(ChemotherapyAdvisor) – The survival benefits of adding cetuximab to chemotherapy for recurrent or metastatic squamous cell carcinoma of the head and neck are not affected by tumors’ human papillomavirus (HPV) status, according to a retrospective analysis of data from the randomized Phase 3 EXTREME trial.
The analysis of data for 381 patients was presented at the European Society for Medical Oncology (ESMO) annual meeting in Vienna, Austria.
The EXTREME (ErbituX in 1st-line Treatment of REcurrent or MEtastatic head and neck cancer) trial demonstrated an overall survival (OS) benefit when cetuximab was added to standard cisplatin or carboplatin plus 5-FU chemotherapy (median OS: 10.1 months for cetuximab+chemotherapy vs 7.4 months for chemotherapy alone; P=0.04).
The new analysis shows survival benefits associated with cetuximab were not affected by tumor HPV status, the authors reported.
“This analysis is very interesting as it suggests that patients with recurrent and/or metastatic head and neck cancer benefit from the addition of Erbitux (cetuximab) to a platinum-based chemotherapy backbone, independent of HPV status,” said Amanda Psyrri, MD, assistant professor of medicine at the University of Athens in Greece.
Among both HPV+ and HPV- patients, adding cetuximab to chemotherapy improved both OS and progression-free survival (PFS) over chemotherapy alone, Dr. Psyrri reported. Interaction tests between treatment outcomes and tumor HPV status showed that improved OS and PFS among patients treated with cetuximab were not associated with HPV status (P=0.482 for OS and P= 0.430 for PFS).
HPV+ status was associated with better outcomes in both the cetuximab- and the chemotherapy-only arms of the study.
“In the chemotherapy + cetuximab arm, the overall incidence of grade 3/4 adverse events was slightly higher among HPV+ than HPV- patients,” Dr. Psyrri said.
The number of HPV+ patients in the analysis was relatively low (n=41/381), Dr. Psyrri cautioned.
“HPV infection is linked to an increasing global incidence in head and neck cancer, so these encouraging results are of particular significance and warrant further investigation and validation,” Dr. Psyrri said.
The study was funded by Merck Serono, a division of Merck. Two authors of the study are employees of Merck.
ESMO Abstract (#1018O)