Onyx Pharmaceuticals to Acquire Proteolix
US-based Onyx Pharmaceuticals has signed a definitive agreement to acquire Proteolix, a biopharmaceutical company focused on discovering and developing novel therapies that target the proteasome for the treatment of hematological malignancies and solid tumors.
US-based Onyx Pharmaceuticals has signed a definitive agreement to acquire Proteolix, a biopharmaceutical company focused on discovering and developing novel therapies that target the proteasome for the treatment of hematological malignancies and solid tumors.
Under the terms of the transaction, Onyx will make a US$276m (Euro 185m) cash payment upon closing of the transaction. Additional payments include $40m (€27m) payable in 2010 based on the achievement of a development milestone and up to $535m (€359m) contingent upon the achievement of certain regulatory approvals for Proteolix's lead compound, carfilzomib, in the US and Europe.
Of the potential $535m, a payment of $170m (€114m) is based upon the achievement of accelerated US FDA approval. The transaction is expected to close in the fourth quarter of 2009, subject to the necessary clearance and customary closing conditions.
Proteolix is developing several therapeutics that inhibit the cellular proteasome. Carfilzomib is a next generation proteasome inhibitor, selectively targeting the threonine protease with prolonged target suppression and improved antitumour activity in proof of concept trials. An ongoing 250-patient Phase 2b trial in patients with relapsed and refractory multiple myeloma is expected to complete enrolment in 2009 with data expected in the second half of 2010 to support a potential new drug application (NDA) filing by year-end 2010.
A Phase 3 trial evaluating the combination of carfilzomib in combination with Revlimid and dexamethasone as a potential treatment option for patients with relapsed and refractory multiple myeloma is expected to begin in 2010. In addition, carfilzomib is being evaluated in a Phase 2 trial in relapsed patients with multiple myeloma. Carfilzomib is also being evaluated in a Phase 1b/2 study for solid tumor cancers.
Proteolix is developing two molecules in addition to carfilzomib: an oral proteasome inhibitor and a selective inhibitor of the immunoproteasome.
"There is a tremendous need for new agents in multiple myeloma that can extend and improve the lives of patients and be used in combination with existing therapies," said Todd Yancey, vice president clinical development at Onyx. "Current therapies are limited by serious side effects, particularly neurotoxicity, as well as limited duration of response and resistance."