Varenicline nasal spray may improve tear production in dry eye disease

A recent study evaluating the efficacy of varenicline nasal spray (VNS) versus vehicle/placebo for treating dry eye disease has concluded that VNS use improves Schirmer test scores over 28 days of treatment.

They noted more incidence of cough and throat irritation in the VNS group.

The lead researcher of this study, “The efficacy and safety of varenicline nasal spray for the management of dry eye signs: a systematic review and meta-analysis”, is Dr Bader Bashrahil and is published in BMC Ophthalmology.

It is already known that the leading cause of DED is persistently unstable tear film causing ocular discomfort. This eye condition is treated using tear supplementation. Emerging evidence supports the effectiveness of nicotinic acetylcholine receptor (nAChR) agonists (e.g., varenicline and simpinicline) nasal sprays for managing DED.

In the present study, the team assessed the efficacy and safety of varenicline nasal spray (VNS) for DED treatment using databases like CENTRAL, Medline, and Embase.

The mean change in the anaesthetized STS or Schirmer test score, a measure of basal tear production, from baseline was the efficacy endpoint and serious adverse events (SAEs) and adverse events (AEs) were the safety endpoints.

The main Results of the study could be summarised as follows:

• A total of 3 RCTs with 1063 participants met the eligibility criteria and had a low risk of bias.
• On day 28, there was an increase in the mean STS change from baseline.
• There was no significant difference between VNS and placebo in SAE and ocular AE frequency.
• They found VNS had a substantial effect on developing nasal cavity-related AEs.

They said that VNS improved efficacy endpoints and increased the frequency of nasal cavity-related AEs like cough and throat irritation.

They noted there were neither SAEs nor ocular AEs.

The study limitations include low numbers, inconsistent pooled results and high heterogeneity.

They mentioned that upcoming studies should focus on comparing its safety and efficacy against currently established management options.

Further reading:

Bashrahil, B., Taher, N., Alzahrani, Z. et al. The efficacy and safety of varenicline nasal spray for the management of dry eye signs: a systematic review and meta-analysis. BMC Ophthalmol 23, 319 (2023). https://doi.org/10.1186/s12886-023-03069-y