Rate of microbiological contamination of multi-use vials of bevacizumab and risk of endopthalmitis

Abstract
Introduction To determine the rate of microbiological contamination in multi-use vials of bevacizumab used for multiple intravitreal injections and to determine the rate of endophthalmitis in patients who received intravitreal injections from these vials. Methods Eighteen 100-mg (4 mL) vials of bevacizumab (Avastin; F. Hoffmann-La Roche Ltd. Switzerland) were used for 327 intravitreal injections in period of 18 months. These vials were stored in refrigerator at 2 – 8°C for 30 days. From each vial, two samples of 0.05ml of avastin was withdrawn with the help of 1ml syringe at 7 and 30 days after the opening the vial. These samples were send for bacterial and fungal staining and culture. 327 patients who received intravitreal injections were monitored for signs and symptoms of inflammation or endopthalmitis. Results No evidence of microbiological contamination was detected in 18 vials sent for microbiological staining and culture. 327 patients who received intravitreal injections from these vials did not showed any signs or symptoms of inflammation or endopthalmitis. Conclusions Using the muti-use vials of bevacizumab for intravitreal injections which are stored for up to 30 days in refrigerator at 2–8°C is safe.