U.S. FDA Accepts for Review CSL Behring’s Biologics License Application for Its Novel rVIII-SingleChain Therapy for Patients with Hemophilia A
rVIII-SingleChain underscores CSL Behring’s deep commitment to developing and delivering specialty biotherapies that improve the well-being of patients with serious diseases
KING OF PRUSSIA, Pa. — 28 July 2015
CSL Behring announced today that the U.S. Food and Drug Administration has accepted for review the company’s Biologics License Application (BLA) for its novel investigational recombinant factor VIII single-chain (rVIII-SingleChain) for the treatment of hemophilia A. In the pivotal clinical trial, rVIII-SingleChain met all primary endpoints.
Hemophilia A is a congenital bleeding disorder characterized by deficient or defective factor VIII; nearly all affected patients are male. People with hemophilia A may experience prolonged or spontaneous bleeding, especially into the muscles, joints, or internal organs. The condition affects approximately 1 in 6,000 male births.
“CSL Behring has one of the industry’s largest portfolios of biotherapies that improve the care and well-being of patients with a bleeding disorder,” said Dr. Andrew Cuthbertson, Chief Scientific Officer and Director of R&D, CSL Limited. “Our scientific expertise and relationship with the bleeding disorders community led us to seek further advancements in the care and treatment of hemophilia. Today, we have the only recombinant single-chain factor VIII product in late-stage development for the management of hemophilia A, and we are excited to be one step closer to providing this innovative treatment to patients in the U.S.”
The BLA submission is based on the AFFINITY clinical development program, which includes a phase I/III open-label, multi-center trial examining safety and efficacy. The pharmacokinetics of rVIII-SingleChain compared with recombinant human antihemophilic factor VIII (octocog alfa) was also studied. Study design details for rVIII-SingleChain are available at
Results from the phase I/III study were recently presented at the International Society on Thrombosis and Haemostasis (ISTH) congress in Toronto. Patients treating prophylactically had a median annualized bleeding rate (ABR) of 1.14 and a median annualized spontaneous bleeding rate (AsBR) of 0.00. The data also showed that, of 848 bleeds treated in the study, 94 percent were controlled with no more than two infusions of rVIII-SingleChain, with 81 percent controlled by one infusion. Moreover, hemostatic control of a bleeding event treated with rVIII-SingleChain was assessed by the investigator as excellent or good 94 percent of the time (835 assessed bleeding events).
The results presented included data on more than 14,000 exposure days in 146 patients on prophylaxis and 27 patients treating on demand for a bleeding event. In total, 120 patients were treated for more than 50 days of exposure; 52 had more than 100 days of exposure. In the prophylaxis group, 32 percent of patients were dosed twice weekly and 54 percent received treatment three times per week; the regimen was determined by the investigator. The most common adverse events were naso-pharyngitis, arthralgia, and headache. No inhibitors were reported.
Specifically designed for greater molecular stability, rVIII-SingleChain is the first and only single-chain factor VIII (FVIII) product in late-stage development for the treatment of hemophilia A. rVIII-SingleChain (also known as CSL627) has a strong affinity for von Willebrand factor, leading to greater stability and integrity of FVIII in circulation. For more information about CSL Behring’s recombinant products in development to treat hemophilia, visit
About CSL Behring
The people and science of CSL Behring save lives around the world. We develop and deliver innovative specialty biotherapies, driven by our 100-year promise to help people with life-threatening conditions live full lives. With 14,000 employees and operations in 30 countries, CSL applies world-class R&D, high-quality manufacturing and patient-centered management.
CSL Behring therapies are used around the world to treat coagulation disorders including hemophilia and von Willebrand disease, primary immune deficiencies, hereditary angioedema and inherited respiratory disease, and neurological disorders in certain markets. The company’s products are also used in cardiac surgery, organ transplantation, burn treatment and to prevent hemolytic disease of the newborn.
CSL Behring operates one of the world’s largest plasma collection networks, CSL Plasma. CSL Behring is a global biopharmaceutical company and a member of the CSL Group of companies. The parent company,
CSL Limited (ASX:CSL), is headquartered in Melbourne, Australia. For more information, visit