Onyx To Acquire Proteolix

Onyx Pharmaceuticals has signed an agreement to acquire Proteolix, Inc., a privately held biopharmaceutical company focused on discovering and developing novel therapies that target the proteasome for the treatment of hematological malignancies and solid tumors. Proteolix’s lead compound, carfilzomib, is a proteasome inhibitor currently in multiple clinical trials, including a Phase IIb trial for patients with relapsed and refractory multiple myeloma.

“Carfilzomib is a next-generation product candidate with a proven and well-validated mechanism of action, strong efficacy signals, demonstrated tolerability and a potential accelerated approval pathway,” said N. Anthony Coles, M.D., president and chief executive officer of Onyx. “This acquisition leverages Onyx’s proven expertise in developing and commercializing Nexavar and provides strategic expansion into the $16 billion hematological malignancies market. The transaction structure reflects our approach to growing our business in a disciplined fashion, including earnout payments contingent on specific approval-based events. In addition, our development plan is designed to maintain our ability to continue to grow operating cash flow in 2010 and beyond.”

Onyx will make a $276 million cash payment upon closing of the transaction. Additional payments include $40 million payable in 2010 based on the achievement of a development milestone and as much as $535 million contingent upon the achievement of certain regulatory approvals for carfilzomib in the U.S. and Europe. A payment of $170 million (of the potential $535 million) is based upon the achievement of accelerated FDA approval. The transaction is expected to close in 4Q09, subject to the receipt of clearance under the Hart-Scott-Rodino Act and customary closing conditions.