BAK does not increase efficacy of travoprost in lowering IOP

The presence of benzalkonium chloride (BAK) has no impact on the safety or efficacy of travoprost in lowering intraocular pressure (IOP), according to a study published in the April/May 2008 issue of the Journal of Glaucoma.

Ronald L. Gross, MD of the McPherson Retina Center, Houston, US and colleagues conducted a randomized, double-masked study to compare travoprost ophthalmic solution 0.004% (Travatan Z; Alcon) formulated without BAK to travoprost ophthalmic solution 0.004% formulated with BAK (Travatan; Alcon). Study subjects (n=109) were treated for two weeks, once daily either with travoprost or with travoprost plus BAK, after which IOP was measured every 12 hours for 60 hours.

Mean IOP at baseline was 26.9 mmHg for the BAK-free group and 27.1 mmHg for the travoprost plus BAK group. At 60 hours, mean IOP was 20.8 mmHg for both the BAK-free group and the travoprost plus BAK group. Although variations in IOP measurements were noted at the 12-hour monitoring stages, these were not statistically significant; intra-group variations were never more than ±0.6 mmHg.

The researchers concluded that travoprost has a similar efficacy and safety profile for the lowering of IOP regardless of the presence of BAK as a preservative.