Pharmacokinetics, Trypanosoma brucei gambiense Efficacy, and Time of Drug Action of DB829, a Preclinical Candidate for Treatment of Second-Stage Human African Trypanosomiasis

In Vitro and In Vivo Evaluation of 28DAP010, a Novel Diamidine for Treatment of Second-Stage African Sleeping Sickness

“…In vitro time of drug action was monitored using isothermal microcalorimetry. With this method, the time of drug action on a parasite population can be determined on a real-time basis (21,23). The strain STIB900 was used as a representative for T. b. rhodesiense and STIB930 (and sometimes additionally ITMAP141267) for T. b. gambiense.…”

“…For studies of the drug effect on different parasite densities in the inoculum, the parasite density was reduced to 1 ϫ 10 4 /ml of bloodstream trypanosomes and supplemented with 28DAP010 at the desired concentrations. Inhibition of growth and viability was compared with that in the samples containing the standard inoculum of 5 ϫ 10 4 /ml of bloodstream trypanosomes and the same drug concentrations (23). Each experiment was set up in triplicate and repeated once.…”

“…The 50% inhibitory concentrations (IC 50 s) were determined using the alamarBlue assay as described by Räz et al (26), with a 3-day drug exposure and minor modifications as described previously (23). Assays were carried out at least three times independently and each time in duplicate.…”

“…Coefficients of variation were less than 50%. Different culture and assay media were used for T. b. gambiense and T. b. rhodesiense, as previously described by Wenzler et al (23).…”

“…The drug-free control samples (drug free, wash-out) were washed identically to the drug-containing samples. Each 24-h exposure experiment was set up in triplicate and repeated once (23).…”