Objective: To evaluate the in vitro and in vivo antituberculous activities of clofazimine.
Methods: The MIC of clofazimine against H(37)Rv and 30 MDR-TB clinical strains were determined by microplate Alamar blue assays. Female BALB/c mice were infected with M. tuberculosis H(37)Rv (10(5) CFU/mouse). The infected mice were divided into the following groups: a control group, treated with saline 5 times per week; isoniazid treatment group, 25 mg/kg, 5 times per week; clofazimine 20 mg/kg group, 5 times per week; clofazimine 10 mg/kg group, 5 times per week, and another clofazimine 20 mg/kg group, but the drug was given twice weekly. The drugs and saline were administered by gavage, and the treatment lasted for 30 days after infection. Five mice from each group were assessed for bacterial CFU count and organ weights of the lung and spleen on day 30.
Results: The MIC of clofazimine against M. tuberculosis H(37)Rv was 0.12 - 0.24 microg/ml, and the MIC against 30 MDR-TB clinical strains ranged from 0.12 to 1.92 microg/ml. In the murine model, clofazimine treatments decreased the CFU by 1.39 - 2.92 lg as compared to that of the control group on day 30.
Conclusions: Clofazimine has in vitro and in vivo activities against M. tuberculosis.