The Latest Reaction to Allergy 'Vaccine'
The Swiss company Cytos has carried out large scale tests on an allergy vaccine that might help the millions of people who suffer from conditions such as hayfever, asthma and even life-threatening anaphylactic reactions.
Allergies are thought to affect about one person in every five and current approaches to treatment usually involve controlling the symptoms with drugs like antihistamines, or suppressing the immune system using agents such as steroids. Immunotherapy can also be used. This involves injecting the allergic person with increasing levels of an allergen (the thing they are allergic to, such as grass pollen or pet hair) to hyposensitize them (make them less sensitive). However, the results have been mixed, and this approach can be very dangerous for people with serious allergies as exposure to even tiny amounts of allergen trigger a fatal reaction. As a result, those who would benefit most from an allergy vaccine have not been able to have one.
Now Cytos think they may have the answer - a vaccine that works by fooling the body into thinking it is under attack from a bacterial infection. This activates the arm of the immune system linked to fighting off disease and leads to the suppression of the immune pathways responsible for allergies.
Two tests were carried out. In one, 80 people with pet or dust mite allergies were injected with six increasing doses of the vaccine or with a placebo. In the other, injection of the vaccine plus allergen extract was compared with allergen extract alone in 93 patients. The tests showed that the vaccine on its own was more effective at reducing allergy symptoms than when combined with an allergen, as well as having ten times fewer adverse reactions and also that the vaccine was twice as effective as a placebo.
As well as not having to worry about reactions to allergens in the vaccine, another benefit is that the same vaccine can be used against many different allergic conditions, be that hay fever, nut allergies, asthma or reactions to pet fur. Cytos plan to start further larger trials before the end of 2008 to test how well the vaccine works at each dose.