Successful peanut immunotherapy trial

Following on from the report on the successful US trial of immunotherapy for cow’s milk allergy, researchers at Addenbrooke’s Hospital in Cambridge have now successfully desensitised a small group of peanut allergic children to peanuts – although they warn that people with peanut allergy should not try to desensitise themselves or a child at home because there is a real risk that a person will react and need emergency treatment, as did one child in the early stages of this trial.

The Cambridge researchers examined four peanut-allergic children to establish the dose of peanut protein that would be enough to cause a reaction. The children then had daily single-dose treatments of peanut flour with the dose increasing by a small amount twice a week. The first dose contained 5 mg of peanut protein and the final dose contained 800 mg. After six weeks of treatment they were reassessed to see whether their dose threshold had changed, and then they continued with the daily treatment.

The first assessment showed the children had dose thresholds ranging from 5 to 50 mg (between one-fourtieth and a quarter of a peanut). One child reacted with anaphylaxis during the assessment and had to have an adrenaline injection.

All the children tolerated the increasing dosage up to the 800 mg peanut protein level and none needed an adrenaline injection.

Each child was able to tolerate at least 10 whole peanuts (about 2.38 grams of protein) at his or her threshold re-assessment. This means the threshold went up at least 48, 49, 55 and 478-fold for the four children respectively.

This is certainly enough to protect a child against accidental contact with a peanut and even holds out the hope of an eventual cure.

Successful oral tolerance induction in severe peanut allergy. AT Clark, S Islam, Y King, J Deighton, K Anagnostou, PW Ewan. Allergy Published Online: Feb 17 2009. DOI: 10.1111/j.1398-.2009.01982.x

First published in April 2009

Click here for more research reports

Top of page