Malaria Therapeutic Efficacy Study, Rwanda

WHO recommends that Therapeutic Efficacy Studies (TES) for 1st and 2nd line antimalarial medicines should be routinely carried out and data made available for decision-making due to the threat of emergence and spread of artemisinin resistance in malaria-endemic countries, especially in Africa. The Rwandan Ministry of Health (MOH) in 2006 adopted WHO-approved artemether-lumefantrine (ALN) as the first-line drug for the treatment of uncomplicated Plasmodium falciparum malaria. A clinical trial carried out in 2004-2005 in Rwanda showed that ALN was very efficacious in children although efficacy varied in different parts of the country. ALN efficacy was shown to remain high in TES conducted in 2012-2015 and in 2018. However, both studies found a molecular marker of parasite resistance to artemisinin (included delayed parasite clearance associated with artemisinin resistance in one site in 2018) and both studies also found high prevalence of markers associated with tolerance to lumefantrine. The clinical efficacy of ALN therefore needs to be regularly monitored in Rwanda to ensure this first line treatment is still efficacious. Given the detection of antimalarial resistance markers in recent TES, it is also important for Rwanda MOH to determine the efficacy an additional ACT that could be considered for adoption as a second line or alternative first line treatment. This study will monitor the efficacy of ALN (which has been used in Rwanda for the last 14 years) and dihydroartemisinin-piperaquine (DHA-PPQ), another WHO-approved ACT for the treatment of uncomplicated malaria which has not been used in Rwanda.

In line with the WHO recommendation, Jhpiego Impact Malaria project in Rwanda, with funding and technical oversight from US President's Malaria Initiative (PMI) through USAID and CDC, will be supporting the Rwanda MOH Malaria and Other Parasitic Diseases Unit (MOPDD) of the Rwanda Biomedical Center (RBC) to conduct a TES to monitor the efficacy of ALN and DHA-PPQ in children with uncomplicated clinical malaria in rural Rwanda. The study is being conducted by Rwanda MOH MOPDD, with technical support and funding by PMI-USAID through the Jhpiego Impact Malaria project in Rwanda.

Objective: To evaluate the efficacy of artemether-lumefantrine (ALN) and dihydroartemisinin-piperaquine (DHA-PPQ) in children with uncomplicated clinical malaria in rural Rwanda

Study Sites: The study will be conducted in three sentinel sites - Rukara, Bugarama and Masaka rural health centers- where antimalaria efficacy studies are always carried out in Rwanda because of the intensity of malaria transmission. Different levels of artemisinin resistance have been identified in two of these three (Rukara and Bugarama) in previous studies. At each site, there will be two arms: one for ALN and one for DHA-PPQ.

Study Design: The study will be a two-arm, open-label trial in which patients (children aged 6 months to 59 months) with uncomplicated P. falciparum malaria will be treated with supervised doses of ALN or DHA-PPQ. Children will be followed for 28 days after treatment for ALN and 42 days after DHA-PPQ. Data on molecular markers of artemisinin resistance will be collected at all sites. The study will be conducted at three sites in Rwanda with historically different efficacy profiles to antimalarials, including ACTs.

The primary endpoint is the clinical and parasitological cure by day 28 (ALN) and day 42 (DHA-PPQ) post-treatment.

Study Period: March 2021 to October 2022

Sample Size: At each site, 88 patients per treatment arm (allowing for 20% loss to follow-up) would be enrolled. In total, we will enrol 528 patients in our study.

Treatment(s) and follow-up: All children enrolled in the study will be admitted to a health centre for three days to ensure adherence to treatment regimen, and detect possible adverse events. Clinical and parasitological parameters will be monitored over a 28-day follow-up period to evaluate ALN efficacy, and over a 42-day follow-up period to evaluate DHA-PPQ efficacy.

Exploratory endpoints: to characterize molecular markers of artemisinin and partner drug resistance in all three sites and the clinical (parasite clearance) and in vitro phenotypes of resistance in two of the three study sites: Rukara and Masaka.