ClinicoEconomics and Outcomes Research (Dec 2016)
Cost-effectiveness analysis of combination antifungal therapy with voriconazole and anidulafungin versus voriconazole monotherapy for primary treatment of invasive aspergillosis in Spain
Abstract
Santiago Grau,1 Jose Ramon Azanza,2 Isabel Ruiz,3 Carlos Vallejo,4 Josep Mensa,5 Johan Maertens,6 Werner J Heinz,7 Jon Andoni Barrueta,8 Carmen Peral,9 Francisco Jesús Mesa,8 Miguel Barrado,10 Claudie Charbonneau,11 Darío Rubio-Rodríguez,12 Carlos Rubio-Terrés12 1Pharmacy Department, Hospital del Mar, Universitat Autònoma de Barcelona, Barcelona, 2Clinical Pharmacology Department, Clínica Universidad de Navarra, Pamplona, 3Infectious Diseases Department, Hospital Universitari Vall d’Hebron, Barcelona, 4Hematology Department, Hospital Universitario Donostia, San Sebastián, 5Infectious Diseases Department, Hospital Clínic de Barcelona, Barcelona, Spain; 6Hematology Department, University Hospital Gasthuisberg, Leuven, Belgium; 7Hematology/Oncology Department, Medizinische Klinik und Poliklinik II, Universitätsklinikum, Würzburg, Germany; 8Medical Department, 9Economics and Outcomes Research Department, Pfizer S.L.U, Alcobendas, 10Clinical Trials Department, Trial Form Support, Madrid, Spain; 11Pharmacoeconomics Department, Pfizer International Operations, Paris, France; 12Pharmacoeconomics Department, Health Value, Madrid, Spain Objective: According to a recent randomized, double-blind clinical trial comparing the combination of voriconazole and anidulafungin (VOR+ANI) with VOR monotherapy for invasive aspergillosis (IA) in patients with hematologic disease or with hematopoietic stem cell transplant, mortality was lower after 6 weeks with VOR+ANI than with VOR monotherapy in a post hoc analysis of patients with galactomannan-based IA. The objective of this study was to compare the cost-effectiveness of VOR+ANI with VOR, from the perspective of hospitals in the Spanish National Health System.Methods: An economic model with deterministic and probabilistic analyses was used to determine costs per life-year gained (LYG) for VOR+ANI versus VOR in patients with galactomannan-based IA. Mortality, adverse event rates, and life expectancy were obtained from clinical trial data. The costs (in 2015 euros [€]) of the drugs and the adverse event-related costs were obtained from Spanish sources. A Tornado plot and a Monte Carlo simulation (1,000 iterations) were used to assess uncertainty of all model variables.Results: According to the deterministic analysis, for each patient treated with VOR+ANI compared with VOR monotherapy, there would be a total of 0.348 LYG (2.529 vs 2.181 years, respectively) at an incremental cost of €5,493 (€17,902 vs €12,409, respectively). Consequently, the additional cost per LYG with VOR+ANI compared with VOR would be €15,785. Deterministic sensitivity analyses confirmed the robustness of these findings. In the probabilistic analysis, the cost per LYG with VOR+ANI was €15,774 (95% confidence interval: €15,763–16,692). The probability of VOR+ANI being cost-effective compared with VOR was estimated at 82.5% and 91.9%, based on local cost-effectiveness thresholds of €30,000 and €45,000, respectively.Conclusion: According to the present economic study, combination therapy with VOR+ANI is cost-effective as primary therapy of IA in galactomannan-positive patients in Spain who have hematologic disease or hematopoietic stem cell transplant, compared with VOR monotherapy. Keywords: anidulafungin, cost-effectiveness, galactomannan, invasive aspergillosis, voriconazole