Objective: To compare the cytotoxic response with respect to different Shengmai injections manufactured by different manufacturers and to find the main reasons that cause the differences.
Method: L929 cells were cultured with various Shengmai injections which were incubated into serum-supplemented minimum essential medium at different doses. The cellular morphology was observed by phase contrast inverted microscopy and proliferation of the cells was examined using mitochondrial function methyl thiazolyl tetrazolium (MTT) assay. Relative growth rate (RGR) was calculated. Moreover, cytotoxicity was evaluated.
Result: For Shengmai injections manufactured by 8 manufacturers, cytotoxicity was high, Class 4. The EC value of sample A was high than other samples. This result indicated that sample A is much more toxic than other samples. For the excipients of Shengmai injections, when the concentration of tween 80 is 0.5% of composition of drug products, cytotoxicity was classified as 3-4; while the concentration of tween 80 is 0.062 5% of composition of drug products, the cellular toxicity was classified as 1 (no cellular toxic response). The content of tween 80 of shengmai injection is different during different factories; some of it is higher than 0.5%.
Conclusion: Cytotoxic results of these various injections were significantly different because of different manufacturers of drug substance and manufacturing process. As an excipient of injection, it showed cytotoxicity when the concentration is higher than 0.062 5%. The content of tween-80 and the degree of cytotoxicity in different Shengmai injections may have a positive correlation.