Curative Effects of the Antipiroplasms Amicarbalide and Imidocarb on Trypanosoma brucei Infection in Mice*

Abstract

The babesicides imidocarb and amicarbalide, which have structural similarities to the antitrypanosomatid diamidines, proved active against T. brucei mouse infections. Both drugs cured infections when doses were administered daily for 3 days 24 h post-inoculation (curative dose imidocarb, 10 mg/kg; amicarbalide, 25 mg/kg). Mice were considered cured after survival 30 days longer than untreated infected controls, with no trypanosomes present in blood or CSF smears. Both agents also cured when administered 48 and 72 h after challenge with T. brucei and prolonged the lives of animals 94 h after challenge. The results are discussed regarding the potential of these carbanilides and their precursors, the antitumor phthalanilides, as lead compounds in chemotherapy of mammalian trypanosomiases.