Two hundred and sixty seven patients of uncomplicated P. falciparum malaria completed study in a multicentric phase III clinical trial of Arteether. Arteether was given intramuscularly in a dose of 150 mg daily for three consecutive days. Each patient was followed upto 28 days of alpha, beta arteether therapy. The cure rate was 97% with fever clearance time between 1-7 days (24-168 hours) and parasite clearance time between 1-3 days (24-72 hours). Parasite reappearance rate was found to be 3% and reported at only three of the centres. Following the treatment no adverse effect was observed on haematological, biochemical and vital clinical parameters.