Merus updates on Petosemtamab+Pembrolizumab data in HNSCC

Merus (MRUS) N.V. “announced interim clinical data as of a February 27, 2025 data cutoff from the ongoing phase 2 trial of the bispecific antibody petosemtamab in combination with pembrolizumab. These data will be presented by Dr. Carla M. L. van Herpen M.D. Ph.D., Radboud University Medical Center, Nijmegen, Netherlands at the 2025 American Society of Clinical Oncology(R) Annual Meeting on Monday, June 2 at 9 a.m. – 12:00 p.m. CT.” “By essentially every metric, we believe these interim data are significantly better than pembrolizumab monotherapy, the control arm of our ongoing phase 3 trial, and underscores the opportunity petosemtamab holds to become a new standard of care, if approved, in head and neck cancer,” said Bill Lundberg, CEO. “Additionally, we believe our execution is outstanding with rapid site initiation. We are looking forward to potentially sharing top line interim readout of one or both of our phase 3 trials in 2026. Head and neck squamous cell carcinoma is associated with a poor prognosis and high mortality rate, and there remains a need for new treatment options for patients. In my clinic, I have witnessed firsthand profound tumor shrinkage with petosemtamab administration, and the efficacy results petosemtamab has shown thus far in combination with the current standard of care, pembrolizumab. I’m excited by the impressive ORR and durability of those responses, and what these results, if replicated more broadly could mean for the future of our practice in head and neck cancer.”