Combination therapy based on artemisinins might not be the ideal treatment for malaria

A paper published in this month's PLoS Medicine suggests that combination therapy based on artemisinins (one of the newer antimalarial classes of drug) might not be the ideal treatment for uncomplicated malaria in Africa.

If used alone, artemisinins will cure the most severe type of malaria - falciparum malaria - in seven days. However, when used on their own, they have a high risk of the malaria coming back and hence must be combined with other antimalarials to work best.

Artemisinins may also slow down development of resistance to the partner drug. But although combinations including artemisinins have been widely advocated, they are expensive and relatively untested in areas where malaria is very frequent.

In a randomised trial conducted at four sites in Uganda, the researchers, led by Grant Dorsey from UCSF, showed that patients treated with a cheaper combination of drugs - amodiaquine and sulfadoxine-pyrimethamine - had at least as good a chance of preventing recurrent malarial infection (defined as either new infections or the previous infection returning) compared with patients treated with artemisinin-based combination therapy. In the sites that had the highest transmission rates the cheaper combination worked better.

The authors conclude that although artemisinin combinations offer great hope for Africa, the ideal combination regimen remains uncertain and cost is a problem. To compare the efficacy of the different therapies, bigger and longer controlled trials are needed in many different conditions.