RTS,S/AS01 vaccination effectiveness against malaria was demonstrated in a phase III, double-blind, randomized, controlled study in Sub-Saharan Africa. Researchers are currently presenting detailed safety findings from this investigation. 8922 children and 6537 newborns were randomly assigned to receive four doses of RTS,S/AS01 or a non-malaria control vaccination, or three doses of RTS,S/AS01 plus a control vaccine. A multi-functional team evaluated aggregate safety data. Severe malaria with a Blantyre Coma Score of 2 was evaluated post-hoc, as was gender-specific mortality. Throughout the research, the rates of serious adverse events (SAE) and fatal SAEs were 24.2 percent–28.4 percent and 1.5 percent–2.5 percent, respectively, across groups; 0.0 percent–0.3 percent of individuals reported vaccination-related SAEs. The prevalence of febrile convulsions in children was greater within the first 2–3 days following RTS,S/AS01 vaccination than with the control vaccine, which corresponded to the temporal frame of post-vaccination febrile responses in our investigation. Meningitis cases in children had a statistically significant numerical imbalance, but not in babies. Cases of CM were more common in children who had received RTS,S/AS01 vaccinations, but not in newborns. In this study, RTS,S/AS01-vaccinated girls had greater all-cause mortality than control girls, despite the fact that overall mortality was low.

The reported meningitis and CM signals are seen to be plausible chance results that, given their severity, need additional investigation in phase IV trials and WHO-led pilot implementation programs to define the RTS,S/AS01 benefit-risk profile in real-life situations.

Reference: https://www.tandfonline.com/doi/full/10.1080/21645515.2019.1586040