Researchers at a scientific meeting in Washington disclosed they may be a step closer to conquering life threatening peanut allergies using an experimental treatment. 

Dr. Wesley Burks, a Duke University pediatric allergist, who presented the results Sunday at a meeting of the American Academy of Asthma and Immunology, said that five children who had not been able to eat peanuts due to sever peanut allergies now appear to have lost their allergies. 

Working in a similar manner to allergy shots, the new therapy works on the principle that gradual exposure to increasing amounts of peanut flour builds up tolerance. The immune system, blood tests show, begins to ignore the peanut flour instead of attacking it. 

Peanut or tree nut allergies are said to affect 3 million Americans and the numbers are rising. Half of the 150 deaths caused by food allergies in the U.S. each year are due to peanut allergies. Only 20 % of the children with peanut allergies outgrow them and the rest have to just live with the problem which has had no cure in sight. 

The studies were conducted by a joint team of researchers from Duke University Medical Center and the Arkansas Children's Hospital Research Institute. In the study 33 children who had peanut allergies were started on the lowest dose of peanut flour they could without a reaction which in some cases was as little as the equivalent of 1/1,000th of a peanut. 

The children were given precisely measured daily doses for two weeks and they then returned for tests and two weeks of slightly larger doses to be mixed in food. This pattern was continued and nine out of the 33 subjects have been on maintenance for 2 ½ years of which five weathered a challenge in which they were asked to eat peanuts and were declared fit to stop treatment though they must eat peanuts everyday. 

Burks said that other studies have shown that "as long as you keep something in your diet, your tolerance stays." He however cautions that the procedure is still experimental and the research should not be imitated at home as the subjects are closely monitored for any adverse reaction. 

The researchers in another trial involving 10 children who were given a placebo or peanut flour also reported that after a year the children who were given the peanut flour were able to tolerate 13 peanuts while the placebo group could only tolerate one peanut. 

Stacie Jones of Arkansas Children's Hospital who is Burk's collaborator said, "Within the next five years, I think we're going to have some active therapy for food allergy."

Dr. Scott Sicherer of Mt. Sinai School of Medicine's Jaffe Food Allergy Institute and a medical adviser to the Food Allergy Initiative said, "How does it translate into what people can practically do in their lives? How much are they protected?"