Efficacy and safety of varenicline nasal spray in dry eye disease: a systematic review and meta-analysis of randomized controlled trials

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• Picked for Ophthalmology (top studies of the week, 26 July 2026).

Abstract

BACKGROUND: Dry eye disease is a multifactorial ocular surface disorder characterized by tear film instability and inflammation, leading to impaired visual function and reduced quality of life. Varenicline solution nasal spray is a nicotinic acetylcholine receptor agonist stimulates the trigeminal pathway to enhance basal tear production. METHODS: We searched electronic databases (PubMed, Scopus, and Web of Science) from inception to February 2026 to identify randomized controlled trials (RCTs) assessing varenicline nasal spray (0.03 mg or 0.06 mg twice daily) in adults with dry eye symptoms. Primary outcomes included the proportion of patients achieving ≥ 10-mm improvement in Schirmer test score (STS) and mean change in STS. Secondary outcomes included Eye Dryness Score (EDS), corneal fluorescein staining and treatment-emergent adverse events (TEAEs). Meta-analyses were conducted using random-effects models. The primary analysis focused on the approved 0.06 mg dose, with dose-based subgroup analyses comparing 0.03 mg and 0.06 mg doses where data were available. RESULTS: Seven randomized controlled trials were included. In the primary 0.06 mg analysis, varenicline nasal spray significantly improved mean Schirmer test score change (MD = 5.52 mm; 95% CI: 4.08 to 6.97; p < 0.0001) and increased the proportion of patients achieving a ≥ 10-mm Schirmer test score improvement (RR = 1.86; 95% CI: 1.50 to 2.30; p < 0.0001). Eye Dryness Score showed a non-significant numerical improvement (MD =  - 4.38; 95% CI: - 12.02 to 3.25; p = 0.2601). Dose-based subgroup analyses showed consistent Schirmer test benefits for both 0.03 mg and 0.06 mg doses. Corneal fluorescein staining was not significantly improved. Ocular adverse events and reduced visual acuity were comparable between groups, while non-ocular adverse events, particularly sneezing, were more frequent with varenicline. CONCLUSIONS: Varenicline nasal spray improved tear production, with less consistent effects on symptoms and corneal staining. Ocular safety was comparable, but sneezing was more frequent.

Abstract as published, via PubMed.