A study on the contamination of injection bevacizumab on storage of multidose vials

Purpose: The aim of this study is to establish the safety of storage and reuse of bevacizumab vials for 1 week with multiple vial punctures. Methods: This was an experimental microbiological study conducted at tertiary care hospital. The study samples included bevacizumab vials that had been used for injecting patients by the pooling method. Vials were stored and sampled in a manner that replicated their proposed clinical use. Contamination of vials was evaluated on the basis of microbial culture and validated by positive and negative controls. The probability of obtaining such results purely by chance was calculated. Results: A total of 210 samples from 30 vials were evaluated along with 210 positive and 210 negative controls. No growth was seen in any of the bevacizumab samples. The probability of obtaining 210 consecutive sterile samples just by chance is −6 (0.000005547). Conclusion: The vials showed no contamination on storage for 7 days in an ordinary refrigerator. Thus, we conclude that the rate of contamination of bevacizumab vials on storage for 7 days in a refrigerator is likely to be insignificant. The results need to be validated by other studies replicating this protocol.