Werner helicase inhibitor for advanced microsatellite instability solid tumors: a phase 1 trial.

RO7589831, a WRN inhibitor, shows manageable safety and a 74.2% disease control rate in MSI solid tumors at doses of 150 mg and 600 mg BID.

• Why it matters: Targeting WRN in MSI cancers addresses a critical need for effective therapies in tumors with limited options, as these cancers often resist standard treatments.
• What they did: The phase 1 trial evaluated escalating doses of RO7589831 in 88 patients with MSI or mismatch repair-deficient tumors, assessing safety, tolerability, and preliminary efficacy through clinical and molecular measures.
• The result: Findings indicate a tolerable safety profile, with some partial responses and durable disease control, supporting further studies to confirm its therapeutic potential in MSI cancers.