Estimating the cost effectiveness of ramipril used for specific clinical indications: comparing the outcomes in four clinical trials with a common economic model.
OBJECTIVE
Economic analyses of drug therapies are highly dependent on the clinical indications for treatment. The cost effectiveness of ramipril has been evaluated in numerous studies, usually based on the results of one specific clinical trial. We estimated the cost effectiveness of this drug across a range of currently accepted therapeutic indications, using a single health economic model and adjusted for quality of life, to compare the different outcomes observed in four clinical trials.


METHODS
The cardiovascular life expectancy model, a validated Markov model, was calibrated to accurately forecast the results of four trials including AIRE, HOPE, Micro-HOPE, and REIN. We then extrapolated these results over the remaining life expectancy of the patients enrolled in each study and adjusted for the quality of life associated with the observed outcomes. The cost per quality-adjusted life-year (QALY) was then calculated from the perspective of the Canadian healthcare system incorporating the estimated direct healthcare costs associated with treatments and outcomes.


RESULTS
After discounting all costs and outcomes 3% annually, the benefits associated with ramipril ranged from 0.74 QALYs in the AIRE study to 1.22 QALYs in Micro-HOPE. Treatment was estimated to be cost-saving for some patient groups, such as those in REIN. The highest cost-effectiveness ratio was observed among individuals enrolled in HOPE ($Can20 000 per QALY in 2002).


CONCLUSIONS
Treatment with ramipril appears to be economically attractive across a wide range of patient groups, including those with increased coronary risk and/or diabetes mellitus (HOPE and Micro-HOPE), those with congestive heart failure (AIRE), and those with non-diabetic nephropathy (REIN).
Grover
Steven A
SA
Department of Medicine and Epidemiology and Biostatistics, The McGill University Health Centre, McGill University, Montreal, Quebec, Canada. steven.grover@mcgill.ca
Coupal
Louis
L
Lowensteyn
Ilka
I
D000806:Angiotensin-Converting Enzyme Inhibitors / Q000191:economics* / Q000627:therapeutic use; D002170:Canada; D002318:Cardiovascular Diseases / Q000188:drug therapy / Q000191:economics*; D002986:Clinical Trials as Topic; D003362:Cost-Benefit Analysis; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy / Q000191:economics*; D005260:Female; D006333:Heart Failure / Q000188:drug therapy / Q000191:economics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018803:Models, Economic; D011507:Proteinuria / Q000188:drug therapy / Q000191:economics*; D011788:Quality of Life; D019057:Quality-Adjusted Life Years; D017257:Ramipril / Q000191:economics* / Q000627:therapeutic use; D016896:Treatment Outcome
D000806:Angiotensin-Converting Enzyme Inhibitors; D017257:Ramipril