Long-term safety and efficacy of the RTS,S/AS02A malaria vaccine in mozambican children

Abstract

Background. We previously reported that the RTS,S/AS02A vaccine had an acceptable safety profile, was immunogenic, and demonstrated efficacy against Plasmodium falciparum malaria disease for 21 months. Methods. We conducted a randomized, controlled, phase 2b trial of RTS,S/AS02A in 2022 Mozambican children aged 1-4 years. We now report safety results for all randomized subjects and vaccine efficacy (VE) findings for children in the Manhiça area over the 45-month surveillance period. Results. During the surveillance period, the VE(2.5-45) (VE over months 2.5-45 of surveillance) against a first or only episode of clinical malaria disease was 30.5% (95% confidence interval [CI], 18.9%-40.4%; P< .001), and the VE (2.5-45) against all episodes was 25.6% (95% CI, 11.9%-37.1%;