Phase 1 Study of Induced Blood-Stage Malaria in Healthy Adults to Assess Safety and Infectivity of Plasmodium Vivax and Evaluate Mosquito Transmission

What this Trial Is About

Researchers are investigating malaria, a disease caused by parasites transmitted by mosquitoes, to understand how it develops in people, how the immune system responds, and how the infection spreads from humans to mosquitoes. This phase 1 study focuses on inducing blood-stage malaria in healthy adults who have never had malaria before, to assess the safety and infectivity of the Plasmodium vivax challenge agent. The research supports future development of vaccines targeting different stages of malaria infection. Participants will receive an intravenous injection of a parasite-containing blood product derived from a cell bank. The study includes a pilot group of at least 2 participants and a main group of up to 50 participants. After inoculation, participants will be monitored closely for symptoms, have daily blood tests, and stay in the clinic for 3 to 6 days for detailed monitoring. They will be exposed to mosquitoes up to 4 times to evaluate transmission. Towards the end of the clinic stay, participants will take chloroquine pills once or twice daily for 3 days to treat the infection. During the study, participants will be contacted daily to check their health and will have follow-up visits 1 and 3 weeks after leaving the clinic. Researchers will perform multiple blood tests and mosquito feeding assays to measure parasite growth, immune responses, and transmission to mosquitoes. The main outcome measured is the safety of the malaria model, with secondary goals including determining appropriate parasite doses and evaluating transmission. The total participation time includes the inoculation, inpatient stay, treatment, and follow-up visits.

Induced Blood-Stage Malaria in Healthy Malaria-Naive Adults to Assess the Safety and Infectivity of Plasmodium Vivax Challenge Agent and Evaluate Transmission in Mosquito Feeding Assays