Background Recently, the World Health Organization (WHO) has recommended to extend the seasonal malaria chemoprevention (SMC) with Sulfadoxine-pyrimethamine plus amodiaquine (SP-AQ) strategy to school aged children and to use alternative artemisinin-based combination therapies (ACTs). There is less data on the efficacy of ACTs in SMC and their impact on the selection of drugs resistant parasites. The aim of this trial was to assess the efficacy of Dihydroartemisinin-Piperaquine (DHA-PPQ) in school aged children during and after SMCs and to assess the prevalence of resistance markers to ACT, amodiaquine and piperaquine.

Methods We conducted a randomized trial from September to December 2020 including 345 children of 6–15 years old. Study participants were randomized in 1:1:1 ratio to receive monthly 3 consecutives doses of DHA-PQ, SP-AQ or control drug (Albendazole). Study drugs were administrated for 3 consecutive days at each SMC round. All drugs were administrated under direct supervision of a study pharmacist. Dried blood specimens (DBS) were collected at the start of each SMC round and 7 days after the first dose of SMC. Dynamic of malaria parasites prevalence and the resistance markers to drugs were assessed by molecular assays in DHA-PQ, SP-AQ and control arms over 4 months of SMC and 8 months following SMC using q-PCR assay.

Results Preliminary data from 100 participants showed a significant decrease in the prevalence of Plasmodium falciparum parasites carriage from 67% to 10% at days 1 and 31 after the first SMC round. The prevalence remained low during SMC follow-up period. Molecular assays of resistance markers are ongoing. Full results will be presented at the meeting.

Conclusion DHA-PPQ is suitable for SMC, assessment of parasites prevalence and resistance markers selection is ongoing.