Results of a Phase II Trial of Cetuximab plus Capecitabine/Irinotecan as First-Line Therapy for Patients with Advanced and/or Metastatic Colorectal Cancer

Background: XELIRI (capecitabine/irinotecan) is effective and well tolerated in metastatic colorectal cancer (mCRC). Cetuximab is active in mCRC alone or with chemotherapy. This study evaluated cetuximab plus XELIRI in first-line treatment of mCRC. Patients and Methods: Subjects had histologically confirmed unresectable colorectal adenocarcinoma (with T4 lesions) after preoperative chemoradiation and/or metastases. Treatment was capecitabine 1700 mg/m(2) (850 mg/m(2) orally twice a day on days 1-14 for 3 weeks), irinotecan 200 mg/m(2) intravenously (I.V.) on day 1 every 3 weeks, and weekly cetuximab (initially 400 mg/m(2) I.V. [120 minutes], subsequently 250 mg/m(2) [30 minutes]). Results: Baseline characteristics (N = 70): 43 men (61%); median age, 61.5 years; Eastern Cooperative Oncology Group performance status 0/1 = 66%/34%; 94% adenocarcinoma. Previous therapy: surgery (91%), chemotherapy (14%), or radiation therapy (7%). Responses (patients completing 2 cycles): complete response (5.7%), partial response (37.7%), stable disease (43.4%), and progressive disease (PD; 13.2%); 16 patients discontinued early (n = 4 allergic reaction, n = 2 withdrew consent, n = 2 death, and n = 8 other adverse events [AEs]). The overall per-protocol response rate was 43.4% (34% intent to treat [ITT]; disease control rate, 86.8%; 69% ITT). The median time to progression was 8.1 months (range, < 1-27.0 months), and the median time to response was 1.6 months (range, 1.1-8.4 months). The median survival was 20.5 months, and 45.7% of patients remain alive. Of the 38 deaths, 84% were because of PD. No death was treatment related. The most frequent grade 3/4 treatment-related AEs included diarrhea, neutropenia, and nausea/vomiting; 32% of patients required dose reductions. All patients are off the study primarily because of PD (34.3%) or AEs (40.0%). Conclusion: In summary, XELIRI plus cetuximab is a promising regimen that merits further study for first-line mCRC.