Pilot study of fixed-dose bevacizumab (200 mg) for solid malignancies

Abstract

e14600 Background: We report our initial experience with fixed dose bevacizumab at 200mg (approximately 3mg/kg). Phase I studies suggested that an optimal dose for phase II studies with bevacizumab is 3mg/kg and that circulating VEGF was undetectable at 0.3mg/kg. (Gordon et al. JCO 2001) We proposed a fixed-dose regimen of bevacizumab which we hypothesized would yield equivalent response rates with reduced toxicities and cost versus higher-dose regimens. Patients with advanced malignancies for whom bevacizumab would be indicated were analyzed. Methods: 15 patients were treated with 200mg bevacizumab in combination with antineoplastic therapy. 6 patients had NSCLCa, 8 patients had Colorectal cancer, and 1 patient had BRCA. Results: 15 patients are evaulable for response and have completed a total of 234 doses of bevacizumab (median number of doses =13) with no grade III/IV toxicity, or bevacizumab associated toxicities seen. No grade III or greater hypertension was observed. Proteinuria was not formally assessed, but no grade 3 or greater proteinuria was reported. All patients are evaluable for response with overall response rate of 33% (5/15). With a median follow-up (from the start of bevacizumab) of 452 days (222–1,699 days), median survival has not been reached with only 2 deaths. Conclusions: Fixed dose bevacizumab appears to be effective, less toxic, significantly less expensive and supported by biologic rationale and prior phase I studies and warrants further investigation. Additional patients will be accrued in a prospective phase II trial. [Table: see text]