Adjunctive glaucoma therapy use associated with travoprost, bimatoprost, and latanoprost

Purpose: This study contrasts the utilization of adjunctive medication associated with travoprost, bimatoprost, or latanoprost, as primary glaucoma therapies. Methods: Patients in the Medco Health database who initiated prostaglandin analog therapy on travoprost, bimatoprost or latanoprost between January 1, 2002 and July 31, 2002 were selected if they had no prostaglandin analog use in the prior 6 months. Patients were also required to have 12 months of prostaglandin therapy subsequent to the initial prescription. Data were available through July 31, 2003. The t-test and chi-square were used where appropriate to calculate p-values and assess significant differences. Results: A total of 13 171 benefit-eligible subjects were identified of which 8381 (64%), 2637 (20%), and 2153 (16%) patients were treated with latanoprost, bimatoprost, and travoprost, respectively. There were no significant differences in mean age or gender between the three study groups with the exception that latanoprost patients were statistically older than travoprost patients (69.0 vs. 68.0). This was not considered a clinically meaningful difference. Overall, patients using travoprost or bimatoprost had a significantly lower rate of adjunctive medication use compared to patients starting on latanoprast monotherapy (22.5%, 23.2%, and 30.2%, respectively). Therefore, for every 14 patients treated with latanoprost instead of travoprost or bimatoprost, one additional patient would be expected to need adjunctive therapy with another agent. The difference between travoprost and bimatoprost patients was not significant. Conclusions: The use of adjunctive medications to control intraocular pressure was significantly higher for latanoprost patients compared to travoprost and bimatoprost patients. This finding should be interpreted in the context that this study was based only on prescription claims data. It is important to simplify ophthalmic medical regimen as it is more cost effective, better for the patient, and minimizes the washout effect from administering two eye medications within 5 min. Decreasing the complexity of the patients' drug regimen may lead to increased adherence to prescribed therapy and a decreased risk of the incidence of blindness.