This Phase 1 study, conducted in malaria-naïve adults in Australia, was designed to determine the safety, reactogenicity, and immunogenicity of merozoite surface protein 2-combination 1 (MSP2-C1) formulated with a water-in-oil adjuvant, ISA 720.
Volunteers were divided into three dose-escalating groups (10 µg, 40 µg, and 80 µg), and received multiple intramuscular vaccinations of MSP2-C1 adjuvanted in ISA 720 at 12-week intervals.
The study was designed with two objectives:
- Assess the safety and reactogenicity of the MSP2-C1/ISA 720 vaccine in malaria-naïve adults by monitoring for occurrence of solicited signs and symptoms, occurrence of unsolicited symptoms, and the occurrence of serious adverse events during the study period.
- Quantify humoral immune response via antibody titer.
Outcomes/Next steps: Findings were published in PLoS ONE in 2011.
MSP2-C1/ISA 720 was found to be immunogenic, with some parasite growth inhibition observed. Due to unexpected reactogenicity in subjects, the trial was halted after subjects received the 40 µg dose.
McCarthy JS, Marjason J, Elliott S, Fahey P, Bang G, et al. A phase 1 trial of MSP2-C1, a blood-stage malaria vaccine containing 2 isoforms of MSP2 formulated with Montanide® ISA 720. PLoS ONE. 2011;6(9):e24413.