Trial results for the Phase 1 study (NCT02819752) investigating pembrolizumab combined with chemoradiotherapy in squamous cell carcinoma of the head and neck were posted on ClinicalTrials.gov on 2025-12-18. The study reported 0 Participants experienced dose-limiting toxicities (DLTs) in the HPV+ve Stage IVA/IVB SCCHN group.

Background

Pembrolizumab (Keytruda) is an immunotherapy drug. This study investigated its combination with conventional cisplatin-based chemoradiotherapy for patients with squamous cell carcinoma of the head and neck. The trial aimed to establish the tolerability and acceptable levels of acute and late toxicity for this combination regimen.

Trial design

The PEmbrolizumab Combined With Chemoradiotherapy in Squamous Cell Carcinoma of the Head and Neck study (NCT02819752) was a Phase 1 trial that enrolled 3 participants. The study was designed to assess the tolerability and acute and late toxicity of combining pembrolizumab with conventional cisplatin-based chemoradiotherapy in patients with stage IV LA-SCCHN (Locally Advanced Squamous Cell Carcinoma of the Head and Neck). The primary focus included evaluating levels of mucosal and cutaneous toxicity within radiation fields, as well as toxicity outside the radiation portals.

Key results

The trial's key measurements focused on safety and preliminary efficacy indicators in the HPV+ve Stage IVA/IVB SCCHN group. For the outcome of "Number and Percentage of Patients With Dose Limiting Toxicities (DLT)", 0 Participants were reported to have experienced DLTs. Acute toxicity, as measured during treatment by CTCAE v4.0, was observed in 3 Participants.

Other outcomes, including "Percentage of Progression Free Survival at 6, 12 and 24 Months Post Treatment Start", "Percentage of Overall Survival at 6, 12 and 24 Months", and "Percentage of Patients With Clinical Benefit (CR/PR/SD) Using RECIST at 6, 12 and 24 Months", reported data for 3 Participants at 6 and 12 months, and for 1 Participant at 24 months, for each respective outcome.

What this means

The finding of 0 dose-limiting toxicities in the 3 enrolled participants suggests that the combination of pembrolizumab and chemoradiotherapy may be tolerable in patients with HPV+ve Stage IVA/IVB squamous cell carcinoma of the head and neck. While acute toxicities were observed in all 3 participants, the absence of DLTs is an important safety signal for this Phase 1 study. Given the very small enrollment, no definitive conclusions can be drawn regarding efficacy, but these safety data are crucial for informing potential future studies with larger cohorts.

Source

The information for these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT02819752, titled "PEmbrolizumab Combined With Chemoradiotherapy in Squamous Cell Carcinoma of the Head and Neck," were posted on 2025-12-18 on clinicaltrials.gov.