Philochem AG, a wholly-owned subsidiary of the Philogen Group, and RayzeBio Inc., a wholly-owned subsidiary of Bristol-Myers Squibb, have inked a definitive agreement under which Philochem will license the exclusive worldwide rights to develop, manufacture, and commercialize OncoACP3, a clinical stage therapeutic and diagnostic agent targeting prostate cancer, to RayzeBio.

OncoACP3, a small molecule ligand with exceptional affinity and specificity for Acid Phosphatase 3 (ACP3), a novel target in prostate cancer, is currently undergoing evaluation in a company-sponsored Phase I trial (NCT06840535). The initial data from the first cohort of patients treated with the OncoACP3 diagnostic has shown promising results, demonstrating selective tumor uptake and a prolonged residence time with minimal uptake of healthy tissue. IND-enabling activities are ongoing to support the application for a Phase I therapeutic study with 225Ac-OncoACP3.

Prof. Dr. Dario Neri, CEO and CSO of Philogen, said, “We are delighted to enter into this new collaboration with RayzeBio, a leader in the field of radiopharmaceutical medicines. This partnership will focus on the development and commercialization of OncoACP3 for both diagnostic and therapeutic applications in prostate cancer.”

Ben Hickey, President, RayzeBio commented, “This collaboration with Philochem enhances our leadership in the rapidly advancing radiopharmaceuticals space, consistent with our strategy to bring forward best-in-class RPT candidates. OncoACP3, with its initial encouraging safety profile, provides a differentiated entry for Bristol Myers Squibb and RayzeBio into the prostate cancer arena, building on our leadership in actinium-based RPT development. This agreement is a significant milestone for RayzeBio and our goal to deliver radiopharmaceuticals to patients.”

Under the terms of the agreement, Philochem will receive an up-front payment of $350m and up to $1.0bn in development, regulatory and commercial milestones. The company will also receive midsingle to low double-digit royalties payable on Global Net Sales of both Therapeutic and Diagnostic agents of OncoACP3.

The closing of the transaction is subject to regulatory approvals and other customary closing conditions. The parties expect that the agreement will close in the third quarter of 2025.