Emulsion-based drops yield similar benefits for dry eye

May 15, 2005

Fort Lauderdale, FL—Results of a randomized, investigator-masked clinical study reinforce the usefulness of an existing unit-dose, emulsion-based artificial tear formula (Refresh Endura, Allergan) for improving the signs and symptoms of dry eye. In addition, outcomes show that an investigational multi-dose version formulated with a "vanishing" oxidative preservative (Purite) offers equally favorable efficacy, safety, and patient acceptability.

Fort Lauderdale, FL-Results of a randomized, investigator-masked clinical study reinforce the usefulness of an existing unit-dose, emulsion-based artificial tear formula (Refresh Endura, Allergan) for improving the signs and symptoms of dry eye. In addition, outcomes show that an investigational multi-dose version formulated with a "vanishing" oxidative preservative (Purite) offers equally favorable efficacy, safety, and patient acceptability.

Presented at the annual meeting of the Association for Research in Vision and Ophthalmology, the manufacturer-sponsored study randomized 158 subjects at 10 investigational centers to use of the commercially available unit-dose product or the multi-dose preparation. Eligible patients could have mild-to-severe dry eye symptoms, had to report a current need for artificial tears, and needed to demonstrate reduced scores at screening in Schirmer or Tear Break-up Time (TBUT) testing.

Participants were instructed to use their assigned artificial tear as needed, but at least 2 times a day, and returned for evaluation after 7, 30, 60, and 90 days. Of the patients enrolled, 132 (83.5%) completed the entire study.

Patient acceptability ratings were favorable for both formulations and rates of adverse events were low and not significantly different between treatments.

"By delivering oil, these emulsion-based formulas stabilize the tear film and reduce its evaporation. The expected clinical benefits of those effects are an improvement in tear break-up time, reduction in symptoms, and even improvement in staining, and those are exactly what were seen in this study," said Joseph G. Vehige, OD, senior director, clinical research and development, Consumer Eye Care R&D, Allergan, Irvine, CA.

"This investigation is also notable because it is one of the few trials that we are aware of that have compared a multi-dose and a unit-dose product head-to-head in an adequately sized patient population and using investigator-masked assessments," Dr. Vehige said. "The fact that outcomes with the two formulations were so similar supports the conclusion that with use of Purite, a preservative-containing ophthalmic product performs as close as one can get to a preservative-free preparation."

The patients enrolled in the study had a mean age of 51.5 years and were predominantly female (78%) and Caucasian (69%). They represented a spectrum of dry eye severity, although the majority (88%) had mild or moderate symptoms based on self-reports of dryness. There was significant correlation between patient reports of dryness severity and disease severity based on the OSDI scores. Mean conjunctival staining and mean corneal staining scores were relatively low.

"These data are consistent with the clinical observation that a large segment of dry eye patients primarily have a symptomatic condition accompanied by relatively minor pathological changes involving the ocular surface," said Peter A. Simmons, PhD, principal clinical research scientist, Consumer Eye Care R&D, Allergan, Irvine, CA. "The results of this study showed that in a typical dry eye patient population, these emulsion-based artificial tears were able to provide a good response with respect to ocular surface disease signs but importantly provide significant relief from bothersome symptoms that have motivated these individuals to seek treatment."

Product acceptability Product acceptability was evaluated in this study with a series of questions. The responses showed patients had positive impressions of both products. Notably, about 80% of patients in each study group "agreed" or "strongly agreed" that they liked using their assigned product; felt it made their eyes feel comfortable; was soothing; provided a cushion of moisture; and relieved dryness. However, for most of those questions as well as for several others, there was a slight edge favoring acceptability of the multi-dose preparation.