AE 
of the following categories: any TEAE; any SAE; any related TEAE, any TEAE leading to early 
study termination; and any TEAE leading to death. 
 
The incidence of TEAEs will be summarized by SOC and PT; by SOC, PT and intensity; and by 


Statistical Analysis Plan: APVO101-903 
Review Status: Final 
Version: Version 2.1 
Version Date: 23-MAR-2023 
CONFIDENTAL 
Page 20 of 26 
 
 
 
SOC, PT and relatedness. If the same AE (based on SOC and PT) is reported for the same 
subject more than once, the AE is counted only once for that SOC and PT, and at the highest 
intensity or relatedness, respectively. 
 
In addition, the incidence of SAEs and TEAEs leading to early study termination will be 
presented by SOC and PT. If the same AE (based on SOC and PT) is reported for the same 
subject more than once, the AE is counted only once for that SOC and PT. 
 
Separate listings will be prepared for all AEs, SAEs, AEs leading to early study termination, and 
AEs leading to death. 
 
10.8.3 LABORATORY DATA 
The following types of laboratory assessments will be done in the study: 
 
• 
Safety laboratory assessments (hematology, chemistry, and urinalysis) will be collected 
locally 
• 
CD4 markers will be done centrally for certain countries and locally for others 
• 
Anti-CHOP antibodies will be done centrally 
• 
Inhibitory Factor IX antibodies will be done locally and centrally 
• 
Non-inhibitory Factor IX antibodies will be done centrally 
 
Antibodies data from central lab will be summarized along with 95% exact confidence intervals 
using binomial distribution. 
 
All laboratory assessments (collected locally and centrally) will be listed. 
Thrombogenic markers 
Thrombogenic markers will be done centrally. Results will be summarized and listed. Values 
reported to be above or under upper/lower limits of quantitation will be excluded from the 
summary. In addition, the following tables will be produced 
 
• 
a summary table where these values (reported to be above or under upper/lower limits 
of quantitation) will be treated as being equal to upper/lower limit of quantitation. 
• 
a summary table where these values will be treated as being equal to upper/lower limit 
and excluding a subject whose pre-dose prothrombin fragments 1 + 2 values were 
significantly higher than post-baseline (see Memo to File, “RE: ZA509-0001 efficacy 
assessment”,17 Feb 2023). 
 
 
10.8.4 VITAL SIGNS AND OTHER SAFETY PARAMETERS 
10.8.4.1 VITAL SIGNS 
Descriptive statistics of vital signs (temperature [degree C], systolic and diastolic blood pressure 
[mmHg], pulse rate [beats per minute; bpm] and respiratory rate [breaths/min]) at each 
scheduled visit, as well as the change from baseline will be presented. Summary will be 
prepared for all assessments excluding those made during surgery. Data collected during 
surgery will be listed. 


Statistical Analysis Plan: APVO101-903 
Review Status: Final 
Version: Version 2.1 
Version Date: 23-MAR-2023 
CONFIDENTAL 
Page 21 of 26 
 
 
 
All vital signs data will be presented in a by-subject listing. 
 
10.8.4.2 BLEEDING EPISODES 
Bleeding episode location, cause and side of bleed will be summarized on by-episode level 
cumulative at 50ED and 100ED. 
 
10.8.4.3 PHYSICAL EXAMINATION 
Listing of physical examination findings will be provided by subject. 
 
10.9 OTHER ENDPOINTS AND ANALYSIS 
10.9.1 GENOTYPES 
Mutation genotypes of subjects whose mutations are known at screening and those whose who 
undergo genotyping during the study will be listed. The available genotypes are: 
 
• 
Missense 
• 
Nonsense 
• 
Synonymous 
• 
Large structure change (>50 base pairs [bp]) 
• 
Small structure change (in-frame, <50bp) 
• 
Frameshift 
• 
Promoter 
• 
Splice site change 
11. 
INTERIM ANALYSIS 
When a sufficient number of subjects completes their 50 ED visit, available PK and 
safety/efficacy data (for at least 50 ED) will be included for data analysis of an integrated 
pediatric report for United States post-marketing requirement. 
 
