title: Economic evaluation of obinutuzumab in combination with chlorambucil in first-line treatment of patients with chronic lymphocytic leukemia in Spain.
abstract: OBJECTIVE
  To evaluate the cost-effectiveness of obinutuzumab in combination with chlorambucil (GClb) versus rituximab plus chlorambucil (RClb) in the treatment of adults with previously untreated chronic lymphocytic leukemia (CLL) and with comorbidities that make them unsuitable for full-dose fludarabine-based therapy, from the perspective of the Spanish National Health System.
  
  
  METHODS
  A Markov model was developed with three mutually exclusive health states: progression-free survival (with or without treatment), progression, and death. Survival time for the two treatments was modeled based on the results of CLL11 clinical trial and external sources. Each health state was associated with a utility value and direct medical costs. The utilities were obtained from a utility elicitation study conducted in the UK. Costs and general background mortality data were obtained from published Spanish sources. Deterministic and probabilistic analyses were conducted, with a time frame of 20 years. The health outcomes were measured as life years (LYs) gained and quality-adjusted life years (QALYs) gained. Efficiency was measured as the cost per LY or per QALY gained of the most effective regimen.
  
  
  RESULTS
  In the deterministic base case analysis, each patient treated with GClb resulted in 0.717 LYs gained and 0.673 QALYs gained versus RClb. The cost per LY and per QALY gained with GClb versus RClb was €23,314 and €24,838, respectively. The results proved stable in most of the univariate and probabilistic sensitivity analyses, with a probabilistic cost per QALY gained of €24,734 (95% confidence interval: €21,860-28,367).
  
  
  CONCLUSIONS
  Using GClb to treat patients with previously untreated CLL for whom full-dose fludarabine-based therapy is unsuitable allows significant gains in terms of LYs and QALYs versus treatment with RClb. Treatment with GClb versus RClb can be regarded as efficient when considered the willingness to pay thresholds commonly used in Spain.
authors.affiliation: Hematology Department, Hospital Virgen de la Salud, Toledo, Spain.
authors.forename: Luis Felipe
authors.initials: LF
authors.lastname: Casado
authors.affiliation: Pharmacy Department, Hospital General Universitario de Alicante, Alicante, Spain.
authors.forename: Amparo
authors.initials: A
authors.lastname: Burgos
authors.affiliation: Pharmacy Department, Hospital Universitario Gregorio Marañón, Madrid, Spain.
authors.forename: Eva
authors.initials: E
authors.lastname: González-Haba
authors.affiliation: Hematology Deparment, Hospital Universitario De La Princesa, Madrid, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Loscertales
authors.affiliation: Hoffmann-La Roche Ltd., Basel, Switzerland.
authors.forename: Tania
authors.initials: T
authors.lastname: Krivasi
authors.affiliation: Roche Farma SA, Madrid, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Orofino
authors.affiliation: Health Value, Madrid, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: Rubio-Terres
authors.affiliation: Health Value, Madrid, Spain.
authors.forename: Darío
authors.initials: D
authors.lastname: Rubio-Rodríguez
keywords: chlorambucil; chronic lymphocytic leukemia; cost-effectiveness; obinutuzumab; rituximab