Bristol Myers exercises option on Obsidian's CD40L cell therapy 

People shaking hands across a desk that has computer and papers on it
Bristol Myers Squibb has committed to potential future milestones and royalty payments for Obsidian Therapeutics' CD40L-armed cell therapy. (rawpixel/Pixabay)

Bristol Myers Squibb has exercised its option to globally license Obsidian Therapeutics' CD40L-armed cell therapy. The deal gives Bristol Myers control of a drug designed to counter the antigen-negative tumor escape that restricts the efficacy of CAR-T cell therapies.

Celgene secured an option on cell therapies featuring technology to control the activity of CD40L and IL-12 in the run-up to its $74 billion acquisition by Bristol Myers. Having gained the option through the takeover, Bristol Myers has decided to opt in and claim its exclusive worldwide license on the CD40L program.

Atlas Venture-backed Obsidian is built upon technology for attaching drug-responsive domains (DRDs) to therapeutic proteins. In the absence of a certain small-molecule drug, the protein degrades. When the drug is present, it stabilizes the DRD-tagged protein. If the approach works as hoped, Obsidian will be able to adjust the timing and level of protein expression, providing a level of control beyond what is possible with today’s cell and gene therapies. 

Obsidian’s selection of CD40L as an early test case for the technology reflects the role the tumor necrosis factor superfamily member plays in the promotion of dendritic cell activation. Evidence of that role led researchers to create agonistic CD40 antibodies, only for systemic immune activation to cause dose-limiting toxicities. 

In cytoDRiVE, Obsidian has a technology with the potential to deliver the desired immune effects without triggering the adverse events associated with antibody-based approaches. The potential is underpinned by evidence the technology enables precise, titratable regulation of CD40L and can be included in CAR-T therapies.

Obsidian is still some way from validating that hypothesis in the clinic. However, the biotech has already gathered enough evidence to persuade Bristol Myers the idea is worth pursuing.

“By controlling the expression of armed payloads like CD40L, Obsidian's cell therapy candidates may have the potential to overcome tumor microenvironment resistance and unlock the power of cell therapy in solid tumors and other malignancies," Bristol Myers' executive vice president of R&D Rupert Vessey said in a statement. Vessey headed up research and early development at Celgene at the time of the original Obsidian deal.

Bristol Myers has committed to potential future milestones and royalty payments of undisclosed sizes to secure the worldwide license on the CD40L program. Any payments to Obsidian will support the advancement of its lead controllable tumor-infiltrating lymphocyte, which is currency on its way to the clinic.