The Effect of Decreasing the Dosage of Cyclosporine A 0.05% on Dry Eye Disease After 1 Year of Twice-Daily Therapy

Abstract

To evaluate the effect of decreasing topical cyclosporine 0.05% (tCSA) (Restasis; Allergan, Irvine, CA) from twice-daily dosing to once-daily dosing in patients who have already completed 12 months of twice-daily therapy for dry eye disease. Prospective, randomized, single-masked, parallel group comparison. One hundred patients who had already been treated with tCSA twice daily for more than 1 year were randomized either to continue tCSA twice daily (n = 50) or to decrease tCSA once daily (n = 50). Clinical measurement of dry eye variables was performed for all patients at baseline, 3 months, and 6 months. Mean data were used for within-group (longitudinal analysis) and between-group comparisons (once daily vs. twice daily). Fluorescein tear break-up time, corneal fluorescein staining score, lissamine green staining score, Schirmer tear test, and ocular surface disease index. At the end of the study, patients whose treatment dose was decreased to once daily demonstrated statistically significant improvement in tear break-up time [4.13 seconds (n = 37) vs. 3.11 seconds at baseline (n = 50); P = 0.0003] and lissamine green staining score [4.42 (n = 37) vs. 6.51 at baseline (n = 50); P = 0.024]; fluorescein staining score, Schirmer test results, and ocular surface disease index did not change significantly (P > 0.05). Furthermore, the once-daily group demonstrated significantly superior ocular surface disease index compared with the twice daily group [15.91 (n = 37) vs. 22.62 (n = 48); P = 0.0496]. The remaining outcome measures between once daily and twice daily were not significantly different (P > 0.05). Seven of 50 patients (14%) in the once-daily group (vs. 0% in the twice-daily group) ended the study early because of worsening dry eye symptoms (P < 0.05) and went back to twice-daily dosing. For patients with dry eye that has been controlled with tCSA twice daily for at least 1 year, decreasing to tCSA once daily may still allow suppression of the dry eye disease.