Baxter International, a global, diversified healthcare company, has agreed to acquire all of Chatham Therapeutics’ outstanding membership interests. Chatham is a privately held clinical development-stage biotechnology company. As a result, Baxter will acquire Chatham’s developmental gene therapy programs directed toward the development and commercialization of treatments for hemophilia.

In May 2012, Baxter and Chatham entered into a collaboration to evaluate Chatham’s Biological Nano Particle (BNP) platform—an advanced recombinant adeno-associated virus (rAAV)-based gene therapy technology—as a potential treatment for hemophilia B, known as BAX 335, which currently is in a phase I/II study aiming to enroll 16 subjects. Baxter will obtain broad access to Chatham’s gene therapy platform, including the previously partnered hemophilia B (FIX) program, a preclinical hemophilia A (FVIII) program and the potential future application to additional hemophilia treatments.

''Chatham’s gene therapy platform technology offers the potential to redefine treatment of both hemophilia A and B,'' said Ludwig Hantson, Ph.D., president of Baxter BioScience. ''This technology will be highly complementary to our expanding pipeline of bleeding disorder treatments as we continue our pursuit of a bleed-free world.''

Baxter will make an initial payment of $70 million to acquire all of the outstanding membership interests of Chatham. Baxter may make additional payments in the future based on specified development, regulatory and commercial milestones.

Baxter will continue the ongoing phase I/II open-label clinical trial to assess the safety and optimal dosing schedule of BAX 335, an investigational FIX gene therapy treatment for hemophilia B. The BNP technology provides a mechanism for the patient's own liver to begin producing FIX following a single dose of the genetically engineered treatment. The design of the vector allows for more targeted delivery of the FIX therapeutic “cargo” into the natural site of FIX synthesis. This may permit effective therapy with low quantities of the vector.

Chatham will maintain its licensing and development relationship with Asklepios BioPharmaceutical (AskBio) on the development of novel hemophilia therapeutic gene therapy candidates using the BNP platform. AskBio is involved with the development of its proprietary BNP gene-delivery platform technology for therapeutics targeting diseases in the heart, CNS, muscle, ocular and liver tissues.