Immunotherapy has successfully treated babies with peanut allergy in a clinical trial conducted by researchers in the United States.

Of the 40 participants allergic to peanuts aged between nine and 36 months, nearly 80% incorporated foods containing peanuts into their diets after receiving peanut oral immunotherapy.

“This study provides critical evidence supporting the safety and effectiveness of peanut oral immunotherapy in treating young children newly diagnosed with peanut allergy,” said Marshall Plaut, from the National Institute of Allergy and Infectious Diseases.

Encouragingly, low-dose therapy was effective at suppressing allergic responses, Plaut said.

Peanut oral immunotherapy involves eating small, gradually increasing amounts of peanut protein daily.

Each participant was assigned either high-dose peanut oral immunotherapy with a target daily dose of 3,000 milligrams of peanut protein or a low-dose regimen with a target dose of 300 milligrams.

Low-dose and high-dose oral immunotherapy were safe and equally effective at suppressing allergic immune responses to peanut, investigators found.

Nearly all participants experienced some side effects, such as abdominal pain, but these were generally mild and required little or no treatment.

After receiving oral immunotherapy for 29 months on average, participants avoided peanut completely for four weeks before attempting to try it again.

Previous studies with older children showed the therapy could offer some protection against potentially life-threatening anaphylaxis.

The investigators at University of North Carolina will monitor the oral immunotherapy-treated participants to assess the long-term treatment outcomes.

Australia has a relatively high prevalence of peanut allergy: almost three in every 100 children are affected.

The most severe symptom of a peanut allergy is anaphylaxis, which can become life-threatening if not treated promptly.

The findings have been published in the Journal of Allergy and Clinical Immunology.