Ro 42-1611 in the treatment of patients with mild malaria: a clinical trial in Nigeria and Burkina Faso.

An open, non-comparative clinical trial was carried out in Nigeria and Burkina Faso to investigate the safety and efficacy of the novel antimalarial arteflene in patients with mild malaria. Patients were males aged 12 to 16 years, with a Plasmodium falciparum count of 10(4) to 10(5) parasites/microliters and a body temperature of 37.5 to 38.5 degrees C. Twenty-three patients received a single dose of Ro 42-1611 (arteflene), corresponding to 25 +/- 2.5 mg/kg bodyweight. Nineteen patients were evaluable for standard efficacy. Efficacy was assessed at 6, 9, 12, 24, 36, 48 and 72 hours, and at seven days, by: reduction in parasitaemia and time to parasite clearance; resolution of fever; and clinical cure (defined as the absence of signs and symptoms of malaria). Adverse events were reported at each assessment point, and laboratory tests were carried out at baseline and at 2 and 7 days. The parasite count was reduced by 50% or more in 89.5% of patients after 48 hours, and 52.6% were completely free of parasites at the same time. Normal temperature was achieved in 89.5% of patients and clinical cure in 75%, after 48 hours. One patient reported mild vertigo and mild pruritus. The lower than expected effect was thought to be due to inadequate storage of the arteflene suspension. There were no withdrawals due to adverse events and no deaths. A single dose of 25 mg/kg arteflene was found to be an effective and well-tolerated treatment for mild P. falciparum malaria.