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

Single-center, open-label, phase 1 study to characterize the safety and infectivity of Plasmodium vivax (P. vivax) challenge agent for induced blood-stage malaria (IBSM) in malaria-naive participants at the NIH Clinical Center (NIHCC). Challenge agent derived from 2 cell banks of cryopreserved blood-stage P. vivax (PvHMB-CCE001 and PvHMB-CCE002) will be administered intravenously. A minimum of 2 participants per bank will undergo IBSM to establish the safety and infectivity of the challenge agent. Additional participants, with a ceiling of 16 per bank undergoing IBSM, will be enrolled to further develop the model including to evaluate transmission to mosquitoes using feeding assays and assess the host response to P. vivax infection. All participants who receive challenge agent will undergo antimalarial treatment. Qualification of the IBSM model in transmission assays is a requisite goal in supporting future studies of transmission-blocking vaccines (TBVs).

Challenge agent derived from each of the 2 banks (PvHMB-CCE001and PvHMB-CCE002) will be assessed first in a pilot group of at least 2 participants, then subsequently in a main group with participants receiving inoculations in cohorts of up to 10 individuals based on logistical considerations including the capacity of clinic resources. The dose of the challenge agent may be adjusted if needed to generate reliable IBSM.

Visit ClinicalTrials.gov for details.