Accelerating Development of Vaccines for Malaria Elimination Using a Novel Clinical Target Validation Approach
This project aims at supporting the evaluation of novel PE vaccine antigens. Evaluation of these antigens using conventional vaccine development approach is not financially feasible and is unlikely to lead to conclusive outcomes regarding target validation due to the high number of variables (e.g., delivery platform selection, adjuvant selection, variable immune responses, etc.).
The plan is to accelerate target validation for malaria vaccine development by employing a novel, translational research approach that uses mAbs—with demonstrated preclinical functional activity—in CHMI studies. This would enable validation of target antigens, and provide a critical reagent (i.e., protective mAb), prior to engaging in vaccine development efforts.
Highly efficacious vaccines that interrupt malaria transmission (VIMT) are urgently needed to help control malaria and support future elimination and eventual eradication efforts. Pre-erythrocytic (PE) vaccines that prevent mosquito-to-human transmission are highly desirable; they can prevent disease and death, as well as support elimination efforts by preventing infection, thereby breaking the cycle of transmission. Controlled human malaria infection (CHMI) models enable the determination of VIMT-PE vaccine efficacy in small numbers of volunteers.
The PATH Malaria Vaccine Initiative, a program of the US-based global nonprofit organization PATH, initiated a tripartite collaboration with Ehime University and CellFree Sciences Co. Ltd. (both based in Japan) for the identification and initial validation of novel PE malaria vaccine candidates. The concept is to generate monoclonal antibodies (mAbs) directed against a panel of PE antigens that are candidate targets of humoral immunity. These mAbs will be evaluated, via passive transfer studies, for their capacity to protect against parasite infection using the well-established CHMI model.