This is a phase 2b clinical trial in malaria-exposed individuals to assess the immunogenicity, safety, and efficacy of the two vaccines in the context of controlled human malaria infection, P. falciparum sporozoite challenge (PfSPZ Challenge).

A total of 64 participants will be enrolled for challenge and divided into four groups as follows:

20 participants to receive R21/Matrix M (R21/MM) with intradermal PfSPZ Challenge;

20 participants to receive viral-vectored ME-TRAP with intradermal PfSPZ Challenge;

10 participants to receive R21/MM with direct venous inoculation PfSPZ Challenge; and

14 participants comprising of the control group with intradermal PfSPZ Challenge.

Blood tests and clinical assessments will be conducted to screen out participants with health conditions that may impact participation in the study.