Fixed combination of travoprost and timolol maleate reduces intraocular pressure in Japanese patients with primary open-angle glaucoma or ocular hypertension: analysis by prostaglandin analogue

Tadashi Nakano,1 Shiro Mizoue,2 Nobuo Fuse,3 Aiko Iwase,4 Shun Matsumoto,5 Keiji Yoshikawa6 On behalf of the I.CHANGE2 study group 1Department of Ophthalmology, The Jikei University School of Medicine, Nishi-Shimbashi, Minato-ku, Tokyo, 2Department of Ophthalmology, Ehime University Graduate School of Medicine, Shitsukawa, Toon-city, Ehime, 3Department of Integrative Genomics, Tohoku Medical Megabank Organization, Seiryo-machi, Sendai, Miyagi, 4Tajimi Iwase Eye Clinic, Hon-machi, Tajimi, Gifu, 5Department of Ophthalmology, Tokyo Teishin Hospital, Fujimi, Chiyoda-ku, 6Yoshikawa Eye Clinic, Naka-machi, Machida, Tokyo, Japan Background: We have shown a decrease in mean intraocular pressure (IOP) by switching to travoprost/timolol fixed combination (TTFC) in subjects receiving prostaglandin analogue (PGA) monotherapy and requiring additional medication in a previous report. For analyzing factors affecting IOP reduction, baseline IOP and preceding PGA were selected as statistically and clinically significant factors. In this report, we examine IOP-lowering effect and adverse drug reactions by preceding PGA.Methods: Patients with primary open angle glaucoma or ocular hypertension who received monotherapy with one of four PGAs (travoprost, latanoprost, tafluprost, or bimatoprost) for at least 3 months at 26 institutions and were determined to require additional medication by their primary physician were included. IOP reduction and adverse events were examined at 4, 8, and 12 weeks for each of four PGAs after switching to TTFC.Results: In total, 157 patients who could be followed up for at least 4 weeks after switching to TTFC were included in the efficacy analysis. Multiple regression analysis was performed, and baseline IOP and PGA were found to be significant factors to IOP reduction. IOP reduction at week 12, adjusted with the regression model, was -3.5, -1.8, and -1.4 mmHg in the tafluprost, latanoprost, and travoprost groups, whereas it was -0.5 mmHg in the bimatoprost group. Along with differences in baseline IOP between groups, an IOP-lowering effect of >1 mmHg was noted in the tafluprost, latanoprost, and travoprost groups after the switch. IOP was maintained at 13.8–14.8 mmHg throughout the follow-up period. No serious adverse events or noteworthy issues were observed in any group after the switch.Conclusion: Clinically significant IOP-reducing effects of TTFC were observed in the latanoprost, travoprost, and tafluprost groups when switching from each PGA monotherapy, while there were some differences in effects between groups, with minimal safety concerns. Keywords: adverse event intraocular pressure, prostaglandin analogue, switching therapy, travoprost/timolol fixed combination