Scientists across Africa are celebrating the news that the world's first vaccine against malaria has been approved by the European Medicines Agency.
The vaccine, named Mosquirix, was given the green light on Friday after more than 30 years of research, detailed in 230,000 pages of data. It now means that the vaccine will be examined by the World Health Organisation and, if approved, could be administered to children across Africa within the next few years.
"It's massively significant," said Allan Pamba, vice president for pharmaceuticals in East Africa for GlaxoSmithKline (GSK), which has spent more than $356 million (£230m) to date on finding a vaccine. GSK expects to invest a further $200 to $250 million until development is completed.
In January 2001, GSK and PATH Malaria Vaccine Initiative, with grant monies from the Bill & Melinda Gates Foundation to PATH, entered into a public-private partnership to develop a vaccine. PATH has invested more than $200 million, much of it from the Gateses.
"Malaria has been incredibly difficult to crack. It's been tremendously frustrating. But we are all immensely proud to have reached this milestone."
The WHO has said it may give a policy recommendation by the end of the year; African authorities will then take their decisions about how and where they would implement a vaccination programme.
But, given that an estimated 600,000 people die from malaria every year - 90 per cent in sub-Saharan Africa - Dr Pamba said the health ministers he spoke to on a regular basis were eagerly awaiting the arrival of a vaccine.
"Pretty much every health minister I speak to has had malaria," said Dr Pamba, who was born in Kenya and now works between Nairobi and London. "They all want to know when it will be ready."
Mosquirix, whose scientific name is "RTS,S" has been designed to prevent malaria caused by the Plasmodium falciparum parasite, which is most prevalent in sub-Saharan Africa. It is the first vaccine to be developed which counters the effects of a parasite.
The vaccine is designed to prevent the parasite from infecting, maturing and multiplying in the liver, after which time the parasite would re-enter the bloodstream and infect red blood cells, leading to disease symptoms.
The developers carried out a trial programme involving more than 16,000 young children, conducted by 13 African research centres in eight African countries - Burkina Faso, Gabon, Ghana, Kenya, Malawi, Mozambique, Nigeria, and Tanzania.
Two groups of children were tested: infants aged from six to 12 weeks, and young children aged five to 17 months.
Data from the trial programme demonstrate that over the first 18 months following three doses of RTS,S, malaria cases were reduced by almost half in the older group. With infants, cases dropped by 27 per cent.
Sir Andrew Witty, CEO of GSK, said: "Today's scientific opinion represents a further important step towards making available for young children the world's first malaria vaccine.
"While RTS,S on its own is not the complete answer to malaria, its use alongside those interventions currently available such as bed nets and insecticides, would provide a very meaningful contribution to controlling the impact of malaria on children in those African communities that need it the most."