Petosemtamab granted Breakthrough Therapy designation by the U.S. FDA for 1L PD-L1 positive head and neck squamous cell carcinoma

Core Insights - The U.S. FDA has granted Breakthrough Therapy designation (BTD) to petosemtamab in combination with pembrolizumab for first-line treatment of adult patients with recurrent or metastatic PD-L1 positive head and neck squamous cell carcinoma (HNSCC) with CPS ≥ 1 [1][4] - This is the second BTD designation for petosemtamab, following the initial BTD and Fast Track designations for patients whose disease progressed after platinum-based chemotherapy and anti-PD-1 therapy [2] Clinical Data and Trials - The BTD is supported by updated data from an ongoing phase 1/2 trial showing a 67% response rate among 24 evaluable patients with PD-L1 positive r/m HNSCC [3] - Merus plans to conduct two phase 3 trials: LiGeR-HN1 will evaluate petosemtamab with pembrolizumab versus pembrolizumab alone, while LiGeR-HN2 will compare petosemtamab to standard therapies in patients who have progressed after anti-PD-1 and platinum therapies [5][6] Company Commitment and Future Plans - The company believes that the second BTD validates petosemtamab's potential to become a new standard of care for r/m HNSCC and emphasizes its commitment to accelerate development [4] - With the BTD, Merus aims to engage in expedited discussions with the FDA towards a potential Biologics License Application (BLA) submission [4] Background on HNSCC - HNSCC is a significant global health issue, with over 930,000 new cases and 465,000 deaths reported in 2020, and the incidence is expected to rise by 30% by 2030 [7][8] - The disease is associated with risk factors such as tobacco use, alcohol consumption, and HPV infections [7] About Petosemtamab - Petosemtamab is a Biclonics low-fucose human IgG1 antibody targeting EGFR and LGR5, designed to inhibit EGFR signaling and enhance immune-mediated cytotoxicity [9] About Merus N.V. - Merus is a clinical-stage oncology company focused on developing innovative bispecific and trispecific antibody therapeutics, known as Multiclonics, which have shown promising features in preclinical and clinical studies [10]