Malaria vaccines RTS,S/AS01 and R21/Matrix-M reduce malaria risk in children
This systematic review and meta-analysis included 8 eligible studies from a screening of 832 records, evaluating the RTS,S/AS01 and R21/Matrix-M malaria vaccines in children aged 6-12 weeks and 5-17 months. The primary outcome was malaria risk reduction and efficacy, with secondary outcomes including immunogenicity.
In the 6-12-week age group, RTS,S/AS01 provided significant protection with a malaria risk reduction of 23.0% (risk ratio [RR] = 0.77). In the 5-17-month age group, both vaccines demonstrated a malaria risk reduction with RR = 0.61. However, efficacy declined over time, highlighting the importance of a booster dose.
Both vaccines generated strong antibody responses in the 5-17-month age group. RTS,S/AS01 was reported as safe across age groups. The R21 vaccine showed high efficacy with a low event rate of 0.22 and strong antibody response, but was associated with more frequent adverse events.
The review did not report specific limitations, funding, or conflicts of interest. The findings support the use of these vaccines in young children, though clinicians should be aware of the need for booster doses and the higher adverse event rate with R21.