Efficacy of bevacizumab plus chemotherapy as first-line treatment of patients with metastatic colorectal cancer: Updated results from a large observational registry in the US (BRiTE)

Abstract

3537 Background: Bevacizumab (BV) prolongs overall survival and progression-free survival (PFS) when added to standard chemotherapy (CT) in patients with metastatic colorectal cancer (mCRC). BRiTE is a large, community-based observational registry of patients with mCRC receiving BV plus first-line CT. Safety and efficacy information in unselected patients with mCRC are collected. Chemotherapy regimen choice is at the physician’s discretion. Methods: 1968 patients receiving BV plus first-line CT were enrolled at 248 sites in 49 states between Feb 2004 and Jun 2005. Patients are followed for up to 3 years, with data reporting every 3 months (mo) including disease status as assessed by investigator using his/her method of choice. Patients were grouped twice by CT. Cox regression models, adjusted and unadjusted for treatment assignment, were used to identify baseline characteristics (BC) and differential chemotherapy effects on PFS. Results: Cohort demographics were consistent with the NCI Surveillance, Epidemiology, and End Results (SEER) database for mCRC. Median study follow-up was 10 months by Nov 4, 2005. CT regimens included FOLFOX (55.8%), FOLFIRI (14.1%), and IFL (9.7%). Based on observed progression events (n=800) or deaths (n=123), projected median PFS is 11.3 mo (95% CI: 10.4–11.7). Median PFS was comparable in patients treated with CT regimen based on irinotecan (11.3 mo), oxaliplatin (11.4 mo), or neither (10.2 mo) (CT Grouping 1); or 5FU infusion (11.5 mo), 5-FU bolus (9.7 mo), or capecitabine (11.6 mo) (CT Grouping 2). Significant BC in adjusted and unadjusted models are ECOG performance status (PS), primary disease site, and albumin, with no significant difference among CT regimens. Conclusions: This large, community-based registry included a patient population with demographics consistent with the SEER database for mCRC. Preliminary median PFS of 11.3 mo compares favorably to that reported in the pivotal trial. Median PFS appears to be comparable for all CTs when combined with BV. Higher baseline albumin, PS of 0, and primary disease site of rectum were associated with improved outcome. [Table: see text]