Phase II trial of FOLFOX6, bevacizumab and cetuximab in patients with Colorectal Cancer

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Background: Bevacizumab (B) + FOLFOX is widely accepted as a standard first-line therapy for metastatic colorectal cancer (mCRC). Recent treatment strategies have included the use of targeted therapies combined with chemotherapy to improve efficacy and to reduce chemotherapy-related toxicities. This Phase II study assesses first-line mFOLFOX6 + B + cetuximab (C), a monoclonal antibody approved for use in irinotecan-refractory mCRC. Methods: All pts had ECOG PS = 1, normal bone marrow, hepatic and renal function. Pts received mFOLFOX6 + B (5mg/kg) biweekly and C weekly (initially at 400 mg/m2, then subsequent doses at 250 mg/m2). Tumor assessment by imaging was done every 8 weeks. Primary endpoints are response rate, progression free-survival (PFS), overall survival (OS), and safety. The regimen would be considered promising if there were = 32 responses, or if = 60% of pts were progression-free for at least 8 months. Results: 67 pts (37 males, 30 females) were enrolled from 12/04–11/06. Median age was 57. Toxicities included Grade 4: neutropenia (6%), thrombosis/embolism (5%). Grade 3: neutropenia (13%), rash (13%), fatigue (11%), diarrhea (11%), abdominal pain (6%), neuropathy (5%), infection with ≤ Grade 2 ANC (4.5%). There were 2 deaths, 1 due to neutropenia and diarrhea and 1 to pulmonary fibrosis. As of 12/06, 9 pts were too early to evaluate. Of the remaining 58 pts, there were 32 responses (55%; 95% CI: 42%, 68%), including 3 CRs and 29 PRs; Median PFS was 9.6 months (95% CI: 8.8, 13.9 months), 71% were progression-free for at least 8 months, and median OS was not reached after a median follow-up of 11.4 months (range 1.5–25.2 months). Conclusions: Treatment with mFOLFOX6+ B + C met the pre-specified criteria for objective response and PFS to be considered promising. This regimen is associated with an acceptable toxicity profile and merits further evaluation. Supported by N01-CA-62204.

No significant financial relationships to disclose.