Therapeutic Efficacy of Artemether–Lumefantrine for the Treatment of Uncomplicated Plasmodium falciparum Malaria in Shendi, Sudan: A Prospective WHO Therapeutic Efficacy Study

Abstract

Background: Continuous surveillance of antimalarial therapeutic efficacy is essential for the early detection of emerging drug resistance and for informing national malaria treatment policies. Artemether–lumefantrine (AL) remains the first-line treatment for uncomplicated Plasmodium falciparum malaria in Sudan; however, periodic therapeutic efficacy monitoring in accordance with World Health Organization (WHO) recommendations remains necessary. Objective: This study evaluated the therapeutic efficacy and parasitological response of artemether–lumefantrine among adults with uncomplicated P. falciparum malaria in Shendi, Sudan. Methods: A prospective WHO therapeutic efficacy study was conducted among 100 adults aged 18–65 years with uncomplicated P. falciparum malaria. Participants received standard weight-based artemether–lumefantrine therapy and were followed for 28 days according to WHO therapeutic efficacy guidelines. Clinical and parasitological responses were assessed on scheduled follow-up days, including Days 3, 7 and 28. The primary outcome was the uncorrected Day-28 adequate clinical and parasitological response (ACPR), because PCR genotyping was not performed to distinguish recrudescence from reinfection. Results: All 100 enrolled participants completed the 28-day follow-up. Fever resolved rapidly after treatment, and parasite clearance was observed in most patients by Day 3; however, 17% had persistent parasitaemia on Day 3. The uncorrected Day-28 ACPR was 90.0% (95% CI: 82.4%–95.1%), whereas 10.0% experienced recurrent parasitaemia during follow-up. Because PCR genotyping was not performed, recurrent infections could not be classified as recrudescence or reinfection. Conclusions: Artemether–lumefantrine demonstrated a 90% uncorrected Day-28 therapeutic response in this study population. However, treatment efficacy should be interpreted cautiously because PCR correction was unavailable and persistent Day-3 parasitaemia was observed in a proportion of patients. Continued therapeutic efficacy surveillance, including molecular genotyping in accordance with WHO recommendations, is warranted to monitor antimalarial drug performance and detect early signals of emerging resistance.