In vitro activity of commercial formulation and active principle of trypanocidal drugs against bloodstream forms of Trypanosoma brucei gambiense

Abstract

The in vitro trypanocidal activities of 4 commercial formulations Ornidyl®, Pentamidine isethionate®, 
Germanin® and Lampit® and their corresponding active principles (Dl-α-difluoromethylornithine, 
pentamidine isethionate, suramine and 5-nitrofuran) were compared against Trypanosoma brucei 
gambiense. Differences of minimum inhibitory concentration (MIC) were observed between Ornidyl® 
and Dl-α-difluoromethylornithine and between Lampit® and 5-nitrofuran. For RO 15 strain and the 
comparison of Ornidyl®/ DFMO, the MIC when using the commercial drug was more than twice the MIC 
value obtained with the active principle. For all 3 trypanosome strains, MICs were identical for Lampit® 
and 5-nitrofuran but the MIC with the commercial formulation was twice the MIC obtained with the 
active principle. The active principles, rather than commercial formulations, should be used for 
standardization of in vitro assay protocols.