Bevacizumab plus irinotecan/5-FU/leucovorin for treatment of metastatic colorectal cancer results in survival benefit in all pre-specified patient subgroups

Abstract

3617 Background. Bevacizumab [Avastin (BV)], a recombinant, humanized monoclonal antibody against VEGF, has demonstrated efficacy and safety when added to irinotecan/5-fluorouracil/leucovorin (IFL) chemotherapy as first-line therapy for metastatic colorectal cancer (CRC). The results of the primary analysis of a randomized phase III trial demonstrated that the addition of BV to IFL resulted in significant improvement in survival compared with IFL alone (p=0.00004; median survival increased from 15.61 to 20.34 months). Additional sub-group analyses were performed to evaluate the effects of baseline risk factors on survival. Methods. The effects of demographic and baseline prognostic characteristics and selected baseline laboratory values on duration of survival, PFS, and objective response rate were examined. Patient characteristics included baseline ECOG performance status, number of organ sites with metastases, site of primary tumor, age, sex, race, prior adjuvant chemotherapy, prior radiotherapy, duration of metastatic disease, years since diagnosis of CRC, baseline sum of longest diameters of target lesions, baseline levels of albumin, alkaline phosphatase, and LDH. Descriptive summaries of duration of survival and PFS were produced for each level of the categorical variables listed above for each treatment arm. These descriptive summaries consisted of the hazard ratio from unstratified Cox regression and Kaplan-Meier estimates of median time to the event. Results. 815 patients were randomized to receive either IFL + placebo or IFL + BV. A survival benefit in the IFL/BV arm was seen across all patient subgroups compared with the IFL/placebo arm (see table). Conclusion. The addition of Bevacizumab to IFL chemotherapy results in prolonged survival in multiple sub-groups. Author Disclosure Employment or Leadership Consultant or Advisory Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Genentech Genentech Genentech Genentech Genentech