A Safety, Efficacy and Pharmacokinetics Study of a Recombinant Fusion Protein Linking Coagulation Factor IX With Albumin (rIX-FP) in Children With Hemophilia B

CSL Behring27 enrolled

Overview

This study will examine the pharmacokinetics, safety and efficacy of rIX-FP for the control and prevention of bleeding episodes in children who have previously received factor replacement therapy for hemophilia B.

Study Type

INTERVENTIONAL

Allocation

Purpose

TREATMENT

Masking

NONE

Enrollment

Conditions

Hemophilia B

Interventions

rIX-FPBIOLOGICAL

Recombinant Fusion Protein Linking Coagulation Factor IX with Albumin (rIX-FP)

Eligibility

Sex: MALEMax age: 11 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Male subjects, younger than 12 years old. * Severe hemophilia B (Factor IX \[FIX\] activity of ≤ 2%). * Body weight ≥ 10 kg. * Subjects who have received FIX products (plasma-derived and/or recombinant FIX) for \> 150 exposure days (EDs) (6 to \< 12 years), and \> 50 EDs (\< 6 years). * No history of FIX inhibitor formation, no detectable inhibitors at Screening and no family history of inhibitors against FIX. * Written informed consent for study participation. Exclusion Criteria: * Known hypersensitivity to any FIX product or hamster protein. * Known congenital or acquired coagulation disorder other than congenital FIX deficiency. * Kidney or liver disease. * Recent life-threatening bleeding episode.

Locations (17)

The Royal Children's Hospital, Melbourne

Parkville, Victoria, Australia

The Children's Hospital at Westmead

Westmead, Australia

Outcomes

Primary Outcomes

Incremental Recovery Following a Single Intravenous Dose of 50 IU/kg rIX-FP or Previous FIX Product

Incremental recovery (IU/dL/IU/kg) is defined as the FIX activity (IU/dL) obtained 30 minutes following infusion, per dose of (IU/kg) infusion. FIX activity was measured at a central laboratory using validated one-stage clotting method. Recovery values were baseline-corrected for pre-infusion plasma FIX activity. Incremental recovery was measured following a single intravenous dose of 50 IU/kg rIX-FP on Day 1. Analysis of previous FIX product was conducted at the beginning of the study in a subset of subjects who had no historical pharmacokinetic (PK) data of their previous FIX product. For the PK assessment, the previous FIX product was administered by IV infusion after approximately 4 days following the last FIX treatment, prior to any dosing of rIX-FP. The formal PK population consisted of subjects who received at least 1 dose of rIX-FP for PK assessment and for whom a sufficient number of analyzable PK samples had been obtained to permit the evaluation of the PK profile of rIX-FP.

Time frame: 30 minutes after infusion

Half-life (t1/2) Following a Single Intravenous Dose of 50 IU/kg rIX-FP or Previous FIX Product

FIX activity was measured at a central laboratory using validated one-stage clotting method. FIX levels were not corrected for baseline values.

Time frame: Pre-dose, 30 minutes, 3, 24, 48, 72 120, 168, 240 and 336 hours post-dose

Area Under the Concentration Versus Time Curve From Time Point Zero to the Last Sample With Quantifiable Drug Concentration (AUClast)

AUClast following a single intravenous dose of 50 IU/kg rIX-FP or previous FIX product. FIX activity was measured at a central laboratory using validated one-stage clotting method. FIX levels were not corrected for baseline values.

Time frame: Pre-dose, 30 minutes, 3, 24, 48, 72 120, 168, 240 and 336 hours post-dose

Clearance for FIX Activity Following a Single Intravenous Dose of 50 IU/kg rIX-FP or Previous FIX Product

FIX activity was measured at a central laboratory using validated one-stage clotting method. FIX levels were not corrected for baseline values. Clearance is normalized for body weight.

Data from ClinicalTrials.gov

This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.

Secondary Outcomes

Number of Subjects With Treatment-related Adverse Events

Time frame: 12 months

Number of Subjects Developing Antibodies Against rIX-FP

Antibodies to rIX-FP were measured using a direct-binding enzyme-linked immunosorbent assay (ELISA).

Time frame: 12 months

Number of Bleeding Episodes Requiring One, Two or More Than Two Infusions of rIX-FP to Achieve Hemostasis

For each bleeding episode that required treatment, the number of episodes that required one, two or more than two infusions of rIX-FP to achieve hemostasis

Time frame: Approximately 12 months

Consumption of rIX-FP During Routine Prophylaxis

Consumption of rIX-FP during routine prophylaxis is expressed as the total prophylaxis dose per month.

Time frame: 12 months