The company has enrolled more than 600 patients in the randomized, placebo-controlled, parallel-group environmental study.
The double-masked study is evaluating the safety and efficacy of the combination nasal spray, dosed twice daily, in patients presenting with allergic rhinitis caused by Mountain Cedar pollen.
The patients will be treated with one of four formulations, bepotastine besilate-steroid combination nasal spray, a nasal spray containing only one of the two active agents, or placebo nasal spray.
ISTA clinical research and medical affairs vice president Timothy McNamara said the patient enrollment has been rapid and very successful in the Phase II trial.
"We expect to report results of the BEPOSONE Phase II trial in the first half of 2012," McNamara added.