Journal of Medical Economics

Longitudinal glaucoma treatment patterns with brinzolamide versus dorzolamide

Michael T Halpern MD PhD1, Sonja Sorensen MPH1,
Dave Covert MBA2, John Hutton BSc Econ BPhil1

1MEDTAP International, Inc.
2Alcon Laboratories, Inc.

Key words: resource utilisation, glaucoma, carbonic anhydrase inhibitors, retrospective analysis, treatment failure

Summary
We analysed retrospective US medical claims data to evaluate longitudinal usage patterns (modification of treatment over time) for glaucoma patients receiving the ophthalmic carbonic anhydrase inhibitors (CAIs) brinzolamide or dorzolamide. Patients enrolled in a healthcare plan at least 2 months before and 6 months after their first CAI pharmacy claim were eligible. Treatment failures, patients who switched off CAI and/or added concomitant glaucoma medications, were calculated at 1, 2, and 6 months. Six hundred and twenty-six patients met the inclusion criteria, 220 for brinzolamide and 406 for dorzolamide. Overall 6 months treatment failure rates were 49.1% and 53.2% for brinzolamide and dorzolamide, respectively. Six month failure rate due to discontinuing CAI only were 20.9% for brinzolamide and 24.6% for dorzolamide, while median days to treatment failure were 160 and 106, respectively (p=0.027). Evaluation of differences in longitudinal usage patterns for CAIs may be helpful in determining appropriate treatments for glaucoma patients.