INVITRO ACTIVITY OF PYRONARIDINE AGAINST AFRICAN STRAINS OF PLASMODIUM-FALCIPARUM

The in vitro activity of pyronaridine was determined and compared with the activity of monodesethylamodiaquine and amopyroquine against 31 clinical isolates and two clones of Plasmodium falciparum originating from Central and West Africa using a semi-micro drug susceptibility test. Pyronaridine and amopyroquine were 2.5 and four times less active, respectively, against the highly chloroquine-resistant clone, than against the chloroquine-susceptible clone but were equally active against chloroquine-susceptible and chloroquine-resistant clinical isolates. Compared with chloroquine-susceptible isolates, monodesethylamodiaquine was three times less active against chloroquine-resistant parasites. Pyronaridine is highly active against chloroquine-resistant strains of P. falciparum and may be a promising candidate for the treatment of resistant malaria.