discovering dry eye
Positive Trial Results Leave Dry Eye Patients Hopeful
BY KELLY K. NICHOLS, OD, MPH, PHD

In mid-June, Inspire Pharmaceuticals announced positive results from their Phase III FDA trial of INS365 Ophthalmic drop for the treatment of dry eye disease, once again inspiring hope for symptomatic dry eye patients everywhere (no pun intended).  These results represent a positive step forward toward a marketable dry eye prescription medication.

Study Design

This six-month study was a double-masked comparison of the safety and efficacy of INS365 Ophthalmic 1.0% and 2.0% eye drops to placebo. Over 500 dry eye patients at 34 sites across the United States were enrolled. In this trial, INS365 Ophthalmic 2.0% eye drops demonstrated a highly statistically significant improvement (p-value < 0.001) over placebo for the primary objective endpoint, corneal staining. As well as achieving statistically significant results at the primary six-week endpoint, statistical signifi cance was achieved as early as two weeks and consistently observed throughout the 24-week study.

The primary subjective endpoint of the study, clearing the ocular symptom of foreign body sensation at six weeks, did not meet but approached statistical significance. The number of patients who cleared foreign body sensation was consistently higher on treatment compared to placebo throughout the study period. Moreover, there was a statistically significant improvement on this endpoint in favor of INS365 Ophthalmic at other time points for the greater than 80 percent of patients who complied with the protocol. In addition, INS365 Ophthalmic showed statistically significant improvements compared to placebo on various other ocular symptoms at multiple time points.

Summer in the South

Does humidity in the summer help patients with dry eye disease? I have always thought that dry eye in Denver during the summer, where the heat is very dry, is very different from dry eye in more humid locations. To avoid these types of environmental differences in testing INS365 ophthalmic, Inspire is sponsoring a study where patients are exposed to a controlled adverse environment (CAE) in which tem perature and humidity is strictly controlled. Further, to ensure there are no confounding effects of summer temperature and humidity, enrollment was halted for the summer months and will resume this fall. Following completion of this study, results will be submitted to the FDA for consideration. "If the ongoing trial succeeds and the FDA review process goes smoothly, the product could be approved and available sometime in 2004," says Don Kellerman, PhD, Senior Vice President of Development, Inspire Pharmaceuticals.

Let's All Hold Hands

Inspire Pharmaceuticals, Inc. is a relatively new pharmaceutical company that focuses its research primarily on the discovery and development of new drugs to treat diseases characterized by deficiencies in the body's innate defense mechanisms of mucosal hydration and mucociliary clearance. Inspire has formed development and commercialization alliances with Allergan, Inc., Kissei Pharmaceutical Co., Ltd., Santen Pharmaceutical Co., Ltd. and Kirin Brewery Co., Ltd. In June 2001, Inspire entered into a development and commercialization agreement with Allergan, Inc. for INS365 Ophthalmic and Allergan's Restasis, both for the treatment of dry eye. INS365 Ophthalmic and Restasis are complementary products targeted to different patient needs. Within the next two years one, or both, of these medications may reach the market, benefiting dry eye patients everywhere.

Dr. Nichols is assistant professor of clinical optometry at The Ohio State University College of Optometry in the area of dry eye research.