A new micronized formulation of halofantrine hydrochloride in the treatment of acute Plasmodium falciparum malaria.

The current formulation of halofantrine hydrochloride has poor absorption and bioavailability. A newly developed micronized formulation was evaluated for efficacy, safety and tolerance in the treatment of acute Plasmodium falciparum malaria. The study was conducted at a plantation hospital in northern Tanzania, where chloroquine resistance is common. Sixty in-patients with mild or moderate malaria were treated with 375-750 mg micronized halofantrine hydrochloride given in 3 equal doses, 6 h apart. Patients were followed up for 28 d after therapy. Treatment was associated with rapid parasite clearance (mean clearance time = 34.8 h), fever clearance (mean time = 20 h), and clinical improvement (70% of patients were free of all presenting symptoms within 2 d). The formulation was well tolerated clinically, although 3 patients (5%) developed mild pruritus after treatment which may have been drug-related. Haematological and biochemical studies did not indicate any significant toxicity. One patient, whose immediate recovery was uneventful, was found to have a headache and low parasitaemia 3 weeks after treatment. He was readmitted to the study and treated as before. Parasitaemia, fever and headache cleared rapidly and he remained aparasitaemic for 28 d.