Artemether-lumefantrine, mefloquine and atovaquone-proguanil in the treatment of uncomplicated Plasmodium falciparum malaria in travellers: A retrospective comparative study of efficacy and treatment failures

Background: The aim of this study was to evaluate the rates of parasitaemia clearance and the prevalence of treatment failure in patients with uncomplicated Plasmodium falciparum malaria treated with artemether-lumefantrine (AL), mefloquine (MQ), and atovaquone-proguanil (AP). Method: The retrospective descriptive study included adult patients with uncomplicated P. falciparum malaria treated at the University Hospital Bulovka in Prague from 2006 to 2019. Parasitaemia clearance was estimated using a linear regression model. Results: The study included 72 patients with a median age of 33 years (IQR 27-45) and a male to female ratio of 3.2:1. Thirty-six patients (50.0%) were treated with AL, 27 (37.5%) with MQ and 9 (12.5%) with AP. The proportion of VFR and migrants was 22.2% with no significant differences among the three groups. The median time to the parasitaemia clearance was two days (IQR 2-3) in patients treated with AL versus four days in the MQ (IQR 3-4) and AP (IQR 3-4) groups, p < 0.001. The clearance rate constant was 3.3/hour (IQR 2.5-4.0) for AL, 1.6/hour (IQR 1.3-1.9) for MQ, and 1.9/hour (IQR 1.3-2.4) for AP, p < 0.001. Malaria recrudescence occurred in 5/36 (13.9%) patients treated with AL and in no patients treated with MQ or AP. Conclusions: The findings demonstrate the superior efficacy of AL compared to other oral antimalarials in early malaria treatment. However, we observed a higher rate of late treatment failure in patients treated with AL than previously reported. This issue warrants further investigation of possible dose adjustments, extended regimens, or alternative artemisinin-based combinations.