Comparative Efficacy and Safety of 0.05% Cyclosporine A and 3% Diquafosol Sodium in Dry Eye Disease: A Systematic Review and Meta-Analysis with Trial Sequential Analysis

Background: Dry Eye Disease (DED) is a multifactorial ocular surface disorder characterized by tear film instability and inflammation. Cyclosporine A, an immunomodulator, and Diquafosol sodium, a mucin secretagogue, represent two distinct therapeutic pathways. However, current evidence directly comparing their clinical efficacy is inconsistent. This meta-analysis aimed to compare treatment outcomes and efficacy between 0.05% Cyclosporine A and 3% Diquafosol sodium in patients with moderate-to-severe DED. Methods: In January 2026, we conducted a systematic search of PubMed, Scopus, Web of Science, and the Cochrane Library for randomized controlled trials directly comparing 0.05% Cyclosporine A to 3% Diquafosol sodium in adult patients with moderate-to-severe DED. For the meta-analysis, we used R 4.5.0 with R Studio 2024.12.1+563. Results: We included six RCTs with a total of 859 patients. No significant differences were found between Cyclosporine A and Diquafosol sodium in Tear Break-Up Time (TBUT) at 4, 8, or 12 weeks. Cyclosporine A showed a suggestive greater improvement in Schirmer test scores at 4 weeks (SMD = 0.35, 95% CI 0.07 to 0.63). A modest benefit in symptom scores favoring Diquafosol sodium was observed at 12 weeks (SMD = 0.23, 95% CI 0.06 to 0.41). Subgroup analysis suggested this symptomatic benefit may be more pronounced in patients with severe disease, although subgroup interaction tests were not statistically significant. There were no significant differences in corneal or conjunctival staining at any time point. The risk of adverse events did not differ significantly between treatments. Conclusions: Early improvement in tear production showed a potential benefit for Cyclosporine A, while longer-term symptomatic relief showed a potential benefit for Diquafosol sodium, with suggestive evidence in severe disease. However, these findings should be interpreted cautiously, given the methodological limitations and inconclusive TSA evidence for several outcomes. Future large-scale, standardized trials with extended follow-up are warranted to confirm these findings.