Study to Evaluate the Safety, Efficacy, and Pharmacokinetics of Recombinant Coagulation Factor VIII Fc Fusion Protein (rFVIIIFc) in Previously Treated Pediatric Subjects With Hemophilia A

Study Overview
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Brief Summary
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The primary objective of the study is to evaluate the safety of Recombinant Coagulation Factor VIII Fc Fusion Protein (rFVIIIFc) in previously treated pediatric subjects with hemophilia A. Secondary objectives of this study in this study population are as follows: to evaluate the efficacy of rFVIIIFc for prevention and treatment of bleeding episodes; to evaluate and assess the pharmacokinetics (PK) of rFVIIIFc; and to evaluate rFVIIIFc consumption for prevention and treatment of bleeding episodes.

Detailed Description
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Previously treated pediatric participants will be treated with a prophylactic regimen of rFVIIIFc. PK analysis of pre-study factor VIII (FVIII) and rFVIIIFc will be performed in a sub-group of the study participants prior to commencement of prophylactic treatment. After these PK results are available, remaining participants have the option of proceeding directly to prophylactic treatment. After completing the end of study assessments, eligible participants would be able to continue treatment in Study 8HA01EXT.

Official Title
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An Open-Label, Multicenter Evaluation of Safety, Pharmacokinetics, and Efficacy of Recombinant Coagulation Factor VIII Fc Fusion Protein, BIIB031, in the Prevention and Treatment of Bleeding Episodes in Pediatric Subjects With Hemophilia A

Conditions
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Hemophilia A

Intervention / Treatment
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* Drug: BIIB031 (rFVIIIFc)
* Drug: FVIII (PK subgroup only)


Participation Criteria
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Eligibility Criteria
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Key Inclusion Criteria: Severe hemophilia A defined as <1 IU/dL (<1%) endogenous FVIII Male <12 years of age and weight ≥13 kg History of at least 50 documented prior exposure days to FVIII No current, or history of, inhibitor development to FVIII Key Exclusion Criteria: Other coagulation disorders in addition to Hemophilia A History of anaphylaxis associated with any FVIII or IV immunoglobulin administration NOTE: Other protocol-defined Inclusion/Exclusion criteria may apply.

