AIM: To compare the monotheraphy efficacy of the brand latanoprost Xalatan and a similar latanoprost(Drenatan)regarding intraocular pressure(IOP)reduction in patients with primary open angle glaucoma(POAG).

METHODS: Sixty two patients(119 eyes)were enrolled in this observational, retrospective study. In the first visit, the patient came in using the brand latanoprost(Xalatan)and it was changed to the similar latanoprost(Drenatan). In the second visit, 12wk later, a complete ophtalmologic exam including slit lamp examination, Goldmann applanation tonometry, stereoscopic fundus examination, gonioscopy, ultrasound pachymetry, automated visual field testing was performed.

RESULTS:The mean IOP was 12.30±2.02mmHg and 12.38±2.05mmHg with using Xalatan and Drenatan, respectively. The P=0.559 demonstrates this relation. In fact, a correlation between the groups of R=0.987 points out the remarkable resemblance of both groups.

CONCLUSION: Both Drenatan and Xalatan have similar efficacy in reducing IOP. Such finding is pivotal to public health to reduce cost and maintain its policies concerning drug efficacy and safety, this is especially significant in countries in which treatment cost is a barrier for patient adhesion to treatment.