Relay teams with with Pfizer for RLY-2608/atirmociclib combo evaluation for BC

Relay Therapeutics (RLAY) announced a clinical trial collaboration with Pfizer (PFE) to evaluate atirmociclib, Pfizer’s investigative selective-CDK4 inhibitor, in combination with RLY-2608 and fulvestrant in patients with PI3Kalpha-mutated, HR+, HER2- metastatic breast cancer. “We are very enthusiastic to evaluate Pfizer’s novel investigative selective-CDK4 inhibitor atirmociclib in combination with RLY-2608, the first mutant selective PI3Kalpha inhibitor,” said Don Bergstrom, M.D., Ph.D., President of R&D at Relay Therapeutics. “We believe that combining these two selective agents – atirmociclib and RLY-2608 – will avoid key off-target toxicity that comes from hitting CDK6 and wild-type PI3Kalpha, which has historically significantly limited use of non-selective agents. The breast cancer treatment landscape continues to evolve quickly, and we are pleased that the safety profile RLY-2608 has demonstrated to-date makes it well-positioned to be part of the next generation of therapies.” Under the terms of the agreement, Pfizer will provide atirmociclib for use in the study and Relay will be responsible for conducting the study. The RLY-2608 + atirmociclib + fulvestrant triplet combination is planned to begin by the end of 2024.