Preliminary phase II study results of capecitabine (X) + irinotecan (I) + bevacizumab (A) as first-line therapy for patients (pts) with metastatic colorectal cancer (MCRC)
14502 Background: The oral fluoropyrimidine X (Xeloda®) has improved efficacy, safety and convenience compared with 5-FU/LV in MCRC [Van Cutsem et al. Br J Cancer 2004] and early-stage colon cancer [Twelves et al. NEJM 2005]. A recent study showed that I + X q2w is active and well tolerated [Garcia-Alfonso et al. ESMO 2006]. The humanized monoclonal antibody A (Avastin®) targets VEGF and limits tumor angiogenesis. The addition of A to 5-FU/LV/I (IFL regimen) results in significant improvements in survival among pts with MCRC [Hurwitz et al. NEJM 2004]. Replacing 5-FU/LV with X in this combination is a logical step forward. Here we report data from an open-label phase II trial of XIA in MCRC. Methods: Pts with untreated, histologically confirmed MCRC received I 175 mg/m2 i.v. d1, X 1000 mg/m2 orally bid d2–8, and A 5 mg/m2 d1. Treatment was repeated q2w x12 cycles in the absence of disease progression or unacceptable toxicity. Pts without progressive disease after 12 cycles of XIA continued on the same dose of A + X 1500 mg/m2 bid d2–8, q2w. The primary endpoint was progression-free survival (PFS); secondary endpoints were response rate (RECIST), overall survival (OS), safety, and quality of life. Results: 24 out of a planned total of 32 pts have been enrolled. Baseline characteristics are: M/F 50%/50%; median age 53 years (range 30–70); disease stage at initial diagnosis IIIA/IIIB/IV 29%/21%/50%; no. of metastatic sites 1/>1 50%/50%; most common metastatic site liver; prior adjuvant therapy 33% (Mayo 5-FU/LV). Pts received a median of 12 cycles (range 1–18) of XIA. All 24 pts are evaluable for safety and 22 for efficacy. The overall response rate is 77% (4 CR, 13 PR); 2 pts (9%) have stable disease and 3 have progressed. One pt has died. Median PFS and median OS have not yet been reached. The only grade 3 adverse events are diarrhea (13%), fatigue (4%), mucositis (4%), enteritis (4%), ileus (4%); there is one report of grade 4 leucopenia. All other adverse events are mild-to-moderate. Conclusions: The XIA combination appears to be highly active and well tolerated as first-line treatment for MCRC, providing support for further evaluation of this combination. No significant financial relationships to disclose.