Bristol Myers ends blood cancer drug partnership with Cellares

Bristol Myers Squibb has terminated its 2024 manufacturing partnership with cell therapy startup Cellares, worth up to $380 million, after determining that Cellares' Cell Shuttle platform could not produce the CAR-T blood cancer therapy Breyanzi at commercial scale. Following the loss of this major customer, Cellares announced plans to lay off 100 employees by October 20, 2026, despite recently raising $327 million in a Series D funding round.

Bristol Myers partnership termination

• ▪Bristol Myers Squibb and Cellares signed a deal in 2024 worth up to $380 million under which Bristol Myers Squibb reserved manufacturing capacity across the United States, the European Union, and Japan.
• ▪Bristol Myers Squibb ended its partnership with cell therapy startup Cellares to expand the manufacturing of its personalized blood cancer therapy Breyanzi, as reported on August 25, 2026.

Cell Shuttle platform limitations

• ▪Bristol Myers Squibb determined that Cellares' automated cell therapy manufacturing platform, Cell Shuttle, could not meet the requirements to make its CAR-T therapy, Breyanzi, at commercial scale.
• ▪Cellares bills its automated Cell Shuttle manufacturing pods as technology that can help speed up the production of cell therapies.

Cellares workforce reduction

• ▪Cellares closed a $327 million Series D funding round in June 2026, approximately two months before announcing its workforce reduction.
• ▪Cellares CEO Fabian Gerlinghaus announced the workforce reduction on LinkedIn, stating it was triggered by the termination of a contract by an unnamed large pharmaceutical customer.
• ▪Cellares plans to lay off 100 employees, primarily software engineers, quality control and design staff, and manufacturing specialists, by October 20, 2026.

CAR-T manufacturing challenges

• ▪Germany-based cell therapy manufacturer Evotec announced in March 2026 that it would lay off 800 employees in its second round of layoffs since 2024.
• ▪CAR-T therapies require removing a patient's immune cells, reprogramming them in a lab to fight cancer, and infusing them back into the body, making them difficult and expensive to produce.

Breyanzi commercial production requirements

• ▪Breyanzi, a CAR-T therapy first approved by the U.S. Food and Drug Administration in 2021 to treat lymphoma and other blood cancers, generated $1.36 billion in sales in 2025.
• ▪Bristol Myers Squibb's decision to terminate its partnership with Cellares applies only to Breyanzi and its approved manufacturing process.

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