A trial aimed at helping children overcome their peanut allergy has produced “very promising results”, US researchers say.
Experts found youngsters could build up their tolerance to peanuts if they were given daily drops of peanut protein under the tongue.
It is the first time scientists have used peanut drops, which they say have fewer side effects than the peanut flour used in other studies.
About one in 50 youngsters in the UK suffers a peanut allergy, which can cause breathing problems and, in severe cases, a potentially fatal reaction called anaphylaxis.
For the latest research, experts in Massachusetts and North Carolina recruited 18 children aged between one and 11.
Eleven of the children were given daily drops containing increasing doses of peanut protein while seven children were given dummy drops.
The results showed that, after one year, those children on the peanut drops had built up their tolerance until they were consuming the equivalent of five to 10 peanuts a day.
Meanwhile, those on placebo drops were unable to tolerate even one peanut.
Edwin Kim, an immunologist at Duke University Hospital in North Carolina, who led the study, said: “When children are given peanut flour they get a significantly higher dose than for peanut drops – around 100 times higher dose.
“Children also have an aversion to the smell and texture of peanut flour, and side effects can include abdominal pains.
“Drops have the potential to be a safer route of administration and they are easy to give to children.
“We have seen very promising results from this trial.
“Even after one year there is a clear difference between children on the drops compared with those on placebo.”
Some children on the trial are now coming up to their third year of taking daily drops, with no major problems.
Side effects have included itching in the mouth five to 10 minutes after taking the drops, and one child required antihistamine.
Dr Kim’s team hope they will be able to reduce the number of drops children need to perhaps a weekly dose.
“This is a very safe and a very easy treatment,” he said.
“I wouldn’t go as far as to say this is a cure but we are getting closer.
“If you combine what we have learned from peanut flour and these drops, I think we are knocking on the door.
“We know that we can manipulate the immune system. We are learning lots about how the allergy works.”
The results of the first year of the trial will be presented at the British Society for Allergy and Clinical Immunology conference in Nottingham this week.
Last year, doctors in Cambridge conducted a larger trial using flour.
More than 100 children were given increasing doses of peanut flour, up to the equivalent of five nuts a day.
Glenis Scadding, president of the British Society for Allergy and Clinical Immunology, said “A cure for their peanut allergy is something most peanut allergy sufferers long for.
“It is known that desensitisation using gradually increasing doses of peanut can result in tolerance, but concerns about the risk of allergic reactions during treatment mean that this is not yet something available in routine allergy practice.
“This study looks at a new method of peanut desensitisation using small doses of peanut allergen under the tongue.
“This preliminary data shows very promising results for a safe and effective method of peanut desensitisation.”