ISTA Pharmaceuticals, Inc. announced it has initiated a phase II clinical study of bepotastine besilate nasal spray for the treatment of symptoms associated with seasonal allergic rhinitis, the inflammation of the nasal passages caused by allergies. The randomized, placebo-controlled, parallel-group environmental study will evaluate the safety and efficacy of bepotastine besilate, dosed twice daily, in patients presenting with allergic rhinitis caused by one of the most potent seasonal allergy triggers, Mountain Cedar pollen.

ISTA expects to enroll approximately 600 patients in Texas who will be treated with either bepotastine besilate nasal spray or placebo for two weeks. Patients will grade both individual nasal and ocular symptoms on a daily basis.

“This nasal spray drug candidate represents an expansion of our focus in prescription allergy treatments, which currently includes Bepreve (bepotastine besilate ophthalmic solution) 1.5% for the treatment of ocular itching associated with allergic conjunctivitis,” commented Vicente Anido, Jr., PhD, president and chief executive officer of ISTA. “The results from our phase I/II clinical study of bepotastine besilate nasal spray, announced in October 2010, showed a robust patient response to the nasal spray without serious side effects. We expect to have preliminary data from this phase 2 Mountain Cedar pollen study during the first half of 2011.”

ISTA submitted the Investigational New Drug (IND) application to the US Food and Drug Administration (FDA) for bepotastine besilate nasal spray in November 2010.

According to the American Academy of Allergy Asthma & Immunology (AAAAI), approximately 60 million Americans are affected by allergic rhinitis, an inflammation of the nasal passages caused by exposure to certain allergens, such as pollen from trees, grass and plants, animal dander, feathers, dust mites and moulds. Allergic rhinitis is characterized by a number of symptoms, including sneezing, nasal congestion, nasal itching and runny nose. The eyes, ears, sinuses and throat also can be affected. Current treatments for allergic rhinitis include antihistamines, mast cell stabilizers, anti-inflammatories, and steroids. Based on data from IMS Health in the US, approximately 43.3 million prescriptions were filled for nasal allergy treatments in 2009, resulting in sales of approximately $2.2 billion.

Bepotastine besilate is a non-sedating, highly selective antagonist of the histamine H1 receptor. It has a stabilizing effect on mast cells, and it suppresses the migration of eosinophils into inflamed tissues. The compound's primary mechanisms of action suggest that it is a potentially effective treatment for nasal symptoms associated with seasonal allergic rhinitis.

Bepotastine besilate has been approved in Japan for systemic use in the treatment of allergic rhinitis since 2000 and for urticaria/pruritus since 2002. It is marketed in Japan by Mitsubishi Tanabe Pharma Corporation (formerly Tanabe Seiyaku Co., Ltd.) under the brand name Talion. Talion was co-developed by Tanabe Seiyaku and Ube Industries, Ltd., who discovered bepotastine besilate. In 2001, Tanabe Seiyaku granted Senju Pharmaceutical Co., Ltd., exclusive worldwide rights, with the exception of certain Asian countries, to develop, manufacture and market bepotastine besilate for ophthalmic use. In 2006, ISTA licensed the exclusive North American ophthalmic rights to bepotastine besilate from Senju. In 2007, ISTA licensed exclusive North American rights to nasal dosage forms of bepotastine besilate from Tanabe Seiyaku and obtained a future right to negotiate for a North American license to oral dosage forms of bepotastine besilate for allergy treatment.

ISTA's eye drop formulation of bepotastine besilate, Bepreve (bepotastine besilate ophthalmic solution) 1.5%, was approved by the US Food and Drug Administration (FDA) in September 2009 for the treatment of ocular itching associated with allergic conjunctivitis. ISTA's nasal spray formulation for seasonal allergic rhinitis currently is an investigational drug in clinical studies and has not yet been approved by the FDA.

ISTA Pharmaceuticals, Inc., is the fourth largest and fastest growing branded prescription eye care business in the United States, with an expanding focus on allergy therapeutics. ISTA currently markets five products, including treatments for ocular inflammation and pain post-cataract surgery, glaucoma and ocular itching associated with allergic conjunctivitis.