Testing and Treatment to Prevent Plasmodium Vivax Malaria Relapses in Ethiopia and Madagascar A Cluster-Randomized Phase 3 Trial

What this Trial Is About

Researchers are investigating a new approach to target Plasmodium vivax malaria, which persists due to dormant liver stages called hypnozoites that can cause relapses weeks to months after initial infection. This cluster-randomised Phase 3 trial in Madagascar and Ethiopia aims to evaluate the feasibility, acceptability, and effectiveness of Plasmodium vivax Serological Testing and Treatment PvSeroTAT to identify and treat individuals recently exposed to the parasite and reduce relapses and transmission. The study involves 48 clusters randomly assigned to either the PvSeroTAT intervention or a control arm. In the intervention clusters, participants undergo two rounds of serological testing at baseline and six months to detect antibodies indicating recent infection. Those with positive results receive targeted treatment with primaquine plus chloroquine or artesunate-amodiaquine depending on the country, after confirming normal G6PD enzyme activity and no contraindications. Control clusters receive serological testing without treatment. Malaria incidence is monitored passively for up to 18 months after the first intervention, and cross-sectional surveys with blood sampling occur at months 12 and 18 to assess malaria prevalence. Participants will be monitored for side effects and adherence during the first week of treatment, with blood tests to check hemoglobin levels and detect any hemolysis. The main outcome measured is the proportion of individuals with detectable P. vivax infections six months after the second intervention round. Secondary outcomes include infection prevalence and clinical malaria incidence at various timepoints, safety assessments, and treatment coverage. The study runs from May 2025 to April 2027, with ongoing monitoring and surveys to understand the impact of this targeted serological testing and treatment approach.

Serological Testing and Treatment for Plasmodium Vivax Malaria: a Trial in Ethiopia and Madagascar