Last updated on April 21, 2014 at 5:04 EDT

Circassia’s Ragweed Allergy Therapy Achieves Positive Phase II Clinical Results

March 8, 2012

OXFORD, England, March 8, 2012 /PRNewswire/ –

Circassia Ltd, a specialty biopharmaceutical company focused on allergy, today
announced that its ragweed allergy therapy has achieved positive results in a key phase II
clinical trial. In the study, patients with more severe symptoms achieved a significantly
greater improvement following treatment with the ToleroMune(R) T-cell vaccine than those
on placebo (pless than or equal to0.05). The results were presented at the 2012 Annual
Meeting of the American Academy of Allergy, Asthma and Immunology*.

“The results of this key phase II study are highly encouraging, because they show our
ToleroMune ragweed allergy vaccine can reduce patients’ symptoms after just a short course
of treatment and, most importantly, offers the greatest improvement to those who can
benefit most,” said Steve Harris, Circassia’s CEO. “We have now achieved successful phase
II results with four of our allergy T-cell vaccines, which validate our scientific
approach and give us the confidence to progress our lead programmes into the final phase
of development.”

Circassia’s latest phase II study was designed to assess the T-cell vaccine’s efficacy
and tolerability and to identify the optimal treatment regime. The trial was conducted in
Canada in 275 ragweed allergy patients. During the randomised, double-blind,
placebo-controlled trial, volunteers received one of four regimens of ToleroMune treatment
over a three-month period. Patients were exposed to ragweed allergens in a validated
exposure chamber, and investigators compared their nasal and ocular symptoms against the
pre-treatment baseline. The results show that the T-cell vaccine’s optimal regimen
substantially reduced patients’ symptoms, achieving a 97% greater reduction than placebo
(pless than or equal to0.05) in subjects who had a moderate level of symptoms at baseline.
The treatment was safe and well tolerated in all groups.

About Circassia’s allergy T-cell vaccines

Circassia is developing a range of allergy treatments based on its proprietary
ToleroMune(R) technology, which utilises small sections of allergens (epitopes) to
generate regulatory T cells that suppress allergic immune responses, and thereby
desensitise patients. The company has successfully completed a number of phase II studies
with its cat, house dust mite, ragweed and grass allergy therapies. Clinical results show
that short treatment regimes with Circassia’s T-cell vaccines can greatly reduce patients’
allergic responses, without the need for adjuvants or other immune stimulators, while
proving extremely well tolerated. As a result, the treatments offer major potential
clinical benefits compared with existing therapies, and have significant market
opportunities. More than 150 million people suffer from allergic rhinitis in the US and
Europe, and over 25% of the population of the United States and a growing number of
Europeans are sensitive to ragweed pollen. As a result, the current allergy treatment
market is valued at approximately $12 billion per year.

About Circassia

Circassia was founded in 2006 by a team of highly experienced biotechnology scientists
and entrepreneurs, and is chaired by the former Chairman of GlaxoSmithKline, Sir Richard
Sykes. The company is based in the UK on the Oxford Science Park, and in Hamilton, Canada,
where its joint venture Adiga Life Sciences is located. Its ToleroMune technology was
developed originally by scientists at Imperial College, London. Having successfully
completed four fundraising rounds, Circassia has raised approximately GBP93 million ($159
million) and is backed by a syndicate of world-class institutional investors, including
Imperial Innovations and Invesco Perpetual.

* Hafner R et al. Validation of peptide immunotherapy as a new approach in the
treatment of allergic rhinoconjunctivitis: The clinical benefits of treatment with Amb a 1
derived T cell epitopes.


        Steve Harris
        Tel: +44(0)1865-784574


        Rob Budge
        RJB Communications
        Tel: +44(0)1865-760969
        Mobile: +44(0)7710-741241

SOURCE Circassia Ltd

Source: PR Newswire