secwatch.observer — SEC 8-K summary
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Issuer:     Monte Rosa Therapeutics, Inc. (GLUE)
CIK:        0001826457
Form:       8-K
Filed at:   2025-12-16T23:59:59+00:00
Accession:  0001193125-25-319981
Event type: other_material
Sentiment:  positive
Materiality: 0.75
Item codes: 7.01, 8.01, 9.01
LLM model:  deepseek-v4-flash:cloud@v2

MRT-2359 + enzalutamide shows 100% PSA response in AR-mutant mCRPC; Phase 2 planned 2026
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- In 14 evaluable mCRPC patients, overall DCR 64% (9/14); in AR-mutant subset (n=4), 100% PSA response rate and 100% DCR, with 2 RECIST partial responses.
- Combination well tolerated with primarily Grade 1-2 GI adverse events; no new safety signals.
- Company plans to initiate Phase 2 study of MRT-2359 + AR inhibitor targeting AR-mutant mCRPC patients in 2026.
- Breast cancer cohort (n=6) discontinued due to insufficient activity; MRT-8102 interim Phase 1 data expected early 2026.
- Updated MRT-2359 data to be presented at ASCO GU Symposium in February 2026.

Source:
  EDGAR index:    https://www.sec.gov/Archives/edgar/data/1826457/000119312525319981/0001193125-25-319981-index.htm
  Primary doc:    https://www.sec.gov/Archives/edgar/data/1826457/000119312525319981/glue-20251216.htm
  HTML page:      https://secwatch.observer/filing/0001193125-25-319981

License: Source filings: public domain (SEC EDGAR). Summaries (headline + bullets): CC-BY-4.0; attribute https://secwatch.observer