BMS Expands Radiopharmaceutical Portfolio with $1.35B Philochem Deal, Targeting Novel Prostate Cancer Biomarker

Bristol Myers Squibb (BMS) has made a significant move in the radiopharmaceutical space, announcing a $1.35 billion biobucks deal with Italian-Swiss biotech Philochem. The collaboration aims to advance an early-stage small-molecule radiotherapeutic targeting a novel biomarker in prostate cancer, potentially offering a new approach to treatment in an increasingly competitive field.

Deal Structure and Financial Details

BMS, through its radiopharmaceutical subsidiary RayzeBio, has committed an upfront payment of $350 million to Philochem. The agreement includes potential additional payments of up to $1 billion in development, regulatory, and commercial milestones. Furthermore, Philochem stands to receive mid-single to low-double-digit royalties on global net sales of any resulting products. The transaction is expected to close in the third quarter of this year, subject to customary approvals.

Focus on Novel Prostate Cancer Target

The centerpiece of the collaboration is OncoACP3, a small-molecule radiotracer developed by Philochem. Unlike many competitors focusing on the well-established PSMA (Prostate-Specific Membrane Antigen) target, OncoACP3 binds to a novel marker called ACP3. According to Philochem, ACP3 is highly expressed in prostate cancer tissues but not in healthy tissues, potentially offering improved specificity.

Notably, Philochem claims that ACP3 expression levels in prostate cancer match or exceed those of PSMA. The company's website states, "A side-by-side comparison between ACP3 and PSMA has shown that ACP3 is more abundantly expressed in prostate cancer than PSMA." This characteristic could provide a significant advantage in terms of targeting efficiency and therapeutic efficacy.

Technical Advantages and Versatility

OncoACP3 demonstrates high affinity for the ACP3 protein and possesses the ability to carry both Lutetium-177 and Actinium-225, which are currently the most common payloads for radiopharmaceuticals. This versatility may allow for the development of multiple therapeutic approaches using a single targeting molecule.

RayzeBio president Ben Hickey emphasized the strategic importance of this deal, stating that by potentially opening an alternative pathway to PSMA, the Philochem partnership "provides a differentiated entry" for BMS "into the prostate cancer arena."