An Open Label Prospective Randomized Trial to Compare The Efficacy Tolerability and Cost Effectiveness of Brand Name Versus Two Different Generic Drug of Fixed Combination Dorzolamide 2% and Timolol 0.5% in The Treatment of Primary Open Angle Glaucoma

Yıl 2018, Cilt: 1 Sayı: 3, 55 - 60, 31.12.2018

Mustafa Eliaçık

Öz

Purpose: To compare the efficacy tolerability and cost
effectiveness of brand name versus two different generic drug of fixed
combination dorzolamide 2% and timolol 0.5% in the treatment of primary open
angle glaucoma.

Methods: Sixty-six eyes of 66 patients with newly diagnosed,
open-angle glaucoma were included in this prospective, examiner masked,
randomized study. All patients underwent routine ophthalmic
examinations at baseline and 6 months of treatment. After initial examination, patients were randomly divided into three groups and
prescribed to use fixed combination treatment of dorzolamide/timolol
(D/T) brand name and two different generic name drops. Retrobulbar blood
flow was assessed with color Doppler imaging (CDI). At
end-of-treatment assessments, patients were requested to fill in a
questionnaire based on "the Comparison of Ophthalmic Medications for
Tolerability".

Results: Intraocular pressure (IOP) and CDI measurements were
similar at baseline. Compared to baseline, the brand name drop had a better resistive
index lowering effect than two other generic drugs, however the
difference was not statistically significant (p=0.056). Brand name D/T fixed
combination provided greater significant mean IOP reductions from baseline than
two other generic name drops (p=0.001). There were no statistically significant
differences in the IOP lowering effect between generic drops
(p=0.562). Tolerability was similar between groups. Generic
bottles failed to last a month for 80% patients.

Conclusions: Brand name product of D/T fixed combination is exactly more
effective in IOP reduction and seems to be having a better lowering effect on
resistive index, even a statistically significant result was not found.

Anahtar Kelimeler

generic drug, cost effectiveness, retrobulbar bloodflow, color doppler imaging

Kaynakça

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