Final Results of a Randomized Phase 2 Trial Investigating the Addition of Cetuximab to Induction Chemotherapy and Accelerated or Hyperfractionated Chemoradiation for Locoregionally Advanced Head and Neck Cancer.

Purpose: The role of cetuximab in the treatment of locoregionally advanced head and neck squamous cell cancer (LA-HNSCC) remains poorly defined. In this phase 2 randomized study, we investigated the addition of cetuximab to both induction chemotherapy (IC) and hyperfractionated or accelerated chemoradiation.
Methods and Materials: Patients with LA-HNSCC were randomized to receive 2 cycles of weekly IC (cetuximab, paclitaxel, carboplatin) and either Cetux-FHX (concurrent cetuximab, 5-fluorouracil, hydroxyurea, and 1.5 Gy twice-daily radiation therapy every other week to 75 Gy) or Cetux-PX (cetuximab, cisplatin, and accelerated radiation therapy with delayed concomitant boost to 72 Gy in 42 fractions). The primary endpoint was progression-free survival (PFS), with superiority compared with historical control achieved if either arm had 2-year PFS ≥70%.
Results: 110 patients were randomly assigned to either Cetux-FHX (n=57) or Cetux-PX (n=53). The overall response rate to IC was 91%. Severe toxicity on IC was limited to rash (23% grade ≥3) and myelosuppression (38% grade ≥3 neutropenia). The 2-year rates of PFS for both Cetux-FHX (82.5%) and Cetux-PX (84.9%) were significantly higher than for historical control (P<.001). The 2-year overall survival (OS) was 91.2% for Cetux-FHX and 94.3% for Cetux-PX. With a median follow-up time of 72 months, there were no significant differences in PFS (P=.35) or OS (P=.15) between the treatment arms. The late outcomes for the entire cohort included 5-year PFS, OS, locoregional failure, and distant metastasis rates of 74.1%, 80.3%, 15.7%, and 7.4%, respectively. The 5-year PFS and OS were 84.4% and 91.3%, respectively, among human papillomavirus (HPV)-positive patients and 65.9% and 72.5%, respectively, among HPV-negative patients.
Conclusions: The addition of cetuximab to IC and chemoradiation was tolerable and produced long-term control of LA-HNSCC, particularly among poor-prognosis HPV-negative patients. Further investigation of cetuximab may be warranted in the neoadjuvant setting and with non-platinum-based chemoradiation.
(Copyright © 2016. Published by Elsevier Inc.)