Ages Eligible for Study
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Maximum Age: 11 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: All participants<br>PK subgroup: After a Washout Period of ≥72 hours, at the Baseline Visit (28±7 days prior to Day 1), participants receive a single IV injection of prestudy FVIII over 5 (±2) minutes at a dose of 50 IU/kg, rounded up to the nearest 250 IU increment, for a PK assessment. Following a second Washout Period of ≥72 hours, participants receive a single IV injection of rFVIIIFc over 5 (±2) minutes at a dose of 50 IU/kg for PK assessment. The first prophylactic dose of rFVIIIFc is administered at a starting dose of 25 IU/kg IV injection on Day 1 and 50 IU/kg on Day 4. Dose increases to a maximum of 80 IU/kg, and frequency of administration to a minimum interval of once every 2 days, are allowed as indicated. Non-PK subgroup: On Day 1, a first prophylactic dose of rFVIIIFc of 25 IU/kg IV injection is given, followed by a dose of 50 IU/kg on Day 4. Dose increases to a maximum of 80 IU/kg, and frequency of administration to a minimum interval of once every 2 days, are allowed as indicated. | Drug: BIIB031 (rFVIIIFc)<br>* Vials of rFVIIIFc were combined as needed, based on the actual labeled potency to achieve the participant's calculated dose. Partial vial use was allowed, in order to achieve the calculated dose.<br>* Other names: recombinant coagulation factor VIII Fc fusion protein;Drug: FVIII (PK subgroup only)<br>* Baseline prestudy FVIII dosing in participants who enter the PK subgroup. Vials of prestudy FVIII were combined as needed, based on the nominal labeled potency (e.g., 250 IU, 500 IU, and 1000 IU), to achieve the participant's calculated dose.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Occurrence of FVIII Inhibitor Development | An inhibitor test result ≥0.6 Bethesda units (BU)/mL, confirmed on 2 separate samples drawn 2 to 4 weeks apart, was considered positive. Both tests were to be performed by the central laboratory using the Nijmegen-modified Bethesda Assay. Incidences were summarized for any positive inhibitor for participants with ≥50 EDs to rFVIIIFc. In addition, the incidence for all participants, regardless of their EDs to rFVIIIFc, was also summarized. An exact 95% CI for the proportion of participants with a confirmed inhibitor was calculated using the Clopper-Pearson exact method for a binomial proportion. | Up to Week 26 +/- 7 days, or up to 50 exposure days (EDs) if reached prior to Week 26 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Annualized Bleeding Rate | Annualized bleeding rate = (number of bleeding episodes during the efficacy period / total number of days during the efficacy period)*365.25. The efficacy period begins with the first prophylactic dose of rFVIIIFc and ends with the last dose (for prophylaxis or a bleed). Surgery/rehabilitation periods and PK evaluation periods are not included in the efficacy period. A bleeding episode started from the first sign of a bleed and ended no more than 72 hours after the last treatment for the bleed, within which any symptoms of bleeding at the same location or injections less than or equal to 72 hours apart were considered the same bleeding episode. Any injection to treat the bleeding episode taken more than 72 hours after the preceding one was considered the first injection to treat a new bleeding episode at the same location. Any bleeding at a different location was considered a separate bleeding episode, regardless of time from last injection. | Up to Week 26 +/- 7 days (efficacy period as defined in description) | 
| Annualized Joint Bleeding Rate (Spontaneous) | Annualized bleeding rate for spontaneous joint bleed=(number of bleeding episodes meeting those criteria during the efficacy period/total number of days during the efficacy period)*365.25. The efficacy period begins with the first prophylactic dose of rFVIIIFc and ends with the last dose (for prophylaxis or a bleed). Surgery/rehabilitation periods and PK evaluation periods are not included in the efficacy period. A bleeding episode started from the first sign of a bleed and ended no more than 72 hours after the last treatment for the bleed, within which any symptoms of bleeding at the same location or injections less than or equal to 72 hours apart were considered the same bleeding episode. Any injection to treat the bleeding episode taken more than 72 hours after the preceding one was considered the first injection to treat a new bleeding episode at the same location. Any bleeding at a different location was considered a separate bleeding episode, regardless of time from last inject | Up to Week 26 +/- 7 days (efficacy period as defined in description) | 
| Participant Assessment of Response to Injections to Treat a Bleeding Episode | Participant's assessment (provided by the caregiver) of the response to the first rFVIIIFc injection for each bleeding episode. Percentages were based on the number of first injections for which a response was provided, using the following 4-point scale: excellent=abrupt pain relief and/or improvement in signs of bleeding within approximately 8 hours after the initial injection; good=definite pain relief and/or improvement in signs of bleeding within approximately 8 hours after a single injection, but possibly requiring more than one injection after 24 to 48 hours for complete resolution; moderate=probable or slight beneficial effect within approximately 8 hours after the initial injection and requiring more than one injection; no response=no improvement, or condition worsened, within approximately 8 hours after the initial injection. | Up to Week 26 +/- 7 days | 
| Physician's Global Assessment of the Participant's Response to His rFVIIIFc Regimen | Investigators assessed each participant's response to his rFVIIIFc regimen using a 4-point scale: excellent=bleeding episodes responded to ≤ the usual number of injections or ≤ the usual dose of rFVIIIFc or the rate of breakthrough bleeding during prophylaxis was ≤ that usually observed; effective=most bleeding episodes responded to the same number of injections and dose, but some required more injections or higher doses, or there was a minor increase in the rate of breakthrough bleeding; partially effective=bleeding episodes most often required more injections and/or higher doses than expected, or adequate breakthrough bleeding prevention during prophylaxis required more frequent injections and/or higher doses; ineffective=routine failure to control hemostasis, or hemostatic control required additional agents. Percentages are based on the total number of responses; multiple responses per participant are counted. | Up to Week 26 +/- 7 days | 
| Annualized rFVIIIFc Consumption Per Participant | Consumption is calculated for the efficacy period. The efficacy period begins with the first prophylactic dose of rFVIIIFc and ends with the last dose (for prophylaxis or a bleed). Surgery/rehabilitation periods and PK evaluation periods are not included in the efficacy period. Annualized consumption = (total IU/kg of study treatment received during the efficacy period / total number of days during the efficacy period)*365.25. Consumption was calculated overall for all participants and for the last 3 months (91 days) on study, counted backwards from the end of the efficacy period, for participants with at least 24 weeks on study. | Up to Week 26 +/- 7 days (efficacy period as defined in description) | 
