UPDATE 2-World’s first malaria vaccine works in major trial
* Risk of severe malaria cut by 47 pct* GSK CEO says company will make no money from vaccine* Shares in partner Agenus rise more than 40 pct
(Adds reaction Bill Gates and from UK development minister)By Kate Kelland and Ben HirschlerSEATTLE/LONDON, Oct 18 (Reuters) -An experimental vaccine
from GlaxoSmithKline halved the risk of African children
getting malaria in a major clinical trial, making it likely to
become the world’s first shot against the deadly disease.Final-stage trial data released on Tuesday showed it gave
protection against clinical and severe malaria in five- to
17-month-olds in Africa, where the mosquito-borne disease kills
hundreds of thousands of children a year.”These data bring us to the cusp of having the world’s
first malaria vaccine,” said Andrew Witty, chief executive of
the British drugmaker that developed the vaccine along with the
nonprofit PATH Malaria Vaccine Initiative (MVI).While hailing an unprecedented achievement, Witty, malaria
scientists and global health experts stressed that the vaccine,
known as RTS,S or Mosquirix, was no quick fix for eradicating
malaria. The new shot is less effective against the disease
than other vaccines are against common infections such as polio
and measles.”We would have wished that we could wipe it out, but I
think this is going to contribute to the control of malaria
rather than wiping it out,” Tsiri Agbenyega, a principal
investigator in the RTS,S trials in Ghana, told Reuters at a
Seattle, Washington, conference about the disease.Malaria is endemic in around 100 countries worldwide and
killed some 781,000 people in 2009, according to the World
Health Organisation.Control measures such as insecticide-treated bednets,
indoor spraying and use of combination anti-malaria drugs have
helped significantly cut the numbers of malaria cases and
deaths in recent years, but experts have said that an effective
vaccine is vital to complete the fight against the disease.The new data, presented at the Bill & Melinda Gates
Foundation’s Malaria Forum conference in Seattle and published
simultaneously in the New England Journal of Medicine, were the
first from a final-stage Phase III clinical trial conducted at
11 trial sites in seven countries across sub-Saharan Africa.The trial is still going on, but researchers who analysed
data from the first 6,000 children found that after 12 months
of follow-up, three doses of RTS,S reduced the risk of children
experiencing clinical malaria and severe malaria by 56 percent
and 47 percent, respectively.”We are very happy with the results. We have never been
closer to having a successful malaria vaccine,” said Christian
Loucq, director of PATH MVI, who was at the conference.Loucq said widespread use of insecticide-treated bednets in
the trial — by 75 percent of people taking part — showed that
RTS,S can provide significant protection on top of other
existing malaria control methods.Results in babies aged six to 12 weeks are expected in a
year’s time and, if all goes well, GSK believes the vaccine
could reach the market in 2015.COSTSGetting RTS,S to African infants who need it will take a
concerted effort from international funders such as the Gates
Foundation, which helped pay for the research. Health experts
have said it must be cheap enough to be cost-effective.Gates said the results were a “huge milestone” in the fight
against malaria.Witty declined to say if a course of three shots would cost
under $10 but told reporters RTS,S would be priced as low as
possible. The company has previously said it would charge only
the cost of manufacturing it plus a 5 percent mark-up, which
would be reinvested into tropical disease research. “We are not
going to make any money from this project,” Witty said.However, shares in GSK’s small U.S. biotech partner Agenus,
which makes a component of the vaccine, rose more than 40
percent after news of the clinical trial result.Britain’s minister for international development Andrew
Mitchell said the vaccine “offers real hope for the future.”“An effective, long-lasting and cost-effective vaccine
would make a major contribution to malaria control,” he told
the conference.Malaria is caused by a parasite carried in the saliva of
mosquitoes. The RTS,S vaccine is designed to kick in when the
parasite enters the human bloodstream after a mosquito bite. By
stimulating an immune response, it can prevent the parasite
from maturing and multiplying in the liver.Without that immune response, the parasite gets back into
the bloodstream and infects red blood cells, leading to fever,
body aches and in some cases death.RTS,S’s co-inventor Joe Cohen said the data were robust and
consistent with earlier trials, which also showed around 50
percent efficacy. Side effects, including fever and
injection-site swelling, were similar in children given RTS,S
and a control vaccine.After working for 24 years on developing the shot, he said
he was “very proud of what we have achieved.”Some external commentators were cautious about the
vaccine’s potential, but said it was an important development
that should save many lives. Health experts normally like to
see a success rate of 80 percent plus in a vaccine.”We’re probably not there yet, but this is a really
important advance in science,” Peter Agre, director of the John
Hopkins Malaria Research Institute and a former Nobel prize
winner, told Reuters at the conference.In an editorial in the New England Journal of Medicine,
Nicholas White of Thailand’s Mahidol University said, “It is
becoming increasingly clear that we really do have the first
effective vaccine against a parasitic disease in humans.”
