Study site for this first enrollment is Malaysia. The Phase III study has been designed to evaluate the safety, efficacy and pharmacokinetics of its rVIII-SingleChain for the treatment of previously treated children (up to age 11 years) with severe hemophilia A.
The Phase III pivotal study is expected to enroll a minimum of 25 previously treated subjects from six to 11 years of age and at least 25 subjects under six years of age who have undergone more than 50 exposure days with a previous factor VIII product.
In this multicenter, open-label study, subjects will be assigned to either an on-demand or prophylaxis treatment regimen for the treatment of bleeding episodes and will receive rVIII-SingleChain at a dose to be determined by the investigator.
Hemostatic efficacy will be assessed by the subject or caregiver and the investigator, who will assess overall efficacy by a four-point scale.
CSL Behring’s rVIII-SingleChain has demonstrated improved pharmacokinetics over the comparator octocog alfa in an earlier study. rVIII-SingleChain demonstrated a safety and efficacy profile that supported advancement to late-stage clinical development.
According to CSL Behring, rVIII-SingleChain uses a strong, covalent bond that connects the light and heavy chains, thereby creating a stable single chain rFVIII.
The company’s in-house have shown that the molecular integrity of rVIII-SingleChain is significantly increased using the single-chain design, resulting in a homogenous product that is more stable than currently available FVIII products.
Additionally, in-vitro studies have shown that rVIII-SingleChain demonstrates a strong affinity for von Willebrand factor, resulting in a faster and more efficient binding to VWF.
According to CSL Behring, the FVIII/VWF complex plays an important role in the physiological activity and clearance of FVIII and has been shown to have an influence on the presentation of FVIII to the immune system.
In collaboration with its parent company CSL, CSL Behring is developing rVIII-SingleChain for the treatment of hemophilia A as part of the AFFINITY clinical trial program.