'Game-changing' drug allows children with allergies to eat foods that would have killed them

A drug used to treat asthma could prevent thousands of life-threatening allergic reactions, allowing hundreds of thousands of children with allergies to safely eat triggering foods. A study has found the drug omalizumab can prevent reactions to not just accidental exposure, but full portions of 'unsafe' foods in a third of young patients.Typically sufferers are advised to avoid eating foods they are allergic to – even if they are on treatment to help them better tolerate small exposures. But even a small amount of cross-contamination can be enough to trigger a fatal reaction, known as anaphylaxis. This serious reaction causes the throat and tongue to swell, blocking the airway resulting in loss of consciousness and suffocation. Others can go into cardiac arrest.But researchers from Stanford Medicine have now found a way of reducing the likelihood of anaphylaxis, hopsitalisation and even death. They found that participants taking omalizumab were significantly less likely to suffer an allergic reaction than those treated with standard immunotherapy. The study, published in the journal JAMA Pediatrics, followed 117 participants, with an average age of seven. Peanut allergy affects one in 50 children – roughly 240,000 in the UK and one million in the USAll participants were allergic to peanuts and at least two other foods, including milk, eggs, wheat, cashews, hazelnuts and walnuts. Half were randomly assigned to receive eight weeks of omalizumab, followed by standard oral immunotherapy – which works by exposing patients to tiny amounts of foods that trigger their allergies to build up tolerance of the immune system. The remaining participants were given omalizumab for the full year, injected either fortnightly or monthly. Results showed over a third of those treated with omalizumab alone were able to tolerate 4g - roughly a teaspoon - or more of all three trigger foods at the end of treatment, compared to less than 20 per cent of those on immunotherapy. Researchers also found that for all three allergens, over 70 per cent of omalizumab-treated participants were able to tolerate accidental exposures – reducing the threat posed by cross-contamination. Just 40 per cent of those on standard immunotherapy were able to safely consume the same 'accidental' amount. At the highest level tested - equivalent to a full-serving of the food- a quarter of omalizumab patients were able to safely consume all three of their allergens. But the protection offered by the two treatments was most striking. A worrying 27 per cent of participants in the standard treatment went into anaphylaxis when exposed to an allergen, compared to just two per cent of those on the new drug. None of those in the omalizumab group suffered serious adverse reactions, compared to over 30 per cent of the standard treatment group - who required timely medical attention.The researchers concluded: 'This study is very encouraging because it shows that we have treatment choices for our patients that are safe and not too burdensome.' However, they conceded that the large difference in effectiveness could be due to the high drop out rate in the immunotherapy group. Currently, the drug is approved in the US for use to prevent allergic reactions, but there has been no such decision by the Medicines and Healthcare products Regulatory Authority (MHRA) in the UK. It works by binding to and deactivating allergy-causing molecules in the blood and on immune cells. Food allergies are on the rise, with the number of people affected in the UK doubling between 2008 and 2018. Globally, it is estimated some 220 million people experience allergic reactions to certain foods. Around two million in the UK have a food allergy, according to the Food Standards Agency.For most, this means a few mild symptoms including an itchy rash or stomach ache. But around a quarter go on to develop a life-threatening reaction: anaphylaxis. It comes as young people with peanut allergies were dealt a huge blow early this year, after it was announced the only drug to reduce the risk of fatal reactions was being pulled from chemist shelves. The drug – Palforzia – works by exposing sufferers to tiny amounts of clinical-grade peanut flour, effectively retraining the immune system to reduce the risk of a serious allergic reaction. But the manufacturer advised in January 2026 that no new patients should be started on the drug after April 1.