Merus Updated ASCO data confirm best-in-class potential in 1L HNSCC

Merus reported solid interim Ph2 data for ASCO 2025 with peto combo with Keytruda in 1L PD-L1+ r/m HNSCC, tracking nicely in line with last year's ASCO data. The updated dataset featured a 63% ORR (incl. 6 CRs), a mPFS of 9 months, and 12-month survival rate of 79%. Responses were observed across PD-L1 levels and HPV+ subgroups, and the treatment showed no new safety signals. The data support petosemtamab's potential to outperform Keytruda monotherapy and become the new gold standard in head and neck cancer. Ongoing Ph3 trials are progressing with interim topline data in one or both trials by 2026. We reiterate our $ 59 TP and Buy rating.