OCT 25, 2010
Although several basic and clinical studies have demonstrated the efficacy and safety of cyclosporine A (CsA ) in oleic emulsion for the treatment of dry eye, systems using oils to deliver treatment are poorly tolerated and provide a low bioavailability.
To address this issue, researchers evaluated the safety and efficacy of CsA in aqueous solution with Sophisen, a patented drug carrier, in a randomized, double-masked study of 183 patients with moderate to severe dry eye syndrome. This is a good article that demonstrates not only the effectiveness of cyclosporine but that a 0.1% dose may be more effective than 0.05%. Patients were randomly assigned to one of three treatment groups: twice daily cyclosporine A 0.1% aqueous solution, cyclosporine A 0.05% aqueous solution or aqueous vehicle. All patients were also instructed to use the lubricant, benzalkonium chloride preserved methylcellulose 0.5%, at least eight times a day.
At day 21, the 0.1% group experienced statistically significant improvement in four symptoms and three ocular signs of dry eye, while the 0.05% group improved in three symptoms and three ocular signs and the vehicle group improved in two ocular signs and two symptoms. At day 42, the 0.1% group showed improvement in four symptoms, while the 0.05% group showed improvement in one symptom and one ocular sign.
Comparing the three groups together, the 0.1% group performed better in four symptoms and the 0.05% group in one symptom, while the vehicle group showed no significant improvement.
The authors say the results suggest that an aqueous solution of cyclosporine A has a therapeutic effect on the symptoms and signs of dry eye that is independent of the vehicle and the coadjuvant lubricant treatment. They say further comparative studies are warranted to determine whether the aqueous solution used in this study is equivalent to the commercially available oil-based formulation.