Simvastatin treatment showed no prophylactic effect in influenza virus-infected mice

Simvastatin, a cholesterol-lowering drug, is reported to have immunomodulatory properties that attenuated acute lung injury independent of their major lipid lowering effects. Based on these reports, simvastatin is expected to be used for influenza prophylaxis and treatment. The present study evaluated the efficacy of simvastatin against influenza A/PR/8/34 virus infection in a murine model. In a first study, simvastatin was administered orally. To achieve high plasma levels, intraperitoneal application was used in a second study. Survival, body weight loss, viral titers in lung and trachea, and histologic lung injury were measured. Surprisingly, treatment with simvastatin resulted in lower survival rates and in more distinct body mass loss in comparison to virus-infected control mice. Furthermore, the viral load in lungs and tracheas as well as histopathological lesions were not reduced by simvastatin. Overall, these results showed that simvastatin failed to protect mice against influenza virus infection.