Researchers in the US have made a critical step in better treating very young children with peanut allergy through the use of immunotherapy.

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

Of the 40 participants allergic to peanuts aged 9 to 36 months, nearly 80 per cent incorporated foods containing peanuts into their diets after receiving peanut oral immunotherapy (OIT).

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

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

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

Each participant was assigned either high-dose peanut OIT with a target daily dose of 3000 milligrams peanut protein or a low-dose regimen with a target dose of 300 milligrams.

Low-dose and high-dose OIT 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 OIT for 29 months on average, participants avoided peanut completely for four weeks before attempting to reintroduce it into their diets.

Previous studies with older children showed peanut OIT can offer some protection against potentially life-threatening anaphylaxis caused by peanut exposure.

The investigators at University of North Carolina are continuing to monitor the OIT-treated participants to assess the long-term treatment outcomes.

Australia has a relatively high prevalence of peanut allergy, affecting almost three in every 100 children.

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

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