The use of Erlangen diamidine 98/202 in relapsing Trypanosoma brucei infections in mice.

Mice infected with T. brucei GVR 23/1 or T. brucei GVR 35/1 for 21 days were treated with the Erlangen diamidine 98/202 (6-amidino-2-[4' amidino-phenyl] thionaphthene-dilacate) at either 5 mg/kg or 35 mg/kg. At both these dose levels the parasites were initially cleared from the circulation although the infections eventually relapsed due to reinvasion from the central nervous system. If the 98/202 therapy is followed by treatment with 5-nitroimidazole only a small number of mice are permanently cured. Adverse reactions, especially at the 35 mg/kg dose level, were noted in one experiment. The Erlangen diamidine given to infected mice three days after infection was able to permanently cure both Trypanosoma brucei stabilates.