COMfort Eye Trial (COMET) results - a non-inferiority, randomized, investigator-masked, two-parallel group, phase III clinical trial, to evaluate the efficacy and safety of a preservative free formulation of latanoprost versus a reference drug (Xalatan®) in patients with primary open-angle glaucoma (POAG) or ocular hypertension (OHT).

Aim: To prove non-inferiority of preservative-free (PF) latanoprost versus benzalkonium chloride (BAK) containing latanoprost in lowering intraocular pressure (IOP) in primary open-angle glaucoma (POAG) or ocular hypertension (OHT) patients.
Design and Methods: This phase III, randomized, investigator-masked trial primarily aimed to demonstrate non-inferiority of YSLT PF latanoprost 50 μg/ml (Yonsung GmbH) to latanoprost (Xalatan®) 50 μg/ml (Pfizer) in reducing IOP from Baseline to Week 12. Secondary aims included conjunctival hyperemia evaluation and difference in ocular comfort levels. Total 130 patients with POAG or OHT were enrolled and randomized (1:1 ratio) to receive YSLT or latanoprost, instilling eye drops daily for 12 weeks.
Results: At Week 12, mean diurnal IOP reduction was -7.67 ± 2.104 mmHg for YSLT PF latanoprost and -7.77 ± 2.500 for latanoprost. The 97.5% confidence interval of between-treatment group difference in IOP reduction from Baseline to Week 12 was [-0.846, +∞), not crossing the non-inferiority margin of -1.5 mmHg. A low incidence of mild topical treatment emergent adverse events (TEAEs) was observed in both groups, while no serious TEAEs were reported.
Conclusions: YSLT eye drops demonstrated non-inferiority to latanoprost in reducing IOP. Both products were well tolerated without serious TEAEs reported.