Indirect cost-effectiveness analyses of abatacept and rituximab in patients with moderate-to-severe rheumatoid arthritis in the United States.
OBJECTIVE
To estimate the incremental cost per quality-adjusted life-years (QALYs) for abatacept and rituximab, in combination with methotrexate, relative to methotrexate alone in patients with active rheumatoid arthritis (RA).


METHODS
A patient-level simulation model was used to depict the progression of functional disability over the lifetimes of women aged 55-64 years with active RA and inadequate response to a tumor necrosis factor (TNF)-alpha antagonist therapy. Future health-state utilities and medical care costs were based on projected values of the Health Assessment Questionnaire Disability Index (HAQ-DI). Patients were assumed to receive abatacept or rituximab in combination with methotrexate until death or therapy discontinuation due to lack of efficacy or adverse events. HAQ-DI improvement at month 6, after adjustments for control drug (methotrexate) response, was derived from two clinical trials. Costs of medical care and biologic drugs, discounted at 3% annually, were from the perspective of a US third-party payer and expressed in 2007 US dollars.


RESULTS
Relative to methotrexate alone, abatacept/methotrexate and rituximab/methotrexate therapies were estimated to yield an average of 1.25 and 1.10 additional QALYs per patient, at mean incremental costs of $58,989 and $60,380, respectively. The incremental cost-utility ratio relative to methotrexate was $47,191 (95% CI $44,810-49,920) per QALY gained for abatacept/methotrexate and $54,891 (95% CI $52,274-58,073) per QALY gained for rituximab/methotrexate. At an acceptability threshold of $50,000 per QALY, the probability of cost effectiveness was 90% for abatacept and 0.0% for rituximab.


CONCLUSIONS
Abatacept was estimated to be more cost effective than rituximab for use in RA from a US third-party payer perspective. However, head-to-head clinical trials and long-term observational data are needed to confirm these findings.
Yuan
Yong
Y
Health Economics and Outcomes Research, Bristol-Myers Squibb, 777 Scudders Mill Road, Plainsboro, NJ 08536, USA. yong.yuan@bms.com
Trivedi
Digisha
D
Maclean
Ross
R
Rosenblatt
Lisa
L
D000069594:Abatacept; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D058846:Antibodies, Monoclonal, Murine-Derived / Q000191:economics* / Q000627:therapeutic use; D018501:Antirheumatic Agents / Q000191:economics* / Q000627:therapeutic use; D003362:Cost-Benefit Analysis; D004185:Disability Evaluation; D005260:Female; D006305:Health Status Indicators; D006801:Humans; D018796:Immunoconjugates / Q000191:economics* / Q000627:therapeutic use; D007155:Immunologic Factors / Q000191:economics* / Q000627:therapeutic use; D008727:Methotrexate / Q000191:economics* / Q000627:therapeutic use; D008875:Middle Aged; D009010:Monte Carlo Method; D019057:Quality-Adjusted Life Years; D012213:Rheumatic Fever / Q000188:drug therapy / Q000191:economics* / Q000473:pathology; D000069283:Rituximab; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors; D014481:United States; D055815:Young Adult
D058846:Antibodies, Monoclonal, Murine-Derived; D018501:Antirheumatic Agents; D018796:Immunoconjugates; D007155:Immunologic Factors; D014409:Tumor Necrosis Factor-alpha; D000069283:Rituximab; D000069594:Abatacept; D008727:Methotrexate