Cetuximab + platinum-based therapy (PBT) as a first-line treatment for patients with recurrent and/or metastatic squamous cell carcinoma of the head and neck (R/M SCCHN): An observational study (ENCORE)

Abstract

Background: The EXTREME regimen (cetuximab + PBT ≤ 6 cycles followed by cetuximab-alone maintenance until progressive disease [PD]) was the first treatment in 30 years to significantly improve disease control and overall survival (OS) vs PBT in patients (pts) with first-line (1L) R/M SCCHN (median progression-free survival [PFS], 5.6 vs 3.3 months; median OS, 10.1 vs 7.4 months). ENCORE is a multinational, observational, prospective, open-label study investigating the real-world treatment practices, efficacy, and safety of the EXTREME regimen in 1L R/M SCCHN. The primary objective was to characterize the ways the 1L R/M treatment regimen is administered in SCCHN. Methods: This study (EMR 062202-566) enrolled 225 pts with previously untreated R/M SCCHN from Italy, France, Portugal, Russia, Algeria, and South Africa, who were planned to receive 1L treatment with cetuximab + PBT. Results: 221 pts were evaluable. Median age was 64 years, 76% were male, and 85% had an ECOG performance status of 0 or 1. 51% of patients had recurrent disease, 9% had recurrent and metastatic disease, and 40% had metastasis at first presentation. 40% of patients received cisplatin, and 59% received carboplatin. Only 54% of patients received 5-fluorouracil (5-FU). 14% had previously received cetuximab as part of their concomitant treatment, and 12% had PD < 6 months since the last platinum dose in the locally advanced setting. 206 pts (93%) were planned to receive cetuximab maintenance until PD, and 97 of the 202 pts with known stop date (48%) received cetuximab maintenance. Median PFS was 6.5 months (95% CI, 5.4–7.6), and median OS was 10.2 months (95% CI, 8.5–12.6). Serious adverse events occurred in 36% of pts, with 5% related to cetuximab. Conclusions: The ENCORE trial showed, in an international real-world setting, OS and PFS with 1L cetuximab + PBT that were comparable to what was observed in the randomized, phase 3 EXTREME study. Notably, the EXTREME regimen was feasible in an unselected population and was adapted in a substantial proportion of patients, with almost half of them not receiving 5-FU. Final data will be presented at the congress. Clinical trial identification: Trial Protocol Number: EMR 062202-566. Editorial acknowledgement: Medical writing support was provided by ClinicalThinking, and was funded by Merck KGaA, Darmstadt, Germany. Legal entity responsible for the study: Merck KGaA. Funding: Merck KGaA. Disclosure: C. Le Tourneau: Honoraria: MSD, Bristol-Myers Squibb, Roche, Amgen, Novartis, Merck Serono, Nanobiotix. All other authors have declared no conflicts of interest.