A phase I/IIa safety, immunogenicity, and efficacy bridging randomized study of a two-dose regimen of liquid and lyophilized formulations of the candidate malaria vaccine RTS,S/AS02A in malaria-naïve adults.

We conducted an open-label safety and immunogenicity bridging study that compared liquid and lyophilized formulations of the candidate malaria vaccine RTS,S formulated in AS02A in 34 healthy, malaria-naïve adults at WRAIR. Volunteers received two doses of either formulation on a 0, 1-month schedule. Both vaccines were well tolerated and similarly immunogenic.