Preliminary efficacy trial of Cymelarsan, a novel trypanocide, in camels naturally infected with Trypanosoma evansi in Kenya

The novel trypanocide Cymelarsan (Mel Cy. RM110; Rhone Merieux, France) was shown to have therapeutic activity against Trypanosoma evansi in naturally infected camels in Kenya, at dose rates ranging between 0.2-1.2 mg/kg body weight. Systemic and local reactions were mild and transient. Mel Cy is a trivalent arsenical patented in 1985 under the trade name Cymelarsan which is currently being evaluated as a trypanocide. It has activity against the Trypanozoon subgenus of trypanosomes and has previously been reported to be active against T. evansi in camels in Mali and Ethiopia. The present study aims to confirm these observations for T. evansi infected camels in Kenya and to evaluate the efficacy of a range of dose rates.