Inspire Pharmaceuticals Inc announced encouraging and supportive results from study 03-108, a Phase IIIb study of diquafosol for the treatment of dry eye. This exploratory study included assessments from both a conventional environmental component and an experimental Controlled Adverse Environment (CAE) chamber designed to exacerbate dry eye.

The study was a four-week, placebo-controlled, double-masked comparison of the safety and efficacy of 2% diquafosol tetrasodium ophthalmic eye drops to placebo, administered four times daily in 222 dry eye patients. Endpoints included ocular staining (a key objective measure of corneal and conjunctival surface health) and ocular discomfort (a measure of patient-reported symptoms) measured in both the environmental and the CAE chamber portions of the study.

In this study, as in previous studies, diquafosol was well tolerated, with the incidence of adverse events similar to placebo. There were no treatment-related serious adverse events reported. As stated previously, data from the study will be submitted to the Food and Drug Administration as part of the 120-day safety update.

In the environmental portion of the study, treatment with diquafosol resulted in statistically significant improvements in ocular staining compared to placebo. These findings are consistent with those demonstrated in the Phase II and III studies submitted in Inspire's New Drug Application for diquafosol.

In the experimental CAE chamber portion of the study, statistical significance was not achieved with respect to the primary endpoints of ocular staining and discomfort after exposure in the CAE chamber. Patients treated with diquafosol showed an improvement in ocular staining to a greater extent than patients receiving placebo, although not significantly so.

Dry eye is a painful, burning and irritating condition involving abnormalities and deficiencies in the tear film due to a variety of causes. It affects approximately 10 million North Americans and is one of the most frequent patient complaints reported to ophthalmologists and optometrists. The majority of dry eye patients rely on artificial tears to relieve symptoms.