Phase I Study of AMA1-C1/Alhydrogel® (Registered Trademark) + CPG 7909 Malaria Vaccine

AMA1-C1 + CPG 7909 is a blood stage malaria vaccine candidate. The objectives of this Phase 1 study are to confirm the previously demonstrated safety and immunogenicity of AMA1-C1 + CPG 7909 formulated in a phosphate buffer. In addition, this study will evaluate the safety and immunogenicity of AMA1-C1 + CPG 7909 formulated in a saline buffer, and determine if the addition of CPG 7909 in a saline buffer enhances the immune response to AMA1-C1 in a manner similar to that seen with the addition of CPG 7909 in a phosphate buffer. The immunological effect of giving a second dose of vaccine at 1 or 2 months will also be evaluated. The study is a double blind Phase 1 clinical trial in healthy adult volunteers. Volunteers will be screened and 24 participants will be enrolled and randomly assigned to 1 of 4 groups in a 2x2 design: 6 volunteers will receive 2 doses of 80 micrograms AMA1-C1/Alhydrogel + 500 micrograms CPG 7909 (phosphate) at a 1-month dosing interval; 6 volunteers will receive 2 doses of 80 micrograms AMA1-C1/Alhydrogel + 500 micrograms CPG 7909 (saline) at a 1 month dosing interval; 6 volunteers will receive 2 doses of 80 micrograms AMA1-C1/Alhydrogel + 500 micrograms CPG 7909 (phosphate) at a 2-month dosing interval; and 6 volunteers will receive 2 doses of 80 micrograms AMA1-C1/Alhydrogel + 500 micrograms CPG 7909 (saline) at a 2 month dosing interval. Safety outcome measures are local and systemic (including laboratory) adverse events. Immune responses to vaccination will be measured by enzyme-linked immunosorbent assay (ELISA) and parasite growth inhibition assay (GIA), and will be compared among groups.