Oric to Launch Phase 3 Rinzimetostat Trial with J&J Apalutamide in H1 2026
Oric Pharmaceuticals completed dose exploration for its allosteric PRC2 inhibitor rinzimetostat combined with Johnson & Johnson’s apalutamide and plans to launch a Phase 3 metastatic castration-resistant prostate cancer study in the first half of 2026. Early data show a 20–24 hour half-life and favorable safety profile versus competing PRC2 inhibitors.
1. Phase 3 Trial Plans
Oric has finished dose exploration for rinzimetostat plus apalutamide and darolutamide combinations and intends to initiate its first Phase 3 study in metastatic castration-resistant prostate cancer in the first half of 2026. The trial will feature dose optimization data from 20–25 patients, assessing PSA50/PSA90 response rates, safety, circulating tumor DNA, and an early durability landmark analysis at three to four months.
2. Differentiation and Clinical Profile
Rinzimetostat’s 20–24 hour half-life contrasts with competitors’ shorter profiles, supported by its allosteric EED-binding mechanism that inhibits both EZH2 and EZH1. Early pharmacokinetic and safety data indicate lower gastrointestinal and hematologic toxicity rates, positioning the combination for potentially improved tolerability and efficacy in combination regimens.
3. Implications for Apalutamide
The collaboration with Johnson & Johnson to combine apalutamide with rinzimetostat could broaden apalutamide’s therapeutic reach beyond monotherapy, potentially boosting its market share in metastatic castration-resistant prostate cancer if the Phase 3 trial confirms differentiated efficacy and safety benefits.