The summaries presenting all efficacy, safety, and PK endpoints listed in Section 10 will be 
included into interim analysis. 
 
All data collected in the study by the time of interim analysis will be listed. 
 
12. 
DEVIATIONS FROM ANALYSIS AS DESCRIBED IN THE 
PROTOCOL 
Protocol version 3.0 amendment 2.0 section 11.4.2. ‘Efficacy analysis specifies: 
 
The annualized bleeding rate will be calculated and summarized, including the 
median, interquartile range and the 95% exact confidence interval for the median, 
assuming that the rates follow a Poisson distribution. 
Sponsor confirmed that the wrong word has been used in this statement due to oversight. 95% 
confidence intervals are planned to be derived for mean (not median), analyzed in the same 
manner as the previous IB1001 studies. 
 
Additional analysis of normalized (square-root transformed) ABR was also added to the efficacy 


Statistical Analysis Plan: APVO101-903 
Review Status: Final 
Version: Version 2.1 
Version Date: 23-MAR-2023 
CONFIDENTAL 
Page 22 of 26 
 
 
 
analysis to provide data comparable to results from studies IB1001-01 and IB1001-02. 
 
According to the protocol, efficacy endpoints are evaluated for the Treatment and Continuation 
phases of the study (section 11.2.2). The Treatment phase begins after PK phase assessments 
are completed (section 5.7). The sponsor clarified that the evaluation of APVO101 efficacy with 
respect to prevention of breakthrough bleeding and with respect to control of hemorrhaging in 
pediatric patients, should be assessed after the initial infusion of APVO101 (PK phase) as this 
first infusion of 75 IU/kg is intended to protect subjects prophylactically. Therefore, any bleeding 
episode that occurs during the PK phase, will be evaluated and considered as belonging to the 
Treatment phase. 
 
13. PROGRAMMING SPECIFICATIONS 
All outputs will be produced using SAS version 9.4 or a later version. 
 
The margins should be at least 1.50 inches for the binding edge and 1.0 inches for all others. 
 
In the top left portion of each output the protocol number and deliverable type will be presented. 
In the top right the company name and page number will be presented. In the next line 3 lines, 
centre-adjusted the table/listing number, title and population information will be displayed. 
Footnotes will be placed under the main body at the bottom of the page. There should be one 
blank line between table content and the footnotes. The SAS program name and its location and 
creation date will appear bottom left. The source listing number or analysis data set name will 
appear on the bottom left corner of each output. The database cut-off/database lock date along 
with outputs status (Draft/Final) will appear just below the source listing. 
 
Tables and listings (no figures are planned in the study) will be provided to Sponsor as two .pdf 
files each of them containing all tables and all listings. In addition the same files as .docx files 
will be provided to PSI medical writing to facilitate CSR writing. 
 
14. LIST OF TABLES AND LISTINGS 
Shells for tables and listings are provided in a separate mock-up TLs document. 


Review Status: Final 
Version: Version 2.1 
Statistical Analysis Plan: APVO101-903 
CONFIDENTAL 
Page 23 of 26 
 
