Circassia Ltd, a specialty biopharmaceutical company focused on allergy, announced the results of a phase II clinical trial showing that patients who received four doses of its ToleroMune cat allergy vaccine over a 12-week period maintained a statistically significant reduction in symptoms one year later. The results of the study were presented in the opening Plenary Symposium of the European Academy of Allergy and Clinical Immunology Congress on Sunday June 12 by Professor Mark Larché, Canada Research Chair in Allergy and Immune Tolerance at McMaster University, Canada.

The study followed an earlier randomised double-blind phase II trial in 202 cat allergy patients, in which those who received four doses of Circassia's T-cell vaccine over 12 weeks had a significantly greater improvement in their symptoms than those on placebo. The treatment was extremely well tolerated.

The new results show that one year after the start of the original study, the treated group's tolerance to cat allergens was maintained, and had continued to improve substantially following the completion of the treatment, despite the patients receiving no booster doses. As a result, immediately following treatment, the patients had experienced a 94% improvement in their total rhinitis symptoms compared with placebo. By the end of the 12-month study, the ToleroMune T-cell vaccine had reduced the same patients' symptoms by 133% more than placebo (p=0.01). This treatment effect is 2.6 - 4.3 times that achieved by several currently approved allergy therapies in key clinical trials.

Commenting on the study results, Professor Mark Larché, Canada Research Chair in Allergy and Immune Tolerance, McMaster University, said, “Maintaining such a significant level of symptom improvement over an extended period is a major step forward. Achieving this with a course of just four doses is unprecedented, and represents an important breakthrough that has the potential to lead to improved treatments for allergy sufferers worldwide.”

“We are extremely excited by these new clinical results, which again demonstrate the potential of our ToleroMune technology to revolutionise allergy treatment,” said Steve Harris, Circassia's CEO. “These results, achieved with our commercial room-temperature-stable formulation, clearly show that Circassia's T-cell vaccines offer the prospect of major clinical and manufacturing benefits over traditional immunotherapies. We intend to capitalise on these impressive results as quickly as possible, and having recently completed one of the largest private fundraisings in the history of European biotechnology, plan to advance our cat allergy treatment into phase III testing in 2012.”