title: [Cost-per-responder analysis comparing romiplostim to rituximab in the treatment of adult primary immune thrombocytopenia in Spain].
abstract: OBJECTIVE
  Romiplostim, a thrombopoietin-receptor agonist, is approved for second-line use in idiopathic thrombocytopenic purpura (ITP) patients where surgery is contraindicated. Anti-CD20 rituximab, an immunosuppressant, is currently used off-label. This analysis compared the cost per responder for romiplostim versus rituximab in Spain.
  
  
  METHODS
  A decision analytic model was constructed to estimate the 6-month cost per responding patient (achieving a platelet count≥50×10(9)/l) according to the most robust published data. A systematic literature review was performed to extract response rates from phase 3 randomized controlled trials. Romiplostim patients received weekly injections; rituximab patients received 4 weekly intravenous infusions. Medical resource costs were obtained from Spanish reimbursement lists. Treatment non-responders incurred bleeding-related event (BRE) management costs as reported in clinical trials. Medical resource utilization and clinical practice were based on Spanish treatment guidelines and validated by local clinical experts.
  
  
  RESULTS
  The literature review identified phase 3 romiplostim trials with a response rate of 83%. Due to a lack of phase 3 controlled rituximab trials, a systematic review of studies was selected as the best source, reporting a response rate of 62.5%. The mean cost per patient for romiplostim was €16,289 and €13,459 for rituximab. Rituximab resulted in a 10% higher cost per responder (€21,535 versus €19,625 for romiplostim). Romiplostim use reduced drug administration, intravenous immunoglobulin, and bleeding-related costs compared to rituximab.
  
  
  CONCLUSIONS
  Due to its high level of efficacy leading to lower BRE costs, romiplostim represents an efficient use of resources for adult ITP patients in the Spanish Healthcare System.
authors.affiliation: Complejo Hospitalario Universitario de A Coruña, A Coruña, España.
authors.forename: M Fernanda
authors.initials: MF
authors.lastname: López
authors.affiliation: Hospital Regional Universitario Carlos Haya, Málaga, España.
authors.forename: María Eva
authors.initials: ME
authors.lastname: Mingot
authors.affiliation: Hospital Vall d́Hebrón, Barcelona, España.
authors.forename: David
authors.initials: D
authors.lastname: Valcárcel
authors.affiliation: Hospital Universitario Morales Meseguer, Murcia, España.
authors.forename: Vicente
authors.initials: V
authors.lastname: Vicente García
authors.affiliation: LA-SER Analytica, Nueva York, Estados Unidos.
authors.forename: Allison
authors.initials: A
authors.lastname: Perrin
authors.affiliation: Global Health Economics, Amgen (Europe) GmbH, Zug, Suiza. Electronic address: ignasic@amgen.com.
authors.forename: Ignasi
authors.initials: I
authors.lastname: Campos Tapias
mesh_terms: D000328:Adult; D003365:Costs and Cost Analysis; D003663:Decision Trees; D006801:Humans; D007155:Immunologic Factors / Q000191:economics* / Q000627:therapeutic use*; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000188:drug therapy* / Q000191:economics*; D011961:Receptors, Fc / Q000627:therapeutic use*; D053628:Receptors, Thrombopoietin / Q000819:agonists*; D011993:Recombinant Fusion Proteins / Q000191:economics* / Q000627:therapeutic use*; D000069283:Rituximab / Q000191:economics* / Q000627:therapeutic use*; D013030:Spain; D013926:Thrombopoietin / Q000191:economics* / Q000627:therapeutic use*
chemical_list: D007155:Immunologic Factors; D011961:Receptors, Fc; D053628:Receptors, Thrombopoietin; D011993:Recombinant Fusion Proteins; D000069283:Rituximab; D013926:Thrombopoietin; C488777:romiplostim
keywords: Costes y análisis de costes; Costs and costs analysis; Idiopathic thrombocytopenic purpura; Púrpura trombocitopénica idiopática; Rituximab; Romiplostim