An asthma drug has been shown to reduce the risk of severe reactions in people with food allergies. The evidence emerges from a study (Wood, Togias et al., 2024) published in the New England Journal of Medicine. (1)
A drug against food allergies
Researchers tested the drug omalizumab, indicated for the treatment of asthma, on 180 subjects - 3 adults and 177 children aged between one and 17 years - severely allergic to peanuts and at least two other foods including cashews, milk, eggs, tree nuts , wheat and hazelnuts.
Inclusion in the study randomized (drug versus placebo) required participants to have an allergic reaction to a test food containing 100 mg or less of peanut protein and 300 mg or less of two other allergens.
The result
During the experimentation, participants received a dose of omalizumab or placebo administered subcutaneously (with the dose based on weight and IgE levels) every 2 to 4 weeks.
After about four months of treatment, 67% of participants treated with the drug ingested the equivalent of two or three peanuts without experiencing a significant allergic reaction, compared to 7% of those who received a placebo.
The administration of the drug also increased participants' tolerance to other reported allergens.
'In subjects as young as 1 year of age with multiple food allergies, treatment with omalizumab for 16 weeks was superior to placebo in increasing the reaction threshold for peanuts and other common food allergens'explain the researchers.
Nature's analysis
The Food and Drug Administration (US FDA), based on these results, has approved omalizumab as a treatment for food allergies starting from March 2024, reports Nature, which comments on the discovery in an article. (2)
The drug used in the trial (omalizumab) is an anti-IgE monoclonal antibody that has been in use for over twenty years. The FDA approved it (Xolair is the brand name in the United States) in 2003 for the treatment of asthma in 2003 and, later, for chronic urticaria and nasal polyps.
The limits of the drug against food allergies
The drug is considered safe, without side effects, even on children. However, its approval as an 'attenuator' of allergic reactions is not without contraindications. Omalizumab, in fact:
– involves a general lowering of IgE, antibodies that are activated in the presence of proteins recognized as threats. However, in the case of allergen proteins (peanuts etc.), they trigger unnecessary inflammation which can generate anaphylactic shock. Hence the usefulness of 'turning off' the immune reaction.
Omalizumab recognizes all types of IgE antibodies, including those that attack air pollutants (cause of asthma) and food proteins. Precisely because of this wide range of action, it is assumed that it can also act against pollen allergy and eczema. On the other hand, there is a fear that lowering the natural defenses of IgE antibodies could make the body more vulnerable to infections,
– allergic reactions are attenuated but not eliminated. Treated people may develop a (false) belief that they have eliminated the problem, while the drug can only increase the amount of allergen tolerated. Furthermore, it is not clear whether the drug is able to reduce the severity of the allergic reaction by consuming, for example, a handful of peanuts,
– the molecule does not work on everyone. 14% of study participants treated with omalizumab were still unable to consume even a single piece of peanut without having an allergic reaction,
– the cost of treatment is high. In the United States it costs 1.400 dollars per injection.
Alternatives to omalizumab
In addition to omalizumab, FDA approved the only other available peanut allergy treatment in 2020. Palforzia is a peanut protein powder suitable for allergic children aged four years and older. It is administered in increasing doses over six months to allow the immune system to develop a tolerance to peanuts over time.
Meanwhile, the search continues. Two other treatments are being tested:
– another monoclonal antibody (dupilumab), approved for the treatment of asthma and eczema, is being tested in people with peanut allergies. The drug targets signaling molecules, released by immune cells, that trigger inflammation,
– an eczema drug (abrocitinib), which blocks certain types of signaling pathways in immune cells, is being tested to treat several types of food allergies.
Other researchers are evaluating 'more simply' whether giving four-month-old babies small amounts of eight common allergens such as wheat and shellfish can prevent the development of allergies.
Marta Strinati
Footnotes
(1) Robert A. Wood, MD, Alkis Togias, MD, Scott H. Sicherer, MD, Wayne G. Shreffler, MD, Ph.D., Edwin H. Kim, MD, Stacie M. Jones, MD, Donald YM Leung, MD, Ph.D., Brian P. Vickery, MD, J. Andrew Bird, MD, Jonathan M. Spergel, MD, Ph.D., Ahmar Iqbal, MD, MBA, Julie Olsson, MD Omalizumab for the Treatment of Multiple Food Allergies. New England Journal of Medicine. February 25, 2024. https://doi.org/10.1056/NEJMoa2312382
(2) Sara Reardon. 'Breakthrough' allergy drug: injection protects against severe food reactions. Nature. 26.2.24 https://www.nature.com/articles/d41586-024-00586-8
A professional journalist since January 1995, she has worked for newspapers (Il Messaggero, Paese Sera, La Stampa) and periodicals (NumeroUno, Il Salvagente). She is the author of journalistic studies on food and has published the book "Reading labels to know what we eat".