 
15. 
APPENDIX I. SCHEDULE OF ASSESSMENTS 
Version Date: 23-MAR-2023 
 
Screening12 
PK Phase 
Treatment Phase 
Continuation Phase 
End of Study or 
Early 
Termination 
5 
ED 
(±1 
ED) 
12 
ED 
(±2 
ED) 
25 
ED 
(±3 
ED) 
50 
ED 
(±5 
ED) 
75 
ED 
(±5 
ED) 
100 
ED 
(±5 
ED) 
Every 3 
months (~25 
ED ±5 ED) 
Evaluations 
Pre- 
infusion1 
Post- 
infusion2 
Informed consent and/or 
assent 
X 
Eligibility Criteria Review 
X 
Medical and hemophilia- 
related history 
X 
X 
Demographics (age, sex) 
X 
Factor IX mutation 
assessment 
X10 
Concomitant medications 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Physical exam, body weight 
and height 
X 
X 
X 
X 
X 
X 
X 
X 
Vital signs 
X 
X 
X3 
X 
X 
X 
X 
X 
X 
Thrombogenic markers14 
X14 
X4,14 
CBC with differential 5 
X 
X15 
X15 
X15 
X15 
X15 
X15 
CD4 count13 
X 
Serum chemistry6 
X 
X15 
X15 
X15 
X15 
X15 
X15 
Inhibitor titer and non- 
inhibitory factor IX binding 
antibodies9 
X 
X9 
X 
X 
X 
X 
X 
X 
X 
X 


Statistical Analysis Plan: APVO101-903 
Review Status: Final 
Version: Version 2.1 
Version Date: 21-MAR-2023 
CONFIDENTAL 
Page 24 of 26 
 
 
Screening12 
PK Phase 
Treatment Phase 
Continuation Phase 
End of Study or 
Early 
Termination 
5 
ED 
(±1 
ED) 
12 
ED 
(±2 
ED) 
25 
ED 
(±3 
ED) 
50 
ED 
(±5 
ED) 
75 
ED 
(±5 
ED) 
100 
ED 
(±5 
ED) 
Every 3 
months (~25 
ED ±5 ED) 
Evaluations 
Pre- 
infusion1 
Post- 
infusion2 
Anti-CHOP antibodies 
X 
X16 
X 
X 
X 
X 
X 
X 
X 
X 
Assessment of major and/or 
target joints 
X 
X 
X 
X 
Urinalysis7 
X 
X 
X 
X 
X 
X 
X 
Factor IX activity11 
X 
X 
Adverse events 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Efficacy/subject diary8 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Training on subject diary and 
APVO101 reconstitution and 
administration 
X 
1 From 2 hours to 15 minutes pre-infusion. 
2 At 15-30 minutes, 4-6 hours, 24-26 hours and 46-50 hours post-infusion of 75 ± 5 IU/kg (PK dose). 
3 Vital signs (pulse rate, blood pressure, respiratory rate and temperature) at 15-30 minutes, 4-6 hours, 24-26 hours and 46-50 hours post-infusion of PK dose. 
4 Thrombogenicity marker assessments at 15-30 minutes, 4-6 hours and 24-26 hours post-infusion of PK dose. 
5 Includes hemoglobin, hematocrit, absolute counts of: white blood cells, neutrophils, monocytes, lymphocytes, eosinophils, basophils, platelets and red blood 
cells; mean platelet volume (MPV), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration 
(MCHC) to be assessed at a local laboratory. 
6 Includes ALT, AST, ALP, BUN or urea, uric acid, creatinine, total bilirubin and glucose to be assessed at a local laboratory. 
7 Urine dipstick, followed by microscopy if abnormal to be assessed at a local laboratory. 
8 Investigator’s efficacy assessment and review of subject’s diary including infusions, bleeding summary, subject’s efficacy assessment, adverse events and 
concomitant medications. At Screening, review of subject diary to include review of previous factor IX therapy (if available). 
9 Inhibitory and non-inhibitory factor IX antibodies to be assessed by central lab at PK Phase Pre-infusion for subjects weighing ≥ 28 kg, and all subjects at all 
other time points. 
10 Factor IX mutation assessment to include mutation genotyping by central laboratory if not previously documented. For patients below 10 kg this may be done 


Statistical Analysis Plan: APVO101-903 
Review Status: Final 
Version: Version 2.1 
CONFIDENTAL 
Page 25 of 26 
 
