Successful treatment of experimental murine Trypanosoma brucei infection with topical melarsoprol gel.

Melarsoprol gel applied topically (0.1 mL for at least 2 d) can cure late-stage Trypanosoma brucei brucei and T. b. rhodesiense infections in mice. The best regimen was 3 applications at approximately 0, 6, and 24 h. The melarsoprol gel retained its activity at room temperature for at least 63 d. There was only minimal skin irritation and no sign of toxicity.