An adherence based cost-consequence model comparing bimatoprost 0.01% to bimatoprost 0.03%

Current Knowledge and Attitudes Concerning Cost-Effectiveness in Glaucoma Pharmacotherapy: A Glaucoma Specialists Focus Group Study

Background

Rising healthcare costs motivate continued cost-reduction efforts. To help lower costs associated with open-angle glaucoma (OAG), a prevalent, progressive disease with substantial direct and indirect costs, clinicians need to understand the cost-effectiveness of intraocular pressure (IOP)-lowering pharmacotherapies. There is little published information on clinicians’ knowledge and attitudes about cost-effectiveness in glaucoma treatment.

Purpose

This pilot focus group study aimed to explore clinician attitudes and perspectives around the costs and cost drivers of glaucoma therapy; the implementation of cost-effectiveness decisions; the clinical utility of cost-effectiveness studies; and the cost-effectiveness of available treatments.

Methods

Six US glaucoma specialists participated in two separate teleconferencing sessions (three participants each), managed by an independent, skilled moderator (also a glaucoma specialist) using a discussion guide. Participants reviewed recent publications (n=25) on health economics outcomes research in glaucoma prior to the sessions.

Results

Participants demonstrated a clear understanding of the economic burden of glaucoma therapy and identified medications, diagnostics, office visits, and treatment changes as key cost drivers. They considered cost-effectiveness an appropriate component of treatment decision-making but identified the need for additional data to inform these decisions. Participants indicated that there were only a few recent studies on health economics outcomes in glaucoma which evaluate parameters important to patient care, such as quality of life and medication adherence, and that longitudinal data were scant. In addition to efficacy, participants felt patient adherence and side-effect profile should be included in economic evaluations of glaucoma pharmacotherapy. Recently approved medications were evaluated in this context.

Conclusion

Clinicians deem treatment decisions based on cost-effectiveness data as clinically appropriate. Newer IOP-lowering therapies with potentially greater efficacy and favorable side-effect and adherence profiles may help optimize cost-effectiveness. Future studies should include: clinicians’ perspectives; lack of commercial bias; analysis of long-term outcomes/costs; more comprehensive parameters; real-world (including quality-of-life) data; and a robust Markov model.

Evaluating intraocular pressure-lowering solutions for the treatment of open-angle glaucoma: comparison between bimatoprost 0.03% and bimatoprost 0.01% - an observational switch study

PURPOSE

The purpose of this study is to evaluate the intraocular pressure (IOP)-lowering efficacy of bimatoprost 0.01% solution in patients with primary open-angle glaucoma (POAG), who were switched from bimatoprost 0.03% solution, compared to patients with POAG who continued on bimatoprost 0.03% solution.

METHODS

A retrospective review evaluated 35 patients (35 right eyes [OD], 34 left eyes [OS]) who remained on bimatoprost 0.03% and 30 patients (27 OD, 30 OS) who were switched to bimatoprost 0.01% during the period January 8, 2010 to December 26, 2012. Mean IOP was measured 6 and 3 months before the switch, at switch, and 3, 6, and 12 months after the switch. Hyperemia scores were recorded before and after the switch and were compared to a picture scale.

RESULTS

Mean IOP in the group that switched was 16.96±5.03 mmHg in OD and 17.67±5.33 mmHg in OS at baseline. Mean IOP postswitch to bimatoprost 0.01% solution was 17.60±4.34 mmHg in OD and 17.00±3.37 mmHg in OS. IOP was not significantly reduced in either OD or OS postswitch to bimatoprost 0.01% (P₁=0.5 OD, P₂=0.2 OS). The hyperemia scores improved remarkably when bimatoprost 0.03% solution was switched to bimatoprost 0.01% solution (P<0.001).

CONCLUSION

To our knowledge, this is the first switch study evaluating the hypotensive efficacy and tolerability of bimatoprost in a group of patients with open-angle glaucoma. In this study comparing bimatoprost 0.03% and 0.01% solution, we found improved tolerability postswitch to 0.01% from 0.03% bimatoprost, similar efficacy between the two concentrations before and after switch in the same patient population, and similar IOPs comparable to nonswitch bimatoprost 0.03% solution.