Ocular Surface Tolerability of Prostaglandin Analogs in Patients with Glaucoma or Ocular Hypertension

To compare the ocular surface tolerability of latanoprost 0.005% preserved with 0.02% benzalkonium chloride (BAK), bimatoprost 0.03% preserved with 0.005% BAK, and travoprost 0.004% preserved with the proprietary preservative system sofZia in patients previously treated with latanoprost. This randomized, multicenter, investigator-masked, parallel-group study enrolled patients with open-angle glaucoma or ocular hypertension who had been on latanoprost monotherapy for at least 4 weeks. At baseline, patients were randomized to receive once-daily bimatoprost (n=35), latanoprost (n=38), or travoprost (n=33) monotherapy for 3 months. Follow-up visits were at week 1, month 1, and month 3. The primary outcome measure was physician-graded conjunctival hyperemia at month 3. Secondary outcome measures included corneal staining with fluorescein and tear breakup time (TBUT). There were no significant differences among the treatment groups in conjunctival hyperemia scores, corneal staining, or TBUT at the latanoprost-treated baseline or at any follow-up visit. Baseline mean (standard error of the mean) values were as follows--conjunctival hyperemia: bimatoprost 0.74 (0.10), latanoprost 0.74 (0.11), travoprost 0.86 (0.12), P=0.692; corneal staining: bimatoprost 0.59 (0.12), latanoprost 0.70 (0.13), travoprost 0.48 (0.11), P=0.423; TBUT (in seconds): bimatoprost 9.1 (1.0), latanoprost 8.6 (0.8), travoprost 7.9 (0.8), P=0.578. Month 3 values were as follows--conjunctival hyperemia: bimatoprost 0.80 (0.12), latanoprost 0.74 (0.10), travoprost 0.98 (0.13), P=0.340; corneal staining: bimatoprost 0.71 (0.78), latanoprost 0.47 (0.64), travoprost 0.36 (0.62), P=0.110; TBUT (in seconds): bimatoprost 9.7 (5.3), latanoprost 9.2 (5.3), travoprost 9.7 (6.3), P=0.909. There were no significant differences among bimatoprost (preserved with 0.005% BAK), latanoprost (preserved with 0.02% BAK), and travoprost (preserved with sofZia) in objective clinical measures of ocular tolerability, including physician-graded hyperemia, corneal staining, and TBUT after 3 months of treatment. Longer-term studies are needed to further evaluate the ocular surface tolerability of these prostaglandin analogs.