Toby Leslie, M.Sc., of HealthNet TPO Malaria and Leishmaniasis Control Programme, Peshawar, Northwest Frontier Province, Pakistan, and colleagues tested the relative efficacy and safety of two antifolate drugs (sulfadoxine-pyrimethamine and chlorproguanil-dapsone) against P vivax malaria and compared each with chloroquine. There are an estimated 70 million to 80 million cases of P vivax each year, accounting for more than 50 percent of all malaria cases outside Africa. Although rarely fatal, it is a major cause of illness. P vivax malaria was thought to be resistant to treatment with antifolates, an affordable antimalarial class. The study included 767 patients (315 from Pakistan and 452 from Afghanistan) with P vivax malaria. The researchers found that although chloroquine remains the drug of choice, all three therapies effectively cleared parasites by day 14 and were well tolerated. "These drugs may be appropriate for unified treatment where species-specific diagnosis is unavailable, most likely in combination with other drugs."