Cost effectiveness of leukotriene receptor antagonists versus long-acting beta-2 agonists as add-on therapy to inhaled corticosteroids for asthma: a pragmatic trial

Abstract

Background: Information is lacking on the relative effectiveness and cost effectiveness--in a real-life primary-care setting--of leukotriene receptor antagonists (LTRAs) and long-acting beta2 adrenergic receptor agonists (beta2 agonists) as add-on therapy for patients whose asthma symptoms are not controlled on low-dose inhaled corticosteroids (ICS).

Objective: To estimate the cost effectiveness of LTRAs compared with long-acting beta2 agonists as add-on therapy for patients whose asthma symptoms are not controlled on low-dose ICS.

Methods: An economic evaluation was conducted alongside a 2-year, pragmatic, randomized controlled trial set in 53 primary-care practices in the UK. Patients aged 12-80 years with asthma insufficiently controlled with ICS (n = 361) were randomly assigned to add-on LTRAs (n = 176) or long-acting beta2 agonists (n = 185). The main outcome measures were the incremental cost per point improvement in the Mini Asthma Quality of Life Questionnaire (MiniAQLQ), per point improvement in the Asthma Control Questionnaire (ACQ) and per QALY gained from perspectives of the UK NHS and society.

Results: Over 2 years, the societal cost per patient receiving LTRAs was pounds sterling 1157 versus pounds sterling 952 for long-acting beta2 agonists, a (significant, adjusted) increase of pounds sterling 214 (95% CI 2, 411) [year 2005 values]. Patients receiving LTRAs experienced a non-significant incremental gain of 0.009 QALYs (95% CI -0.077, 0.103). The incremental cost per QALY gained from the societal (NHS) perspective was pounds sterling 22,589 (pounds sterling 11,919). Uncertainty around this point estimate suggested that, given a maximum willingness to pay of pounds sterling 30,000 per QALY gained, the probability that LTRAs are a cost-effective alternative to long-acting beta2 agonists as add-on therapy was approximately 52% from both societal and NHS perspectives.

Conclusions: On balance, these results marginally favour the repositioning of LTRAs as a cost-effective alternative to long-acting beta2 agonists as add-on therapy to ICS for asthma. However, there is much uncertainty surrounding the incremental cost effectiveness because of similarity of clinical benefit and broad confidence intervals for differences in healthcare costs.

Trial registration: UK National Research Register N0547145240; Controlled Clinical Trials ISRCTN99132811.