Cost-effectiveness analysis of roflumilast/tiotropium therapy versus tiotropium monotherapy for treating severe-to-very severe COPD

Abstract

Objective:

To conduct a cost-effectiveness analysis comparing roflumilast/tiotropium therapy vs tiotropium monotherapy in patients with severe-to-very severe COPD.

Methods:

The economic evaluation applied a disease-based Markov cohort model with five health states: (1) severe COPD, (2) severe COPD with a history of severe exacerbation, (3) very severe COPD, (4) very severe COPD with a history of severe exacerbation, and (5) death. Within a given health state, a patient may have a mild/moderate or severe exacerbation or die. Data from roflumilast clinical trials and published literature were used to populate model parameters. The model calculated health outcomes and costs for roflumilast/tiotropium therapy vs tiotropium monotherapy over a 5-year horizon. Incremental cost and benefits were then calculated as cost-effectiveness ratios, including cost per exacerbation avoided and cost per quality adjusted life year ($/QALY).

Results:

Over a 5-year horizon, the estimated incremental costs per exacerbation and per severe exacerbation avoided were $589 and $5869, respectively, and the incremental cost per QALY was $15,815. One-way sensitivity analyses varying key parameters produced an incremental cost per QALY ranging from $1963–$32,773.

Limitations:

A number of key parameters used in the model were obtained from studies in the literature that were conducted under different contexts. Specifically, the relative risk estimate for severe COPD patients originates from a small trial not designed to demonstrate the impact of roflumilast on frequency of exacerbations. In addition, the model extrapolates the relative risk estimates over periods of 5–30 years, even though the estimates were only observed in trials that spanned less than a year.

Conclusions:

The addition of roflumilast to tiotropium is cost-effective for the treatment of severe to very severe COPD patients.     

Cost effectiveness of tiotropium for chronic obstructive pulmonary disease: a systematic review of the evidence

Abstract

Background:

Tiotropium has been shown to reduce exacerbations and improve quality of life for patients with chronic obstructive pulmonary disease (COPD), a lung disease characterized by a persistent and progressive airflow limitation.

Objectives:

To present a systematic literature review of the cost effectiveness of treatment with tiotropium compared with other currently used treatments for COPD.

Methods:

A systematic search was performed via PubMed, the Cochrane database, and EMBASE from 2002 to 2009. Methods and results by study design and by country were compared.

Results:

Seventeen studies were included in the review. Study designs were characterized as follows: modeling based on clinical trial data, and empirical analysis based on either clinical trial or observational data. Comparing monotherapy regimens (12 studies), all study designs found that treatment with tiotropium was associated with lower costs for hospitalisation and other non-drug services. Total costs, including the costs of maintenance drugs, were lower with tiotropium in some, but not all, of the studies. Tiotropium was shown to be cost effective based on commonly accepted benchmark values. Limitations of the review included the wide variety of outcome measures used in different studies, the limited number of observational database studies for monotherapy, and limited data for combination therapy regimens.

Conclusions:

The main conclusions of the economic evaluations derived from clinical trial data at the time of product approval and from later observational data reflecting clinical use are similar: use of tiotropium monotherapy is associated with lower hospital and other non-drug costs and better health outcomes and is either cost saving or cost effective compared with other maintenance monotherapies.