The aim of the study was to compare the intraocular pressure (IOP) lowering efficacy and cost analysis of Brinzolamide 1%/Brimonidine 0.2% fixed combination (BBFC) therapy versus separate concomitant Brinzolamide 1% and Brimonidine 0.2% (Brinz + Brim) therapy. Methods: A prospective, randomized, comparative, cross over, 12-week study was conducted on forty patients of primary open angle glaucoma or ocular hypertension. Enrolled patients were randomized into two groups (Group A and B) of twenty patients each. For the first 6 weeks of the 12-week study period, Group A patients received Brinzolamide 1%/Brimonidine 0.2% fixed combination (BBFC) therapy and Group B patients received concomitant Brinzolamide 1% and brimonidine 0.2% (Brinz + Brim) therapy, each given twice daily. After the 6-week follow-up visit, Group A patients were crossed over to concomitant Brinzolamide 1% and Brimonidine 0.2% (Brinz + Brim) therapy while the Group B patients were crossed over to Brinzolamide 1%/brimonidine 0.2% fixed combination (BBFC) therapy. IOP was assessed at baseline and at 6-week and 12-week visits at 9 am (before instillation of drug) and 11 am (post dose, peak effect). The daily cost of both the therapies was calculated by maximum retail price and average drop count per bottle. The cost-effectiveness of both therapies was then calculated as cost of therapy/mm Hg fall in IOP.Results: There was no statistically significant difference between the patient characteristics of the two groups. The mean age for Group A was 64.15 years and for Group B was 63.45 years. In Group A, 10 (50%) were females and in Group B, 11 (55%) were females. There was no statistical difference between the baseline IOP of both the groups. At both time points, IOP lowering from baseline after 6 weeks of therapy with either BBFC or Brinz + Brim was statistically significant (p < 0.00001). After 6 weeks, the mean IOP reduction from baseline in Group A (BBFC) was calculated to be 7.98 ± 1.31 mmHg (31.11%) and for Group B (Brinz + Brim) was calculated to be 7.87 ± 0.98 mmHg (30.56%). The difference in mean IOP reduction between both the groups at 6 weeks was statistically insignificant (p = 0.39). After 6 weeks visit when the therapies were switched among both groups, the mean IOP at the 12-week visit was statistically similar to the mean IOP of the same group at 6 weeks visit. The side effect profile of both the therapies was similar, none of the patients having any serious side effect warranting discontinuation of the treatment. For 6-week study period, cost per mm Hg IOP reduction for BBFC therapy and Brinz + Brim therapy was respectively found to be Rs 45.7 ± 0.4 per mmHg and Rs 67.54 ± 0.29/mmHg per mmHg. The total 6-weekly cost of BBFC therapy was found to be Rs 364.72 ± 3.15 ($ 4.2) while that of Brinz + Brim therapy was Rs 531.55 ± 2.33 ($ 7.43). Using cost minimization analysis, it was found that Brinz + Brim therapy costs Rs 166.83 ± 3.27 ($ 2.63) more than BBFC therapy to attain similar IOP reduction for a period of 6 weeks.
Conclusion:Brinzolam...