Introduction of halofantrine for malaria treatment

Abstract

The spread of drug-resistant Plasmodium falciparum infections has emphasized the need to develop new antimalarial compounds. Chloroquine resistance has now been confirmed in over 50 countries, and many other drugs used to treat acute infections are becoming of limited use. Recent reports from Thailand suggest that even quinine resistance is increasing to serious levels, and the use of mefloquine — the most recently introduced antimalarial — is already meeting problems there. The onset of drug resistance in P. falciparum observed in the early 1960s, together with the malaria risk to troops during the Vietnam war, stimulated a huge US effort in synthesizing and testing new antimalarials. More than 250 000 compounds were tested in the antimalarial drug development programme o f the US Army Research and Development Command (Walter Reed Army Institute for Research). Two important compounds emerged from this extensive programme — me floquine, already introduced for use in SE Asia, and halofantrine, now completing clinical trials (see Box 1).