Evaluation of toxicity and effectiveness of the anti-malaria preparation mefloquine with respect to SARS-CoV-2 in experiments on animals

The aim of the study was to clarify the toxicity of mefloquine and to evaluate the effectiveness of its use for Syrian hamsters infected with sARS-Cov-2.Material and methods. The experiments were performed on 96 Syrian hamsters. The toxicity of mefloquine was determined with a single administration, as well as with a course of administration at doses comparable to therapeutic for humans. To study the effectiveness of the drug against SARS-CoV-2 infection, a comprehensive indicator of the state of lung tissue and a comparison of the dynamics of viral load in the lungs were used.Results. The LD50 of mefloquine with a single oral administration is 817 mg/kg, the maximum tolerated dose is 600 mg/kg. When administered for 7 days at a cumulative dose of 900 mg/kg, no death was observed. Administration of mefloquine to animals infected with SARS-CoV-2 was accompanied by a decrease in the severity of lung damage and a faster decrease of viral load in the lung tissue.