Comparative evaluation of aqueous solution and oil emulsion formulations of 0.05% cyclosporine eye drops in dry eye disease - A randomized clinical trial

Purpose:To compare the clinical response of patients with moderate-to-severe dry eye disease to treatment with 0.05% cyclosporine eye drops as an aqueous solution or oil emulsion. Study Design:Prospective randomized clinical trial. Methods:An institutional study where 88 patients with moderate-to-severe dry eye was enrolled after written informed consent and randomized to receive either aqueous solution (Group 1) or oil emulsion (Group 2) 0.05% cyclosporine eye drops in twice daily dosing in addition to lubricant eyedrop 0.5% carboxymethylcellulose six times/day in both eyes. Comprehensive eye examination and baseline parameters were recorded, and clinical assessment was repeated at 4, 8, and 12 weeks. Parameters evaluated included ocular surface disease index score (OSDI), Schirmer test, tear break-up time (TBUT), corneal fluorescein staining - National Eye Institute (NEI) scoring, lipid layer thickness (LLT), tear meniscus height (TMH), non-invasive tear break-up time (NIBUT), percentage loss of meibomian glands, and impression cytology (number of goblet cells/hpf). Results:The mean age was 39 +/- 15.6 years and 42 +/- 17.7 years, and the M:F ratio was 26:19 and 20:24 in Groups 1 and 2, respectively. Both the groups showed comparable values at baseline. After treatment, there was statistically significant improvement over baseline values in both groups at 4, 8, and 12 weeks. At 12 weeks for the following parameters, there was no significant difference between the groups, though there was an improvement over baseline in Groups 1 and 2, respectively, as follows: OSDI score - 30.89, 33.28 (P < 0.001), Schirmer test - 5 mm, 4 mm (P < 0.001), TBUT - 2.65 sec, 3.07 sec (P < 0.001), NEI score - 2, 2 (P < 0.001) and the number of goblet cells/hpf - 1.5,9 (P = 0016, P = 0.001). A higher number of patients, by a value of 9, in Group 2 showed an increase in the number of goblet cells/hpf. The NIBUT value showed statistically significant improvement in Group 2 compared to Group 1 (P = 0.011). Group 2 also showed statistically significant improvement in TMH by the 8th week (P = 0.015) and in LLT by the 12th week (P < 0.001). Group 1 comparatively showed earlier improvement in LLT by the 4th week (P = 0.027). Conclusion:Both aqueous solution and oil emulsion 0.05% cyclosporine formulations appear to be equally effective in the management of dry eye disease with a comparatively better response with oil emulsion formulations.