Clinical outcomes associated with bevacizumab-containing treatment of metastatic colorectal cancer: the BRiTE observational cohort study.

BACKGROUND: The Bevacizumab Regimens' Investigation of Treatment Effects (BRiTE) study is a prospective, observational cohort study designed to elucidate safety and effectiveness outcomes associated with bevacizumab combined with chemotherapy as used in clinical practice for first-line treatment of metastatic colorectal cancer (mCRC). PATIENTS AND METHODS: Baseline characteristics, prespecified bevacizumab-related adverse events, and effectiveness data were collected from 1,953 mCRC patients who were receiving first-line treatment including bevacizumab at 248 U.S. sites. RESULTS: At database lock, the median follow-up was 20.1 months. At baseline, 46% of patients were aged >or=65 years and 49% had an Eastern Cooperative Oncology Group performance status score >or=1. Fluorouracil, leucovorin, and oxaliplatin was the most common first-line chemotherapy regimen (56%). Overall rates of bevacizumab-related adverse events in the BRiTE study, such as gastrointestinal perforation (1.9%), arterial thromboembolic events (2%), grade 3-4 bleeding (2.2%), and de novo hypertension requiring medication (22%), were consistent with those reported in randomized clinical trials (RCTs) of bevacizumab in first-line mCRC treatment. The median progression-free survival (PFS) and overall survival (OS) times were 9.9 (95% confidence interval [CI], 9.5-10.3) months and 22.9 (95% CI, 21.9-24.4) months, respectively. CONCLUSION: The median PFS and OS durations and safety profile of bevacizumab in the BRiTE study were similar to those in RCTs of bevacizumab plus chemotherapy in first-line mCRC patients. The observations from the BRiTE study complement and expand upon RCT data, providing clinical information in a large cohort of bevacizumab-treated patients and subgroups such as the elderly.

Gastrointestinal perforation associated with bevacizumab use in metastatic colorectal cancer: results from a large treatment observational cohort study.

BACKGROUND: Bevacizumab prolongs overall and progression-free survival when added to fluorouracil-based chemotherapy in patients with metastatic colorectal cancer in randomised controlled trials (RCTs). However, gastrointestinal perforation (GIP) occurs in 1-2% of treated patients. We sought to describe the incidence, temporal pattern, outcomes and potential risk factors for GIP in a large, community-based observational cohort study of patients treated with bevacizumab. PATIENTS AND METHODS: Baseline patient and tumour characteristics, including potential GIP risk factors, were collected at study entry. Treatment, targeted adverse events, progression events and survival data were recorded every 3 months. Detailed clinical information was collected for all patients experiencing a GIP event. Effects of baseline risk factors on GIP risk were investigated using Cox proportional hazards regression. RESULTS: Of 1953 evaluable patients followed for a median of 20.1 months, 37 (1.9%) experienced GIP. Most GIP events were surgically managed with successful outcomes; four events were fatal. The majority of GIP events (26/37) occurred ≤6 months after starting bevacizumab (median, 3.35 months). Univariate and multivariate analyses showed that age ≥65 years was significantly associated with lower GIP risk. In multivariate analyses, intact primary tumour and prior adjuvant radiotherapy were significantly associated with increased risk of GIP within 6 months after starting bevacizumab. A regression analysis that assessed the risk of GIP over time showed no cumulative risk associated with bevacizumab exposure. CONCLUSION: The observed rate of GIP in this large, community-based experience was consistent with rates reported in RCTs. Most events were successfully managed with surgical intervention.