Safety and Feasibility Study of Controlled Blood-stage Plasmodium Vivax Malaria Infection by Injection of Cryopreserved Infected Red Blood Cells in Healthy Thai Adults

What this Trial Is About

Researchers are evaluating the safety and feasibility of a controlled human Plasmodium vivax malaria infection CHMI in healthy adult Thai volunteers. This study aims to find the best dose of cryopreserved P. vivax infected red blood cells for future studies by experimentally injecting these infected cells into volunteers. The study involves up to 48 participants, who will be closely monitored in a hospital setting, with the goal of understanding the infection process and treatment responses. Participants will receive one of four doses of infected red blood cells, ranging from a whole vial to diluted amounts, administered by injection. Each dose will be tested in groups of volunteers to identify which dose reliably produces infection. The study includes a screening period, a challenge day for infection, a monitoring phase until treatment criteria are met, and a follow-up period lasting one year after treatment. Volunteers will be admitted to the hospital for close monitoring, including daily health checks and blood tests to detect malaria parasites and assess immune responses. After infection is confirmed, blood samples will be taken twice daily until participants meet treatment criteria, at which point antimalarial drugs will be given. Follow-up visits will occur over the next year to monitor health, immune response, and possible parasite transmission. Safety and infection outcomes will be analyzed throughout the study period.

A Controlled Human Vivax Malaria Infection Study Through Inoculation of Infected Erythrocytes