A Phase 1, First-in-human, Double-blinded, Randomized, Placebo-controlled Trial of a Zika Virus Purified Inactivated Vaccine (ZPIV) With Alum Adjuvant in Healthy Flavivirus-naive and Flavivirus-Primed Subjects.

Abstract

Phase 1 study to evaluate two doses of Alum Adjuvanted Zika Virus Purified Inactivated Vaccine (ZPIV) administered 28 days apart. The study will enroll 75 flavivirus naïve healthy adult subjects into 3 equal groups sequentially. Each group will include 20 ZPIV recipients and 5 placebo recipients. Group 1 will receive two ZPIV or placebo doses 28 days apart. Those in Group 1 who consent to a third ZPIV dose will receive 5.0 mcg dose of ZPIV or placebo administered IM on Day 224. Group 2 subjects will receive a two-dose regimen of IXIARO® 28 days apart; two ZPIV or placebo doses three months later 28 days apart. Those in Group 2 who consent to a third ZPIV dose will receive it on Day 336. Group 3 subjects will receive one dose of YF-VAX® followed three months later by two ZPIV or placebo doses 28 days apart. Those in Group 3 who consent to a third ZPIV dose will receive it on Day 308. In each group, those who do not agree to receive the third ZPIV dose will be followed based on the schedule. The primary objectives are: 1) To evaluate the safety and reactogenicity of a two-dose homologous prime-boost regimen of ZPIV among flavivirus-naïve, YF-VAX® primed, and IXIARO® primed subjects; 2) To evaluate the safety and reactogenicity of a third dose of ZPIV in consenting subjects.