Prelude Therapeutics has announced a clinical collaboration with Merck to evaluate the combination of Prelude's PRT3789, a selective SMARCA2 degrader, with Merck's anti-PD-1 therapy, KEYTRUDA, in patients with SMARCA4-mutated cancers. The Phase 2 clinical study aims to explore the potential of this combination to enhance anti-tumor activity due to the complementary mechanisms of the two treatments. Prelude will sponsor the trial, while Merck will supply KEYTRUDA. PRT3789 is in Phase 1 development for SMARCA4 mutant patients, with dose escalation expected to conclude mid-2024. Early pre-clinical data indicated promising anti-tumor immunity and tumor regression when combining SMARCA2 degraders with anti-PD-1 therapies. Both companies retain commercial rights to their respective treatments.