In vitro and in vivo effects of N-methyl-3,5-dichloro-benzylamine hydrochloride on Mycobacterium leprae.

The antimicrobial effects of a new benzylamine, ME-93 (N-methyl-3,5-dichloro-benzylamine hydrochloride), alone and in combination with dapsone and rifampicin, have been evaluated in vitro in cell-free culture system and in vivo in mouse foot pad system. Even at 50 micrograms/ml, ME-93 did not completely inhibit the in vitro growth of M. leprae, and the effects were bacteriostatic. However, there was a synergism when ME-93 was combined with rifampicin, and the effects were bactericidal. Similar findings were also obtained in the mouse foot pad system. Thus, there is a new drug that needs further attention in the chemotherapy of leprosy.