Final results of a study show that the world's leading malaria vaccine candidate appears to be a disappointment. The study showed that it doesn't work very well and that initial protection fades over time.
Despite the poor results - it protects about one-third of children vaccinated - developers are moving ahead to get it approved because it could still help protect some children from getting the mosquito-spread disease.
The pharmaceutical company GlaxoSmithKline has spent hundreds of millions of dollars on the vaccine, with additional backing from the non-profit group PATH Malaria Vaccine Initiative and funds from the Bill and Melinda Gates Foundation. The vaccine is likely to be the world's first licensed shot for malaria. A decision from the European Medicines Agency is expected later this year.
The World Health Organization had set a target of 2015 for having a malaria vaccine that was at least 50 percent effective with protection lasting longer than a year.
According to a study published Friday in the British journal The Lancet, those goals have been missed with the GlaxoSmithKline vaccine, although scientists say the shot isn't a complete waste.
"Everyone accepts that this is not the perfect or the last malaria vaccine," said Brian Greenwood of the London School of Hygiene and Tropical Medicine, the study's lead author. "It's not good enough to stop transmission but it will cut the huge burden of disease."
Seven African countries involved in study
The vaccine study involved about 15,500 babies and toddlers in seven African countries. One group got three doses; a second group also got a booster shot and a third group got dummy shots. All of the children used a mosquito bed net and they were followed for up to four years.
Overall, the vaccine was about 30 percent effective in those who got three doses and a booster shot but the protection waned over time.
The WHO said it expects to make a recommendation about the vaccine in October if the European Medicines Agency has issued its assessment by then.
av/bk (AP, Reuters)