Fixed-dose pembrolizumab induced durable responses and was well tolerated among patients with recurrent and/or metastatic head and neck squamous cell carcinoma (HNSCC), according to a study published in the Journal of Clinical Oncology.1
The KEYNOTE-012 study (ClinicalTrials.gov Identifier: NCT01848834) demonstrated that treatment with pembrolizumab, an anti-programmed death-1 antibody, resulted in durable antitumor activity in programmed death-ligand 1 (PD-L1)-positive advanced HNSCC. This trial led to the accelerated approval of pembrolizumab for this indication, regardless of PD-L1 expression status.
In an expansion cohort of the KEYNOTE-012 study, researchers evaluated the activity and safety of pembrolizumab among patients with recurrent or metastatic HNSCC, irrespective of PD-L1 or human papillomavirus (HPV) status.
Among the 132 evaluable patients, the overall response rate was 18% (95% CI, 12-26) by independent review, which included 4 complete and 20 partial responses, and 20% (95% CI, 13-28) per investigator assessment.
Median duration of response was not reached, but some responses have lasted longer than 11 months.
Six-month progression-free survival was 23%; 6-month overall survival was 59%.
Overall response rate was 22% among patients with PD-L1-positive tumors, in contrast with 4% among PD-L1-negative patients. Overall response rate was 32% and 14% among patients with HPV-associated and non-HPV-associated HNSCC, respectively.
Sixty-two percent of patients had any grade treatment-related adverse events; 9% reported grade 3 or worse treatment-related adverse events. The most common adverse reactions included fatigue, hypothyroidism, and decreased appetite.
The findings support further evaluation of fixed-dose pembrolizumab for patients with recurrent and/or metastatic HNSCC.
- Chow LQM, Haddad R, Gupta S, et al. Antitumor activity of pembrolizumab in biomarker-unselected patients with recurrent and/or metastatic head and neck squamous cell carcinoma: Results from the phase Ib KEYNOTE-012 expansion cohort. J Clin Oncol. 2016 Sep 19. doi: 10.1200/JCO.2016.68.1478 [Epub ahead of print]