 
Version Date: 21-MAR-2023 
at any time during the study when blood volumes allow 
11 Factor IX activity to be assessed by central lab pre-infusion and post-infusion at 15-30 minutes, 4-6 hours, 24-26 hours, and 46-50 hours. Pre-infusion and 
15 to 30 minutes post-infusion samples will be tested for factor IX activity to determine the starting prophylaxis dose. See protocol section 5.7.1 for further 
details. 
12 Screening to occur 21 to 5 days prior to PK phase. 
13 CD4 count to be assessed by local laboratory. 
14 See protocol Table 2 for thrombogenicity assessments by subject weight; thrombogenicity markers include D-dimer, TAT complex, fragment 1+2. 
15 For patients below 17 kg, CBC with differential and serum chemistry should be collected if blood volumes allow. 
16 Anti-CHOP antibodies to be assessed by central laboratory at PK phase pre-infusion for subjects weighing ≥ 28 kg 
 
Table 1: Thrombogenicity Assessments During PK Phase by Subject Weight 
 
Subject weight 
Pre-infusion 
15-30 min post-infusion 
4-6 hours post-infusion 
24-26 hours post-infusion 
≥ 20 kg 
X 
X 
X 
X 
≥ 17 kg to <20kg 
X 
X 
X 
<17 kg1 
1 To accommodate blood volume limitations for subjects <17 kg, no thrombogenicity assessments will be performed during the PK Phase. Thrombogenicity 
assessments may be drawn at these timepoints during the Treatment Phase when blood volume limitations allow. 
 
 
Table 2: Schedule of Events for a Surgical Procedure (if required during Treatment Phase and/or Continuation Phase) 
 
Prior to surgery1 
During 
surgery 
End of 
surgery 
12 hours post- 
surgery 
24 hours post- 
surgery2 
28 days (±7 days) post- 
factor IX replacement 
therapy for surgery 
Evaluations 
Pre- 
infusion 
Post- 
infusion (5- 
30 min) 
Pre- 
infusion 
Post- 
infusion 
(5-30 
min) 
Pre- 
infusion 
Post- 
infusion 
(5-30 
min) 
Factor IX activity3 
X 
X 
X4 
X 
X 
X 
X 
Vital signs 
X 
X 
X 
Adverse events 
X 
X 
X 
X 
X 


Statistical Analysis Plan: APVO101-903 
Review Status: Final 
Version: Version 2.1 
Version Date: 21-MAR-2023 
CONFIDENTAL 
Page 26 of 26 
 
 
Prior to surgery1 
During 
surgery 
End of 
surgery 
12 hours post- 
surgery 
24 hours post- 
surgery2 
28 days (±7 days) post- 
factor IX replacement 
therapy for surgery 
Evaluations 
Pre- 
infusion 
Post- 
infusion (5- 
30 min) 
Pre- 
infusion 
Post- 
infusion 
(5-30 
min) 
Pre- 
infusion 
Post- 
infusion 
(5-30 
min) 
Use of blood products 
X 
X 
X 
X 
X 
Surgeon’s assessment of 
expected/estimated blood 
loss 
X 
X 
X 
X 
1 If using bolus infusions, an infusion of up to 120 IU/kg will be given within 1 hour prior to the start of the procedure, followed by an infusion of approximately 
60 IU/kg 12 hours after the first infusion and an infusion of up to 120 IU/kg 24 hours after the first infusion. If administering a continuous infusion, the plasma 
factor IX activity should range between 70% and 110%, and the dose and timing of subsequent infusions and adjustments should be recorded and guided by 
factor IX activity results. 
2 Continue with bolus or continuous infusion treatment for as long as the surgeon deems necessary, but for a minimum of 3 days post-surgery for major surgery or a 
minimum of 1 day post-procedure for minor surgery. Assess pre- and post-infusion factor IX activity every 12 hours. 
3 Factor IX activity is to be assessed by the local laboratory at all time points. If blood volumes allow, factor IX samples should also be assessed by the central 
laboratory. 
4 If study product is infused during surgery, measure factor IX activity pre- and post-infusion (5-30 minutes).