Phase II randomized trial of radiotherapy (RT), cetuximab (E), and pemetrexed (Pem) with or without bevacizumab (B) in locally advanced squamous cell carcinoma of the head and neck (SCCHN).

Abstract

6043 Background: We previously developed a novel regimen by the addition of Pem to RT and E (Ann Oncol 2011;22:2482). The current study evaluated PemE in the phase II setting and assessed the addition of B, an anti-VEGF monoclonal antibody, to PemE based on promising data with Pem/B (JCO 2011;29:1140) and E/B (Ann Oncol 2013;24:200) in recurrent/metastatic SCCHN. Methods: Patients (pts) with previously untreated stage III/IV SCCHN of the oropharynx, larynx or hypopharynx, performance status (PS) 0-1, no history of bleeding, and adequate laboratory parameters were randomized after stratification for PS, stage and site to: RT 2 Gy/day to 70Gy, E 250mg/m2 weekly, after a loading dose of 400 mg/m2 1 week prior starting RT, and Pem 500mg/m2 every 21 days x 3 cycles (arm A, PemE), or the same regimen plus B 15mg/kg every 21 days x 3 cycles during RT followed by B maintenance x 8 cycles (arm B, B-PemE), with antibiotic prophylaxis. The primary endpoint was progression-free survival (PFS) with a target of 64% at 2 years; planned sample size was 80. Results: 79 pts were randomized of whom 77 were eligible and analyzable (arm A/B:36/41); oropharynx 65/larynx 12; HPV+ 38/HPV- 15/HPV unknown 24; stage IV 54/stage III 23. 31 pts were enrolled in community centers. Treatment delivery of E and Pem was similar between arms: E, median number of doses 8 (range, 5-11); Pem 3 (2-3); and B 3 (1-3). 5 deaths occurred: 3 due to progression; 1 from unknown cause; 1 pt died from hemoptysis after bronchoscopy within 4 weeks of the 8th cycle of B leading to elimination of B maintenance after the 6th pt was enrolled. 9 pts (2 HPV+) progressed. With a median follow-up of 18 months, the 2-year PFS was 81% vs 87% and the 2-year overall survival (OS) was 96% vs 86% for arm A vs B. Grade 3/4 acute toxicities for arm A vs B (N=59) : dermatitis 3/1 vs 4/1; mucositis 13/2 vs 13/0; neutropenia 7/4 vs 7/3; rash 6/1 vs 8/1; fatigue 1/0 vs 3/0; weight loss 2/0 vs 5/0. Conclusions: Both regimens are feasible in academic and community practice settings with expected toxicities. Preliminary efficacy results are very promising and better than projected, however, the addition of B does not appear to improve outcomes. Clinical trial information: NCT00703976.