Circassia Ltd, a specialty biopharmaceutical company focused on controlling immune system responses, announced positive results from a phase-II clinical study of its anti-allergy technology, ToleroMune, in the field of cat allergy. The trial showed that ToleroMune treatment can substantially reduce allergic reactions to the allergen that causes most cat allergies, and importantly was well tolerated by all patients.
Circassia conducted the double-blind study in Germany, where patients with a confirmed history of cat allergies received a single dose of ToleroMune therapy or placebo. The 88 study participants were divided into groups, with each receiving a different dose, either via subcutaneous or intradermal injection to compare the two routes of administration. To test the effect of the treatment, patients received a microscopic dose of cat dander (the main allergen responsible for cat allergies) into their skin several weeks later.
Patients who received ToleroMune therapy via the most effective administration route had markedly reduced skin reactions to the cat allergen at all the five dose levels tested compared with placebo. The most effective dose reduced reactions by over 40 per cent, compared with 10 per cent for placebo. Throughout the study the ToleroMune treatment proved well tolerated, with no serious or severe adverse events experienced in any of the groups, despite the steadily increasing doses.
"These results are extremely encouraging, both for Circassia and the huge number of people who suffer from allergies. Current treatment options address the symptoms only or require repeated administrations over many months under specialist supervision because of the potential for serious and even life-threatening side effects, which is a particularly important issue for cat allergy therapies. Therefore, achieving a marked reduction in allergic responses after just a single dose is remarkable, and we aim to build on this by testing short treatments of several doses in future trials," said Steve Harris, Circassia's CEO.
"Our goal for ToleroMune is to provide a range of allergy therapies that effectively and quickly treat the underlying disease while also offering excellent safety. Consequently, these positive clinical results will not only contribute to the development of our cat allergy product, but will also provide the foundations for our other allergy programmes that utilize our ToleroMune technology," Harris added.
In addition to their potential clinical benefits, Circassia's anti-allergy products would have significant market opportunities. Currently, over 150 million people suffer from allergic rhinitis in the US and Europe and the market for current treatments, despite their limitations, is approximately $12 billion per year. The prevalence of cat-dander allergy is high, with 1-in-6 Americans and nearly 10 per cent of Europeans suffering from the condition.
Existing treatments have a number of issues, either providing symptomatic relief only or requiring lengthy supervision by specialist physicians. In contrast, Circassia's ToleroMune technology has the potential to rapidly desensitize sufferers using extremely small sections of allergens (termed T-cell epitopes), which minimizes the potential for adverse reactions.