Estimating the cost-effectiveness of 54 weeks of infliximab for rheumatoid arthritis.
OBJECTIVE
To estimate the cost-effectiveness of infliximab plus methotrexate for active, refractory rheumatoid arthritis.


METHODS
We projected the 54-week results from a randomized controlled trial of infliximab into lifetime economic and clinical outcomes using a Markov computer simulation model. Direct and indirect costs, quality of life, and disability estimates were based on trial results; Arthritis, Rheumatism, and Aging Medical Information System (ARAMIS) database outcomes; and published data. Results were discounted using the standard 3% rate. Because most well-accepted medical therapies have cost-effectiveness ratios below $50,000 to $100,000 per quality-adjusted life-year (QALY) gained, results below this range were considered to be "cost-effective."


RESULTS
At 3 mg/kg, each infliximab infusion would cost $1393. When compared with methotrexate alone, 54 weeks of infliximab plus methotrexate decreased the likelihood of having advanced disability from 23% to 11% at the end of 54 weeks, which projected to a lifetime marginal cost-effectiveness ratio of $30,500 per discounted QALY gained, considering only direct medical costs. When applying a societal perspective and including indirect or productivity costs, the marginal cost-effectiveness ratio for infliximab was $9100 per discounted QALY gained. The results remained relatively unchanged with variation of model estimates over a broad range of values.


CONCLUSIONS
Infliximab plus methotrexate for 54 weeks for rheumatoid arthritis should be cost-effective with its clinical benefit providing good value for the drug cost, especially when including productivity losses. Although infliximab beyond 54 weeks will likely be cost-effective, the economic and clinical benefit remains uncertain and will depend on long-term results of clinical trials.
Wong
John B
JB
Division of Clinical Decision Making, Department of Medicine, Tupper Research Institute, Tufts-New England Medical Center, Tufts University School of Medicine, Boston, Massachusetts 02111, USA. jwong@lifespan.org
Singh
Gurkirpal
G
Kavanaugh
Arthur
A
D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal / Q000008:administration & dosage / Q000191:economics* / Q000627:therapeutic use*; D018501:Antirheumatic Agents / Q000008:administration & dosage / Q000191:economics* / Q000627:therapeutic use*; D001172:Arthritis, Rheumatoid / Q000188:drug therapy* / Q000191:economics*; D003362:Cost-Benefit Analysis; D016527:Drug Costs; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D000069285:Infliximab; D008297:Male; D008390:Markov Chains; D008727:Methotrexate / Q000008:administration & dosage / Q000191:economics / Q000627:therapeutic use; D008875:Middle Aged; D019057:Quality-Adjusted Life Years; D013997:Time Factors; D016896:Treatment Outcome
D000911:Antibodies, Monoclonal; D018501:Antirheumatic Agents; D000069285:Infliximab; D008727:Methotrexate