A phase II randomized trial to evaluate the long-term (12-week) efficacy and safety of OC-01 (varenicline solution) nasal spray for dry eye disease: The MYSTIC study

Purpose: Dry eye disease is characterized by loss of tear film stability. OC-01 (varenicline solution) is a small-molecule nicotinic acetylcholine receptor agonist administered as a nasal spray that stimulates tear production. Methods: In MYSTIC (NCT03873246) patients aged ≥22 years with dry eye disease were randomized 1:1:1 to OC-01 0.03 mg, OC-01 0.06 mg, or vehicle (n = 41 per group), administered twice daily via intranasal spray, for 12 weeks (84 days). Primary efficacy endpoint was mean change from baseline in anesthetized Schirmer's test score (STS) in study eye at day (D) 84. Results: Patients receiving OC-01 0.03 and 0.06 mg had statistically significantly increased tear production at D84 versus vehicle; least squares mean changes from baseline in STS were 10.8 mm and 11.0 mm for OC-01 0.03 and 0.06 mg, respectively. A trend toward a higher proportion of patients experiencing ≥10-mm improvement in STS from baseline was observed with OC-01 0.03 mg (36.6%; p > 0.05), and was significant for OC-01 0.06 mg (48.8%; p = 0.024), versus vehicle (24.4%). Non-ocular treatment-emergent adverse events (TEAEs) were reported by 21 patients; the most common was sneezing (OC-01 0.03 mg, 2 [4.9%]; OC-01 0.06 mg, 3 [7.3%]), with similar frequencies between treatment groups. No severe or serious TEAEs were reported. Conclusions: OC-01 (varenicline solution) nasal spray improved tear production in patients with dry eye disease over a long-term (12-week) period, and represents a receptor neuro-activator with a nasal route of administration that spares the ocular surface to stimulate tear production.