This Phase 1 study, conducted in malaria-naïve adults in Australia, was designed to determine the safety, reactogenicity, and immunogenicity of the apical membrane antigen 1-combination 1 (AMA1-C1) vaccine, formulated with the water-in-oil adjuvant ISA 720.
Volunteers were divided into three dose-escalating groups (5 µg, 12 µg, and 80 µg), and received multiple intramuscular vaccinations of AMA1-C1 adjuvanted in ISA 720 on a 0,84,168-day schedule.
The study was designed with two objectives:
- Assess the safety and reactogenicity of the AMA1-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 Vaccine in 2010.
AMA1-C1/ISA 720 was found to be immunogenic, however; antibody responses were relatively short-lived. Although the vaccine was reasonably tolerated, some transient, severe, local reactions were observed in subjects.
Pierce MA, Ellis RD, Martin LB, Malkin E, Tierney E, et al. Phase 1 safety and immunogenicity trial of the Plasmodium falciparum blood-stage malaria vaccine AMA1-C1/ISA 720 in Australian adults. Vaccine. 2010;28(10):2236-2242.