Merus to Showcase Interim Findings on Petosemtamab at AACR-NCI-EORTC Conference

Clinical Trial Overview: Merus presented interim clinical data from a phase 2 trial of petosemtamab, a bispecific antibody, in combination with FOLFOX/FOLFIRI for metastatic colorectal cancer (mCRC) and as monotherapy for later lines of treatment.

Efficacy Results: In the 1L treatment group, there was an 80% response rate with 1 complete response and 7 partial responses; in the 2L group, a 62% response rate was observed; the 3L+ monotherapy group showed a 10% confirmed response rate.

Patient Demographics: The trial included 54 patients with KRAS, NRAS, and BRAF wildtype microsatellite stable mCRC, with varying prior treatment histories, including no prior anti-EGFR therapy for 1L and 2L patients.

Safety Profile: The safety profile of petosemtamab was consistent with previous studies, showing no new safety signals or significant overlapping toxicities when combined with FOLFOX/FOLFIRI, and infusion-related reactions were manageable.