Initial phase III results at 18 months showed vaccine efficacy of about 46 percent
The world's first malaria vaccine may be available by October, as the vaccine candidate (RTS,S/AS01) is the first to reach phase III clinical testing and is partially effective against the clinical disease in young African children up to four years after vaccination.
The RTS,S/AS01 vaccine was developed for use in sub-Saharan Africa where malaria still kills around 1,300 children every day. There is currently no licensed vaccine against malaria anywhere in the world.
The final trial data is published in The Lancet journal.
The results suggest that the vaccine could prevent a substantial number of cases of clinical malaria, especially in areas of high transmission. Protection was prolonged by a booster dose, increasing the average number of cases prevented in both children and young infants.
"Despite falling efficacy over time, there is still a clear benefit from RTS,S/AS01. An average 1,363 cases of clinical malaria were prevented over 4 years of follow-up for every 1,000 children vaccinated, and 1,774 cases in those who also received a booster shot. Over 3 years of follow-up, an average 558 cases were averted for every 1,000 infants vaccinated, and 983 cases in those also given a booster dose," said Mr Brian Greenwood, corresponding author and Professor of Clinical Tropical Medicine at London School of Hygiene and Tropical Medicine in the UK, in a statement.