First Patient Screened in CSL Behring Global Phase I/III Study of Recombinant Single-Chain Factor VIII

VIENNA, Feb. 24, 2012 /PRNewswire/ -- CSL Behring has announced that the first patient has been screened in its recombinant coagulation single-chain factor VIII (rFVIII) trial, part of the AFFINITY clinical trial program. The CSL Behring rFVIII, called 'rVIII-SingleChain', is a novel molecule being studied for the treatment of hemophilia A. It is being developed by CSL Behring, in collaboration with its parent company, CSL Limited (ASX: CSL).

"CSL is advancing at a very encouraging rate with our recombinant coagulation factor development program," said Dr. Andrew Cuthbertson, Chief Scientist CSL Limited. "Our ongoing commitment to providing safe and effective therapies to help improve the lives of those affected by hemophilia A and other rare bleeding disorders is being fulfilled with each milestone we reach. Our recombinant coagulation single-chain factor VIII molecule is showing strong promise. We look forward with excitement to seeing results of the phase I/III study in coming months."

About the AFFINITY Phase I/III Study
The Phase I/III study is an open-label, multicenter trial that examines the crossover safety, efficacy and pharmacokinetics of recombinant coagulation single-chain factor VIII compared with recombinant human antihemophilic factor VIII (octocog alpha). 

In Part 1 of the study, subjects will receive a single infusion of 50 IU/kg of octocog alpha followed by a single infusion of 50 IU/kg. In Parts 2 and 3 of the study, subjects will receive infusions of rVIII-SingleChain to prevent and treat bleeding (if required), at a dose and frequency determined by their study doctor (based on the subject's underlying bleeding phenotype). More information about the study design can be found at www.clinicaltrials.gov.  

Recombinant single-chain factor VIII consists of two linked protein chains – a heavy one and a light one. Under certain conditions, these chains can dissociate, resulting in the formation of separated, or "dissociated," rFVIII chains. The CSL Behring rVIII-SingleChain uses a strong, covalent bond that connects the light and heavy chains, thereby creating a single chain rFVIII.

In-house studies 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. In addition, in-vitro studies have shown that rVIII-SingleChain demonstrates a very strong affinity for von Willebrand factor, resulting in a faster and more efficient binding to VWF. 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.

The research leading to the initiation of the studies that CSL Behring is now conducting is the result of collaboration across the CSL Behring research sites in Marburg, Germany, in King of Prussia, USA, and at laboratories operated by CSL Limited in Melbourne, Australia.

About Hemophilia
Hemophilia is a congenital bleeding disorder characterized by prolonged or spontaneous bleeding, especially into the muscles, joints, or internal organs. In nearly all cases, it affects only males. The disease is caused by deficient or defective blood coagulation proteins known as factor VIII or IX. The most common form of the disease is hemophilia A, or classic hemophilia, in which the clotting factor VIII is either deficient or defective. Hemophilia B is characterized by deficient or defective factor IX. Hemophilia A affects approximately 1 in 5,000 to 10,000 people. Hemophilia B affects approximately 1 in 25,000 to 50,000 people. The recommended treatment for patients who are factor deficient is to treat by replacement factor therapy. A complication in some patients is the development of inhibitory antibodies (inhibitors) to FVIII or FIX which renders replacement therapy ineffective. This can occur in up to 25 percent of hemophilia A patients and around 5 percent of hemophilia B patients. One treatment option for these patients is recombinant activated factor VII (called a bypassing agent) that can be used to achieve hemostasis without the need for factor VIII or IX.

About CSL Behring
CSL Behring is a leader in the plasma protein therapeutics industry. Committed to saving lives and improving the quality of life for people with rare and serious diseases, the company manufactures and markets a range of plasma-derived and recombinant therapies worldwide. CSL Behring therapies are indicated for the treatment of coagulation disorders including hemophilia and von Willebrand disease, primary immune deficiencies, hereditary angioedema and inherited respiratory disease. The company's products are also used in cardiac surgery, organ transplantation, burn treatment and to prevent hemolytic diseases in newborns. CSL Behring operates one of the world's largest plasma collection networks, CSL Plasma. CSL Behring is a subsidiary of CSL Limited (ASX:CSL), a biopharmaceutical company headquartered in Melbourne, Australia. For more information, visit www.cslbehring.com

SOURCE CSL Behring