Last Updated: 02/12/2024
Phase 1 and Phase 2a Clinical Trial:Immunization of Human Volunteers With P. Vivax Irradiated Sporozoites
Objectives
The primary objective of this study is:
To assess the safety and protective efficacy of P. vivax irradiated sporozoite vaccination. This study also aims for following secondary objectives:
- to determine the immune responses and duration elicited by the P. vivax challenge in human Fy(+) volunteers previously immunized with irr-spz, as compared with non-immunized human volunteers;
- to determine the immune responses and duration elicited by irr-spz immunization scheme in human Fy(+) volunteers; comparing it with the same immunization scheme with non irr-spz in Fy(-) participants, and also with controls exposed to the same mosquito bite scheme as that of immunization but using mosquitoes without parasite infection; and
- to study new antigens potentially useful to induce pre-erythrocytic protection against P. vivax malaria infection
Malaria Vaccine and Drug Development Center (MVDC), Colombia
Vaccination with malaria irradiated sporozoites (irr-spz) represents one of the most promising means to prevent the development of pre-erythrocytic stages of human Plasmodia and therefore of preventing malaria disease. Studies conducted in human and animal models have reproducibly demonstrated that this vaccination strategy consistently induces solid sterile protection.
14 Fy(+) human volunteers in the experimental group will be immunized with 1,000-2,000 P. vivax irrad-spz bites. Seven Fy(+) volunteers in the control group will be exposed to non-infected mosquito bites. Six Fy(-) volunteers will be exposed to infective mosquito bites. For the challenge both the immunized and control groups will be exposed to 3 ± 1 infective mosquito bites. Volunteers will be closely monitored post infection and will be treated with antimalarials.
Primary outcome: Three groups are considered to be intervened. Experimental, Control and Fy(-) groups. Comparison will be done between E and C groups for protective efficacy. For immune response tests E vs Fy(-),E vs Fy(-), and Fy(-) vs C, pairs will be compared.
Secondary outcome: The number of subjects reporting any AEs, the occurrence of specifics AEs, and discontinuation due to AEs will be tabulated. Frequency of AEs will be cross-tabulated by group for each immunization session.
ClinicalTrials.gov Identifier: NCT01082341
Study Phase: I/IIa
Study Type : Interventional
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Prevention
Jun 2012 — May 2015
Related Resources
