An experimental malaria vaccine given to African infants younger than 12 weeks reduced the risks of clinical and severe malaria only by about one-third, reports an international team of researchers (The RTS,S Clinical Trials Partnership. N Engl J Med. doi: 10.1056/NEJMoa1208394 [published online November 9, 2012]).
In the phase 3 trial, 6537 infants who were between 6 and 12 months old at the time of the first vaccination received 3 doses of either the RTS,S/AS01 candidate vaccine or a nonmalaria comparator vaccine at 1-month intervals along with standard childhood vaccines. An analysis of the incidence of malaria in infants for 12 months after the third vaccine dose found that the RTS,S/AS01 vaccine reduced the risk of detectable malaria and severe malaria by 31% and 37%, respectively, compared with controls.
Friedrich MJ. Experimental Malaria Vaccine. JAMA. 2012;308(23):2449. doi:10.1001/jama.2012.128613