Scottsdale, AZ—Systane (Alcon Laboratories) represents a compatible choice for artificial tear supplementation in dry eye patients being treated with topical cyclo-sporine ophthalmic emulsion 0.05% (Re-stasis, Allergan), according to clinicians who have used that combination in their practices and formally tested it.
Kenneth N. Sall, MD, and Stephen Cohen, OD, participated as investigators in a randomized, investigator-masked clinical trial comparing the adjunctive use of Systane and Refresh Tears in patients receiving cyclosporine for moderate-to-severe dry eye. The study results showed there was a lack of product-related adverse events in patients using Systane plus cyclosporine, indicating that Systane could be used safely together with cyclosporine. In addition, the findings also suggested that the dual regimen of Systane plus cyclosporine may offer clinical advantages compared with combination treatment using cyclosporine plus Refresh Tears.
"Onset of efficacy with topical cyclo-sporine treatment takes several weeks or longer, so patients are instructed to continue using artificial tears for symptomatic relief," said Dr. Cohen, an optometrist in private practice in Scottsdale, AZ. "Premarketing clinical trials with topical cyclosporine were conducted using Refresh Tears for supportive therapy, so it was important to determine if other artificial tears could be used in combination safely and without altering the efficacy of cyclo-sporine. Based on the results of a well-designed clinical trial, Systane appears to be an excellent choice for concomitant, supportive therapy with cyclosporine."
"Therefore, it is extremely important to use an artificial tear that complements cyclosporine, and this study shows cyclo-sporine with Systane was superior to cyclosporine with Refresh Tears for improving the signs and symptoms of dry eye disease," he said.
Compatible choice The compatibility trial randomized 61 patients to one of three treatment groups: cyclosporine plus Systane, cyclosporine plus Refresh Tears, or Systane alone. Eligible patients had to have corneal staining ≥3 based on the National Eye Institute grid, ≤7-mm wetting in Schirmer testing performed without anesthesia, and be using artificial tears "at least some of the time."
Topical cyclosporine was administered twice daily and Systane was administered four times daily when used as monotherapy. Patients assigned to one of the combination groups were instructed to instill the artificial tears at least once a day as supportive therapy, but not concurrently when instilling the cyclosporine.
The study had a 6-month duration, and at its conclusion there were statistically significant differences favoring the combination of cyclosporine + Systane versus cyclosporine + Refresh Tears in analyses of corneal staining. Also, there was a trend favoring cyclosporine + Systane for better improvement in tear film break up time.
"Although artificial tears are generally considered palliative therapy for dry eye, as a principal investigator in clinical trials evaluating Systane alone, I was not overly surprised to see that Systane may enhance the results with cyclosporine," Dr. Cohen said.
"Systane has been said to provide a 'power nap' for the eyes. It contains HP-Guar that binds preferentially to the hydrophobic sites of damaged surface epithelium and also crosslinks with borate ions in the Systane solution," he added. "The crosslinking occurs through a pH-induced polymerization reaction when the artificial tears come into contact with the tear film and the resultant polymer provides a long-lasting protective barrier for the corneal epithelium and conjunctiva that enables cellular regeneration. Consequent-ly, it is not surprising to see that use of Systane is associated with an improvement in the overall tear film and therefore in the tear film break-up time."