Cetuximab with or without sorafenib in recurrent/metastatic (R/M) squamous cell carcinoma of the head and neck (SCCHN).

Abstract

Listen

Translate article

6047 Background: For patients with R/M SCCHN, cetuximab, a monoclonal antibody against EGFR, is approved as a single agent and has a survival benefit when combined with chemotherapy. We hypothesized that addition of sorafenib, a multi-kinase inhibitor of targets including VEGFR, to cetuximab may have greater clinical benefit than cetuximab alone. Methods: This trial was designed as a blinded, randomized phase II, placebo-controlled study of cetuximab at 400 mg/m2 IV on day 1 followed by 250 mg/m2 IV weekly plus placebo bid (Arm A) or cetuximab at the same dose and schedule plus sorafenib 400 mg po bid (Arm B), each in 21 day cycles. After 19 patients were enrolled, the trial was amended to remove the placebo (and blinding) due to issues with placebo tablet solubility. Target sample size was 84 patients with 83% power to detect a 2-month increase in PFS, the primary study endpoint. Interim analysis was planned at midpoint, requiring hazard ratio < 1 to proceed to the second stage of study. Serum cytokine and tumor HPV ISH and p16 analyses were performed. Results: Of 56 patients (ages 26-74, 80% male) enrolled, 53 patients received treatment and 41 were evaluable for response. Of the patients who received therapy, 26 received cetuximab only (Arm A). For Arm A, the mean number of cycles delivered was 4.3 (range 1-16) and the mean for Arm B was 3.3 (range 1-11). The most common grade 3/4 AEs were fatigue (2 A, 1 B), hypertension (3 B), infusion reaction (both arms), and diarrhea (2 B). Arm A had 2 PRs and Arm B had 4 PRs. Median OS was 7 mo and 5.9 mo respectively. Median PFS was 3.1 mo for both arms. 24 patients had pre-treatment cytokine measurements. Of the 12 measured cytokines, high TGFB1 level was significantly correlated with inferior PFS (4.6 mo vs 1.6 mo), regardless of arm (p=0.015). 38 patients had tumors available for p16 staining (31 neg and 7 pos). 3 of 7 p16 pos were also HPV ISH pos. The p16 neg patients had significantly improved PFS (3.5 mo vs 1.6 mo) regardless of arm (p=0.032) but no difference in OS (p=1.0). Conclusions: Both arms demonstrated clinical activity although no significant difference was observed. However, a subset of patients with p16 neg tumors or low serum TGFB1 may have a greater benefit with cetuximab-based therapy. Clinical trial information: NCI-2012-02847.