Evaluation Evaluating the Efficacy of Artemisinin-based Combination Therapies for Treating Plasmodium falciparum Among Children in Osogbo, Nigeria: A Study Conducted 13 Years After ACT Introduction

Background: Malaria continues to pose a significant public health challenge globally, particularly in sub-Saharan Africa, where most cases and deaths occur. Artemisinin-based combination therapies (ACTs), particularly artemether-lumefantrine (AL) and artesunate-amodiaquine (ASAQ), are the most prescribed first-line treatments. However, recent studies have reported reduced efficacy, raising concerns about emerging drug resistance that could threaten malaria control efforts. Given Nigeria’s high malaria burden, continuous monitoring of ACT efficacy is crucial to detect early signs of treatment failure and assess the sustainability of current treatment regimens. Methods: Children aged 6 months to 12 years with uncomplicated P. falciparum malaria were enrolled in a 28-day in vivo trial using the 2009 World Health Organization protocol for monitoring anti-malarial efficacy. They were randomly assigned to receive either AL or ASAQ. The primary outcome measures included the rate of adequate clinical and parasitological response (ACPR), the incidence of treat-ment failures, and recovery from anaemia. PCR correction was achieved by genotyping the merozoite surface protein 2 and glurp genes in paired pre- and post-treatment samples. Genotyping assays for molecular markers of resistance in the pfcrt and pfmdr1 genes were conduct-ed. Statistical analyses employed chi-square and t-tests, with a significant level set at p<0.05. Results: Out of 353 participants, 81 (47.3%) in the ASAQ group and 86 (50.3%) in the AL group completed the study. AL and ASAQ demonstrated high efficacy, with a 98.8% ACPR rate in both treatment groups. Late parasitological failures were observed at a rate of 1.2% in both groups. The day-28 cumulative PCR-corrected efficacy rates for AL and ASAQ were 98.8% (95% CI: 97.1–100) and 98% (95% CI: 95–100), respectively. Adverse events were minimal and consistent across treatment groups. Recovery from anemia was comparable be-tween AL and ASAQ, demonstrating their effectiveness in managing malaria-related anemia. Conclusions: PCR-corrected analysis indicated that AL and ASAQ are effective in treating uncomplicated P. falciparum malaria in Nigeri-an children with high ACPR rates and minimal adverse events. These findings highlight the continued importance of ACTs in malaria man-agement while underscoring the need to explore new therapeutic approaches and drug resistance monitoring strategies. These findings indi-cate that ACTs continue to play an essential role in malaria management, highlighting the need to explore new therapeutic approaches to address emerging drug resistance.