Phase 1 study of cetuximab in combination with 5-fluorouracil, cisplatin, and radiotherapy in patients with locally advanced anal canal carcinoma.

Background: This study sought to determine the feasibility and recommended phase 2 dose (RP2D) of the combination of cetuximab with chemoradiotherapy based on 5-fluorouracil (5-FU) and cisplatin (CP) in locally advanced anal canal carcinoma.

Methods: Cetuximab was administered on days 1, 8, 15, 29, 36, 43, and 50 (400 mg/m(2) initial dose, then 250 mg/m(2) /week) concurrent with total dose radiation of 55 to 59 Gy, both starting on day 1. Escalating doses of 5-FU (96-hour infusion) and CP (2-hour infusion), both on days 1 and 29, were administered according to the following design: starting dose level (0) 5-FU/CP = 800/60 mg/m(2) /day and up to dose level (+2) 5-FU/CP = 1000/80 mg/m(2) /day.