title: Real world costs and cost-effectiveness of Rituximab for diffuse large B-cell lymphoma patients: a population-based analysis.
abstract: BACKGROUND
  Current treatment of diffuse-large-B-cell lymphoma (DLBCL) includes rituximab, an expensive drug, combined with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) chemotherapy. Economic models have predicted rituximab plus CHOP (RCHOP) to be a cost-effective alternative to CHOP alone as first-line treatment of DLBCL, but it remains unclear what its real-world costs and cost-effectiveness are in routine clinical practice.
  
  
  METHODS
  We performed a population-based retrospective cohort study from 1997 to 2007, using linked administrative databases in Ontario, Canada, to evaluate the costs and cost-effectiveness of RCHOP compared to CHOP alone. A historical control cohort (n = 1,099) with DLBCL who received CHOP before rituximab approval was hard-matched on age and treatment intensity and then propensity-score matched on sex, comorbidity, and histology to 1,099 RCHOP patients. All costs and outcomes were adjusted for censoring using the inverse probability weighting method. The main outcome measure was incremental cost per life-year gained (LYG).
  
  
  RESULTS
  Rituximab was associated with a life expectancy increase of 3.2 months over 5 years at an additional cost of $16,298, corresponding to an incremental cost-effectiveness ratio of $61,984 (95% CI $34,087-$135,890) per LYG. The probability of being cost-effective was 90% if the willingness-to-pay threshold was $100,000/LYG. The cost-effectiveness ratio was most favourable for patients less than 60 years old ($31,800/LYG) but increased to $80,600/LYG for patients 60-79 years old and $110,100/LYG for patients ≥ 80 years old. We found that post-market survival benefits of rituximab are similar to or lower than those reported in clinical trials, while the costs, incremental costs and cost-effectiveness ratios are higher than in published economic models and differ by age.
  
  
  CONCLUSIONS
  Our results showed that the addition of rituximab to standard CHOP chemotherapy was associated with improvement in survival but at a higher cost, and was potentially cost-effective by standard thresholds for patients <60 years old. However, cost-effectiveness decreased significantly with age, suggesting that rituximab may be not as economically attractive in the very elderly on average. This has important clinical implications regarding age-related use and funding decisions on this drug.
authors.forename: Sara
authors.initials: S
authors.lastname: Khor
authors.forename: Jaclyn
authors.initials: J
authors.lastname: Beca
authors.forename: Murray
authors.initials: M
authors.lastname: Krahn
authors.forename: David
authors.initials: D
authors.lastname: Hodgson
authors.forename: Linda
authors.initials: L
authors.lastname: Lee
authors.forename: Michael
authors.initials: M
authors.lastname: Crump
authors.forename: Karen E
authors.initials: KE
authors.lastname: Bremner
authors.forename: Jin
authors.initials: J
authors.lastname: Luo
authors.forename: Muhammad
authors.initials: M
authors.lastname: Mamdani
authors.forename: Chaim M
authors.initials: CM
authors.lastname: Bell
authors.forename: Carol
authors.initials: C
authors.lastname: Sawka
authors.forename: Scott
authors.initials: S
authors.lastname: Gavura
authors.forename: Terrence
authors.initials: T
authors.lastname: Sullivan
authors.forename: Maureen
authors.initials: M
authors.lastname: Trudeau
authors.forename: Stuart
authors.initials: S
authors.lastname: Peacock
authors.affiliation: Pharmacoeconomics Research Unit, Cancer Care Ontario, Toronto, Canada. Jeffrey.hoch@utoronto.ca.
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Hoch
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D058846:Antibodies, Monoclonal, Murine-Derived / Q000191:economics* / Q000627:therapeutic use; D000970:Antineoplastic Agents / Q000191:economics* / Q000627:therapeutic use; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000191:economics* / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D003362:Cost-Benefit Analysis; D005260:Female; D006801:Humans; D007223:Infant; D016403:Lymphoma, Large B-Cell, Diffuse / Q000188:drug therapy* / Q000191:economics / Q000401:mortality; D008297:Male; D008875:Middle Aged; D018803:Models, Economic; D009864:Ontario; D000069283:Rituximab; D015996:Survival Rate; D055815:Young Adult
chemical_list: D058846:Antibodies, Monoclonal, Murine-Derived; D000970:Antineoplastic Agents; D000069283:Rituximab