Cost effectiveness of rimonabant use in patients at increased cardiometabolic risk: estimates from a Markov model

Summary

Rimonabant, the first selective CB-1 receptor blocker, is expected to reduce cardiometabolic risk substantially. This study assesses the economics of such treatment in patients at elevated cardiometabolic risk.

A Markov model was developed using data from the Rimonabant in Obesity (RIO) trial, published risk equations, and UK cost and utility data. Patients begin either in a diabetic or a non-diabetic state and can transition to cardiovascular disease or to death (based on UK life tables). Transitions to diabetes and subsequent cardiovascular events are also counted. Resource use due to events and long-term management were translated to UK costs (2005 GBP). Tariffs for events and states were applied to age-dependent utilities. Extensive univariate and multivariate probabilistic sensitivity analyses were carried out.

Over 10 years, 8% will suffer a cardiovascular event with a loss of more than 1,000 quality-adjusted life years (QALYs) and a cost of more than £500,000 per 1,000 patients. Projecting risk for a lifetime, 1 year of rimonabant use is estimated to gain >65 QALYs at £8,574/QALY. In probabilistic sensitivity analysis, incremental cost-effectiveness ratios varied from £2,657 to £22,141/QALY.

Based on the metabolic effects seen in clinical trials, rimonabant should reduce cardiovascular risk in obese or overweight people at reasonable cost.