To estimate the cost effectiveness (from the UK NHS and personal social service perspectives) of infliximab plus methotrexate (MTX) compared with MTX alone, in the treatment of patients with severe rheumatoid arthritis (RA) who were not adequately controlled on disease-modifying antirheumatic drugs and who were resistant to MTX.
Clinical data for the first year of therapy were taken from the ATTRACT (Anti-Tumour Necrosis Factor Trial in Rheumatoid Arthritis with Concomitant Therapy) and a Markov model developed to assess costs and consequences in the longer term. Transition probabilities and health state valuations for the model were estimated based on the ARAMIS (Arthritis, Rheumatism, and Aging Medical Information System) cohort, and resource use and costs ( 2,000 pounds values) obtained from various sources in the UK. Univariate sensitivity analyses were conducted to test the robustness of the results.
The primary analysis suggested that infliximab plus MTX had an ICER of 33,618 pounds per QALY gained. Alternative modelling assumptions and various other sensitivity analyses were applied, but the ICER always remained within the range for interventions typically funded by the NHS.
This model suggests, with its underlying assumptions and data, that the combination of infliximab and MTX may be a cost-effective treatment (from the UK NHS and personal social service perspectives) for patients experiencing RA that cannot be maintained on MTX alone.