Dry eye syndrome has been estimated to affect more than 5 million Americans, yet there is only one FDA-approved eye drop, cyclosporine ophthalmic emulsion 0.05%, for its treatment.
Dry eye syndrome has been estimated to affect more than 5 million Americans,1 yet there is only one FDA-approved eye drop, cyclosporine ophthalmic emulsion 0.05% (Restasis, Allergan), for its treatment. A recent survey found that about 94% of eye-care practitioners have expressed dissatisfaction with existing treatments for dry eye and want more treatment options.2
An array of therapeutic approaches to treating dry eye are currently under investigation and show potential. One of the most commonly studied topics is anti-inflammatories, many of which are based on existing systemic medications that have been reformulated for topical delivery to the eye.
Another anti-inflammatory in the pipeline is an LFA-1 antagonist (SAR 1118, SARcode) that targets a broad range of ocular inflammatory conditions, and has demonstrated significant potency in preventing cell adhesion and cytokine production, which can be associated with ocular surface inflammation. In a phase II, randomized, multicenter, double-masked study comparing SAR 1118 (0.1%, 1%, 5%) with placebo, a total of 230 subjects received drops twice daily for 12 weeks.6 Results from the phase II study were reported in May 2010 and showed improvement for signs and symptoms of dry eye in only 12 weeks, which suggests a more rapid method of improvement.7
Resolvins, naturally occurring lipid mediators that inhibit the production and transportation of inflammatory cells, also are being investigated heavily for the treatment of dry eye. Resolvins have been used preclinically for the treatment of a variety of diseases including rheumatoid arthritis and retinal disease.
One such resolvin (RX-10045, Resolvyx) is scheduled to enter a phase III randomized, placebo-controlled, multicenter study this year. Phase II trials for the resolvin were conducted with a 28-day, randomized, multicenter, placebo-controlled study in 232 patients with moderate dry eye, in which the drug was administered twice daily. The results from the trial showed significant dose-dependent improvement from baseline in symptoms, with improvement observed across all symptoms evaluated in the study, including dryness, ocular discomfort, and effect of corneal staining in the CAE model.8