Baxter International Inc has signed an agreement with Kaketsuken, the Chemo-Sero-Therapeutic Research Institute, based in Kumamoto Japan, for the worldwide rights to develop, manufacture and market the recombinant protein Adamts13.

The development of recombinant Adamts13, a bio-engineered version of a naturally occurring enzyme that plays a critical role in blood coagulation, will strengthen Baxter's pre-clinical research and development pipeline for specialty therapeutics targeting rare diseases. In the absence of Adamts13 in the blood, patients develop a severe, often life-threatening condition called thrombotic thrombocytopenic purpura (TTP), marked by the formation of platelet-rich blood clots in blood vessels throughout the body. Recombinant Adamts13 is being developed for the treatment of TTP and related disorders and will be evaluated for other indications in the future. This agreement provides an opportunity for Baxter to exclusively develop a new recombinant protein and investigate its potential use in treating unmet medical needs.

"We are very excited to add recombinant Adamts13 to our development pipeline. Elucidating the role of recombinant Adamts13 in TTP and other blood-clotting disorders might provide us with a new treatment modality for thrombotic diseases, which is a substantial addition to our R&D pipeline," said Hartmut J. Ehrlich, M.D., vice president, Global Research and Development, Baxter's BioScience business.

When a blood vessel is injured, a platelet plug is formed that adheres to the injury site and reduces or stops the bleeding. Platelet adherence is mediated by naturally occurring von Willebrand factor (VWF), a large protein found in the circulating blood, and naturally occurring Adamts13, an enzyme that plays a critical role in haemostasis by actively regulating the function of VWF.

Under the terms of this agreement, Kaketsuken will provide Baxter with access to Kaketsuken's intellectual property rights concerning the recombinant protein. Baxter has an exclusive license to the recombinant Adamts13 intellectual property rights worldwide, except for Japan where Baxter has a co-exclusive license to commercialise recombinant Adamts13 with Kaketsuken. In addition to an upfront payment upon signing the agreement, Baxter will pay Kaketsuken milestone payments upon Investigational New Drug (IND) filing, initiation of phase II and phase III trials, Biologics License Application (BLA) filings and US Food and Drug Administration approval of recombinant Adamts13.

The inclusion of Adamts13 in Baxter's pre-clinical portfolio fits into the company's platform of specialty pharmaceuticals. Baxter has pioneered protein therapies developed from the separation and purification of important blood components and recombinant technologies, applying its knowledge and resources to become a leader in blood-related disorders such as haemophilia and other immune deficiencies. Baxter is recognized as a global leader in haemophilia therapies with a growing portfolio of innovative therapies and technologies, developed through strategic collaborations and internal research and development.

TTP is a thrombotic disorder that is caused by the formation of platelet-rich thrombi in blood vessels throughout the body. Hereditary TTP, also known as Upshaw Schulman syndrome, is caused by detrimental mutations of the ADAMTS13 gene, resulting in severe Adamts13 deficiency, whereas acquired TTP is often due to auto-antibodies directed against Adamts13. Characterized by bruising, anemia, fever, neurological abnormalities and kidney failure, TTP may be life-threatening. Currently, there are no treatments available, but a technique known as "plasma exchange," a process during which blood plasma is collected and exchanged, is used to normalize platelet counts and manage disease symptoms.

Baxter International Inc., through its subsidiaries, assists healthcare professionals and their patients with treatment of complex medical conditions, including haemophilia, immune disorders, cancer, infectious diseases, kidney disease, trauma and other indications.

Kaketsuken is a Juridical Foundation which researches, develops, manufactures and supplies biological products such as vaccines for humans and animals, and blood plasma derivatives, based in Kumamoto Japan.