Pharmacoeconomic analysis of valsartan for the treatment of chronic congestive heart failure in Italy

Abstract

Objective: to evaluate pharmacoeconomic implications of the use of valsartan, an angiotensin II antagonist in addition to standard therapy for the treatment of chronic congestive heart failure (CHF). Methods: the study was conducted performing cost-utility and budget impact (B.I.) analyses by means of a cohort simulation based on a probabilistic Markov model and projecting 23-months follow-up results in the Val-HeFT trial study over a 10-years time horizon. The model included four states (class NYHA I, II and III and death), and had a cycle of 1 year. Two probabilistic simulations (varying first patients parameters and after model parameters) were performed using WinBUGS, a software for bayesian analysis. The distributions of patients parameters (sex, age, use of ACE inhibitors) corresponding to Val-HeFT inclusion criteria in the simulated population were derived from the Italian CHF patients population. Individual mortality was derived from general mortality by adjusting with a NYHA state-specific HR, and the probability of changing NYHA class from Val-HeFT. Costs were calculated in the perspective of the Italian NHS and account for drugs and CHF hospitalizations. Quality of life weights were obtained by elaborating published HRQoL data of CHF patients. A 3.5% annual discount rate was applied; probabilistic sensitivity analysis was performed on each parameter using original-source 95% CI, or a ±10% range where it was unavailable. Results: in the 10 years horizon, patients were estimated to live an average of 4.4 years or 3.2 QALYs, with slight increases in the valsartan group. In this group, hospitalizations are predicted to be sensitively reduced and overall costs decreased by about 500 €/pz. In subgroup analysis, valsartan loses dominance in NYHAII and ACE-using patients, for which ICURs are 17,330 and 27,000 €/QALY, respectively. B.I. analysis predicts a saving of about 172 millions €. Conclusions: valsartan in addition to standard therapy is predicted to be a cost/effective strategy for Italian patients with mild-to-severe CHF and cost-saving from the perspective of the NHS.