Bristol Myers Squibb is further expanding its radiopharmaceutical capabilities through a strategic partnership between its subsidiary RayzeBio and Swiss biotech firm Philochem AG. As announced on June 10, 2025, the agreement grants RayzeBio exclusive worldwide rights to Philochem’s clinical-stage radiopharmaceutical candidate OncoACP3. This molecule targets Acid Phosphatase 3 (ACP3), a biomarker prevalent in prostate cancer, and is designed for both diagnostic imaging and therapeutic applications.
Under the terms of the deal, RayzeBio will pay Philochem 350 million USD upfront, with the potential for additional milestone payments totaling up to 1 billion USD, alongside mid-single to low-double-digit royalties on global net sales. OncoACP3 is currently undergoing a Phase I clinical trial as a PET imaging agent and has demonstrated promising tumor selectivity, prolonged retention, and low background uptake. IND-enabling studies are also underway for therapeutic candidates labeled with actinium‑225 and lutetium‑177.
RayzeBio President Ben Hickey described the acquisition as a step forward in strengthening the company’s leadership in targeted radiopharmaceuticals, especially for treating prostate cancer. Philochem CEO Professor Dario Neri hailed OncoACP3 as a best-in-class agent with significant therapeutic potential.
This collaboration follows Bristol Myers Squibb’s USD 4.1 billion acquisition of RayzeBio in 2023 and aligns with the company's broader ambition to lead in the rapidly growing radiopharma sector, which is projected to exceed USD 26.5 billion by 2031. The transaction is expected to close by Q3 2025, pending customary regulatory approvals.
