Researchers in the US have created a vaccine they believe will help treat multiple allergies.
The jab contains a cocktail of allergy-causing compounds and is administered in several increasing doses over eight weeks. The theory is that by gradually upping the amount of these triggers in a controlled way (a treatment known as immunotherapy), the immune system becomes more tolerant to them, which eradicates symptoms and provides long-term protection against other allergies.
About one in five people has allergic rhinitis, a reaction to triggers, also called allergens, such as dust or animal dander. Allergens contain proteins that can trigger the production of histamine, a chemical in the body that causes cold-like symptoms. Immunotherapy can be given to those with severe allergies (typically to pollen) to try to make the immune system less reactive.
The conventional treatment involves being given small doses of one allergen. However, this works only for one allergy and needs to be given at three-monthly intervals for years.
But in the new trial, doctors are using a cocktail of six different allergens and it is hoped that the effects of the new jab will be lifelong.
In the trial, at Johns Hopkins University in the US, 36 patients will be given increasing doses of the jab (named Allergen Immunotherapy Extract) or a placebo, twice a week for eight weeks.
Commenting on the study, Christopher Corrigan, a professor of asthma, allergy and immunology at King’s College, said: “Treating people with a cocktail of allergens sounds like a good idea to combat multiple allergies.
“But in practice, treating with an arbitrary mixture of allergens may mean inadequate treatment for key allergens that are causing symptoms and unnecessary treatment for others, which are not causing symptoms.”