Therapeutic efficacy of artesunate-amodiaquine and artemether-lumefantrine for the treatment of uncomplicated plasmodium falciparum malaria in children under five years in Guinea

Abstract

Artemisinin-based combination therapy (ACT) is the first-line antimalarial treatment for uncomplicated Plasmodium falciparum infection in Guinea. This study prospectively evaluated the efficacy and tolerance of two ACTs used in the management of uncomplicated P. falciparum malaria cases in children under five years of age in two sites in Guinea. We conducted a two-arm, randomized therapeutic efficacy study evaluating artesunateamodiaquine (ASAQ) and artemether-lumefantrine (AL) during a 28-day follow-up period. Data were collected at two health centers (located in Labé and Mafèrinyah Health Districts) between August 2015 and April 2016. Parasites from pre-treatment and day-of-failure samples from late treatment failures were genotyped and compared using neutral microsatellite markers to distinguish recrudescences from reinfections. A total of 421 subjects were enrolled, including 212 in the ASAQ arm and 209 in the AL arm; eight patients were lost to follow-up. Seven adverse events were reported, including two deaths that were not drug related. No patients had detectable parasitaemia on day 3. Of 22 late treatment failures, 20 were classified as reinfections and 2 as recrudescences. Across both sites, the therapeutic efficacy before molecular correction was 96% (95% confidence interval: 92-98%) for ASAQ and 93% (89-96%) for AL, and after molecular correction it reached 100% (96-100%) for ASAQ and 99% (97-100%) for AL. The two therapeutic combinations were effective for the treatment of uncomplicated P. falciparum malaria in children under five years in Guinea. Surveillance should continue to detect early antimalarial drug resistance in Guinea’s fixed sentinel sites.