A pharmacoeconomic evaluation of results from the coronary angioplasty amlodipine restenosis study (CAPARES) in Norway and Canada

Introduction: The objective of this analysis was to evaluate the health economic benefits of using amlodipine in patients undergoing angioplasty procedures in Canada and Norway. Methods: A decision tree model was constructed to find the total expected cost per patient for a 4-month time period following an initial angioplasty. The model used clinical data from the Coronary Angioplasty Amlodipine Restenosis Study (CAPARES), a prospective, randomized, double blind, placebo-controlled trial conducted to investigate the effects of amlodipine on restenosis and clinical events in patients undergoing percutaneous transluminal coronary angioplasty (PTCA). Outcomes of interest to this analysis included MI, repeat PTCA, CABG, and all-cause mortality. Clinical experts from Canada and Norway were enlisted and a modified Delphi study approach was used to quantify healthcare resources consumed for each clinical outcome. Results: The use of amlodipine decreased the rates of MI, PTCA, and CABG by 2.0, 4.7, and 2.7%, respectively. The total expected cost per patient using amlodipine was $6,398.30 (US$4,323) in Canada and kr 59,993.27 (US$6,846) in Norway. The total expected cost per patient not using amlodipine was $6,519.37 (US$4,405) in Canada and kr 64,292.17 (US$7,337) in Norway. The model demonstrated potential cost-savings over a 4-month follow up period resulting from the improved clinical outcomes for patients using amlodipine with PTCA—$121,071 (US$81,844) per 1000 patients in Canada and kr 4,298,899 (US$490,074) per 1000 patients in Norway. Conclusions: The adjunctive use of amlodipine is a cost-effective therapeutic strategy to achieve more favorable clinical outcomes in patients undergoing PTCAs in Canada and Norway.