ISTA Pharmaceuticals has started a randomised, placebo-controlled, parallel-group environmental Phase 2 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 study will investigate 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 Pharma expects to recruit approximately 600 patients in Texas who will be treated with either Bepotastine besilate nasal spray or placebo for two weeks.

ISTA Pharma president and CEO Vicente Anido said that this nasal spray drug candidate represents an expansion of their 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.

"The results from our Phase 1/2 clinical study of Bepotastine besilate nasal spray, announced in October 2010, showed a patient response to the nasal spray without serious side effects," Anido said.

"We expect to have preliminary data from this Phase 2 Mountain Cedar pollen study during the first half of 2011."