Genmab reports 28.2-month survival in head and neck cancer trial

• Genmab reported updated Phase 2 results showing median overall survival of 28.2 months with petosemtamab plus pembrolizumab in patients with previously untreated, recurrent or metastatic PD-L1-positive head and neck cancer.
• The combination achieved a 63% objective response rate, including 19% complete responses, and median progression-free survival of 9.0 months among 43 efficacy-evaluable patients.
• Genmab is advancing petosemtamab through its Phase 3 LiGeR clinical program, with topline results anticipated later in 2026 as the company evaluates its potential in head and neck cancer.

Genmab A/S (NASDAQ:GMAB) reported updated Phase 2 results showing median overall survival of 28.2 months for petosemtamab combined with pembrolizumab in first-line treatment of recurrent or metastatic PD-L1-positive head and neck squamous cell carcinoma.

Among 43 efficacy-evaluable patients, the investigational combination achieved a 63% objective response rate, including a 19% complete response rate, and median progression-free survival of 9.0 months.

“The median overall survival of 28 months observed with petosemtamab plus pembrolizumab in this trial, along with a manageable safety profile, are impressive,” said study investigator Amaury Daste of the University Hospital of Bordeaux in France.

At the May 15, 2026 data cutoff, median follow-up reached 25.5 months, with a 79% overall survival rate at 12 months and an estimated 55% of responders maintaining their response at 24 months.

Genmab expects topline results from its ongoing Phase 3 head and neck cancer program later in 2026, including the LiGeR-HN1 trial evaluating petosemtamab in first-line PD-L1-positive disease.

The most common treatment-emergent adverse events were asthenia and acneiform dermatitis, each occurring in 51% of patients, and rash in 49%, while infusion-related reactions occurred in 38% and no Grade 5 events or treatment-related deaths were reported.

Petosemtamab is an investigational bispecific antibody targeting EGFR and LGR5, with responses observed across HPV-positive and HPV-negative disease, although the nonrandomized Phase 2 findings do not establish a survival advantage over existing treatments.