| Number of Days From Last Treatment Injection to a Spontaneous Bleeding Episode | The number of days from the last prophylaxis injection to the onset of a new spontaneous bleeding episode, analyzed across all evaluable bleeding episodes per participant and per episode, based on the efficacy period. Evaluable bleeding episodes are those for which both a date and time are available for both the onset of the bleeding episode and the previous prophylactic injection. The efficacy period begins with the first prophylactic dose of rFVIIIFc and ends with the last dose (for prophylaxis or a bleed). Surgery/rehabilitation periods and PK evaluation periods are not included in the efficacy period. For 'Per participant' values, the number of days from the last prophylactic injection to a spontaneous bleeding episode is averaged across all evaluable spontaneous bleeding episodes per participant. | Up to Week 26 +/- 7 days (efficacy period as defined in description) | 
| Number of Injections Required for Resolution of a Bleeding Episode | The number of injections required to resolve a bleeding episode per participant and per episode, based on the efficacy period. The efficacy period begins with the first prophylactic dose of rFVIIIFc and ends with the last dose (for prophylaxis or a bleed). Surgery/rehabilitation periods and PK evaluation periods are not included in the efficacy period. All injections given from the initial sign of a bleed, until the last date/time within the bleed window are counted. The resolution of a bleed is defined as no sign of bleeding following injection for the bleed. For 'Per participant' values, the number of injections required to resolve each bleed is averaged across all bleeding episodes per participant. | Up to Week 26 +/- 7 days (efficacy period as defined in description) | 
| Total Dose Required for Resolution of a Bleeding Episode | The total dose required to resolve a bleeding episode per participant and per episode, based on the efficacy period. The efficacy period begins with the first prophylactic dose of rFVIIIFc and ends with the last dose (for prophylaxis or a bleed). Surgery/rehabilitation periods and PK evaluation periods are not included in the efficacy period. For 'Per bleeding episode' values, for each bleeding episode, the total dose is the sum of the doses (IU/kg) administered across all injections given to treat that bleeding episode. For 'Per participant' values, the total dose (IU/kg) used to resolve each bleed is averaged across all bleeding episodes per participant. | Up to Week 26 +/- 7 days (efficacy period as defined in description) | 
| Maximum Plasma Activity (Cmax; One-stage Activated Partial Thromboplastin Time [aPTT] Clotting Assay) | Maximum plasma activity during a dosing interval for participants in the PK subgroup. The values for Cmax were adjusted to the nominal dose of 50 IU/kg. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Maximum Plasma Activity (Cmax; Two-stage Chromogenic Assay) | Maximum plasma activity during a dosing interval for participants in the PK subgroup. The values for Cmax were adjusted to the nominal dose of 50 IU/kg. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Elimination Half Life (t1/2; One-stage aPTT Clotting Assay) | Time required for the activity of the drug to reach half of its original value for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Elimination Half Life (t1/2; Two-stage Chromogenic Assay) | Time required for the activity of the drug to reach half of its original value for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Clearance (CL; One-stage aPTT Clotting Assay) | Rate at which the body removes the drug, measured as the volume of the plasma cleared of drug per unit time per unit weight for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Clearance (CL; Two-stage Chromogenic Assay) | Rate at which the body removes the drug, measured as the volume of the plasma cleared of drug per unit time per unit weight for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Volume at Steady State (Vss; One-stage aPTT Clotting Assay) | Volume of distribution at steady state for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Volume at Steady State (Vss; Two-stage Chromogenic Assay) | Volume of distribution at steady state for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Dose Normalized Area Under the Curve (DNAUC; One-stage aPTT Clotting Assay) | Dose normalized area under the FVIII activity-time curve for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Dose Normalized Area Under the Curve (DNAUC; Two-stage Chromogenic Assay) | Dose normalized area under the FVIII activity-time curve for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Mean Residence Time (MRT; One-stage aPTT Clotting Assay) | The average time that a drug molecule is present in the systemic circulation for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Mean Residence Time (MRT; Two-stage Chromogenic Assay) | The average time that a drug molecule is present in the systemic circulation for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Incremental Recovery (IR; One-stage aPTT Clotting Assay) | The rise in FVIII activity in IU/dL per unit dose administered in IU/kg for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Incremental Recovery (IR; Two-stage Chromogenic Assay) | The rise in FVIII activity in IU/dL per unit dose administered in IU/kg for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Time at Maximum Activity (Tmax; One-stage aPTT Clotting Assay) | Time at which maximum activity (Cmax) is observed for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Time at Maximum Activity (Tmax; Two-stage Chromogenic Assay) | Time at which maximum activity (Cmax) is observed for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Lambda Z (One-stage aPTT Clotting Assay) | First order rate constant associated with the terminal portion of the curve (lambda z) for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Lambda Z (Two-stage Chromogenic Assay) | First order rate constant associated with the terminal portion of the curve (lambda z) for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Volume at Terminal Phase (Vz; One-stage aPTT Clotting Assay) | Volume of distribution estimated from the terminal phase for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Volume at Terminal Phase (Vz; Two-stage Chromogenic Assay) | Volume of distribution estimated from the terminal phase for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Area Under the Curve to the Last Measurable Timepoint (AUClast; One-stage aPTT Clotting Assay) | Dose-normalized area under the FVIII activity-time curve to the last measurable timepoint for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Area Under the Curve to the Last Measurable Timepoint (AUClast; Two-stage Chromogenic Assay) | Dose-normalized area under the FVIII activity-time curve to the last measurable timepoint for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Area Under the Curve to Infinity (AUCinf; One-stage aPTT Clotting Assay) | Dose normalized area under the FVIII activity-time curve to infinity for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Area Under the Curve to Infinity (AUCinf; Two-stage Chromogenic Assay) | Dose normalized area under the FVIII activity-time curve to infinity for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Percentage of AUCinf Extrapolated From the Last Data Point to Infinity (%AUCext; One-stage aPTT Clotting Assay) | Percentage of AUCinf extrapolated from the last data point to infinity for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose | 
| Percentage of AUCinf Extrapolated From the Last Data Point to Infinity (%AUCext; Two-stage Chromogenic Assay) | Percentage of AUCinf extrapolated from the last data point to infinity for participants in the PK subgroup. The 95% confidence interval on the geometric mean is based on the t-statistic back-transformed from the log scale. | Baseline (28 ±7 days prior to Day 1) Prestudy FVIII Dosing: predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours post-dose. Day 1 (rFVIIIFc Dosing): predose; 30 ±5 min, 3 hours ±30 min, 24 ±3 hours, 48 ±4 hours, 72 ±7 hours post-dose |