Monte Rosa Therapeutics (NASDAQ:GLUE) reported encouraging early clinical results for its molecular glue degrader MRT-2359 in combination with enzalutamide, showing pronounced activity in a genetically defined subset of heavily pretreated metastatic castration-resistant prostate cancer (mCRPC).
Updated data from the ongoing study, covering 20 enrolled patients as of Dec. 3, underscore a striking response pattern among those harboring androgen receptor (AR) mutations.
Of the 14 patients evaluable by RECIST criteria, four had AR-mutant disease—a subgroup that posted a 100% prostate-specific antigen (PSA) response rate, including two PSA90 responses.
All four also achieved disease control, with two confirmed RECIST responses, highlighting the potential for MRT-2359 to address resistance mechanisms common in advanced prostate cancer.
Across the broader RECIST-evaluable population, disease control reached 64% (9 of 14 patients).
Meanwhile, safety remained manageable, dominated by Grade 1–2 gastrointestinal events consistent with earlier clinical experience for MRT-2359.
Monte Rosa said the emerging signals support advancing the combination into a signal-confirming Phase 2 study, expected to enroll up to 25 patients beginning in 2026.
The company plans to present additional data at the ASCO Genitourinary Cancers Symposium in February 2026, where analysts expect greater clarity on the durability and biomarker correlations of treatment response.