Alcon Laboratories announced Sept. 21 that the FDA approved travoprost ophthalmic solution 0.004% formulated with a proprietary ionic-buffered preservative system for first-line treatment to reduce elevated IOP in patients with ocular hypertension or open-angle glaucoma.
Fort Worth, TX-Alcon Laboratories announced Sept. 21 that the FDA approved travoprost ophthalmic solution 0.004% (Travatan Z, Alcon Laboratories) formulated with a proprietary ionic-buffered preservative system (sofZia) for first-line treatment to reduce elevated IOP in patients with ocular hypertension or open-angle glaucoma.
"Available clinical trial data demonstrate the ocular hypotensive activity of travoprost preserved with [a proprietary ionic-buffered preservative system], and as an option that eliminates exposure to benzalkonium chloride [BAK], this PGA formulation is a particularly good choice for patients with existing ocular surface disease as well as for those at high risk for developing such problems," he added.
Investigators in the Travoprost Benzalkonium Chloride-Free Study Group compared the efficacy and safety of once-daily treatment with travoprost 0.004% with BAK with that of the formulation with the ionic-buffered preservative system in a multicenter, double-masked, randomized study enrolling almost 700 adults with open-angle glaucoma or ocular hypertension [J Glaucoma. 2007;16:98-103]. Patients were followed for a period of 3 months and returned for measurement of IOP at 8 a.m., 10 a.m., and 4 p.m. after 2, 6, and 12 weeks of therapy.
The study had a non-inferiority design, and across all three measurement times at all three visits, mean IOP reductions were similar in the two travoprost groups. Rates of hyperemia were 6.4% among patients treated with travoprost with the novel preservative system and 9% among those receiving the original BAK-containing formulation.
Another study was designed to compare the duration of IOP reduction with the BAK-free formulation of travoprost and the original preparation [J Glaucoma. 2008;17:217-222]. In this clinical trial, 109 patients were randomly assigned to once-daily treatment for 13 days with one of the two travoprost formulations. After the last dose, IOP measurements were taken every 12 hours for a total of 60 hours.
Analyses of mean IOP values showed no statistically significant difference between treatment groups in the 8 a.m. baseline measurement. For all assessments after the last dose, both treatment groups maintained an IOP reduction of at least 6 mm Hg compared with their 8 a.m. baseline, and there were no statistically significant differences between the two groups in mean IOP values at any of the assessment points following the last dose.
"Breakdown in the integrity of the ocular surface with the use of a topical medication containing BAK might be expected to allow increased intraocular penetration of the active agent with the potential for increased IOP-lowering activity," Dr. Gross said. "However, IOP measurements obtained in these clinical studies demonstrate there is no loss of efficacy when the preservative for travoprost is changed from BAK to [the novel preservative system] whether patients are followed for 24 hours postdosing or for up to 60 hours.
"The safety data in these studies also support a benefit for eliminating BAK," he concluded. "Although there was no statistically significant difference in the incidence of hyperemia between groups of patients using travoprost with [the novel preservative system] versus with BAK, removal or avoidance of BAK was associated with a substantial reduction in hyperemia."
Ronald L. Gross, MDE-mail: firstname.lastname@example.org
Dr. Gross is a consultant to Alcon Laboratories and Allergan.