OBJECTIVES: Tofacitinib (TFC) is an oral Janus kinase inhibitor for the treatment of moderately to severely active rheumatoid arthritis (RA). This study was aimed to estimate the cost-effectiveness of tofacitinib versus adalimumab (ADA) from a payer perspective in RA patients for whom with inadequate response or intolerance to methotrexate (MTX) in Iran.

METHODS: A cohort-based Markov model was developed using TreeAge pro 2018 to evaluate the lifetime cost-effectiveness of TFC (5 mg twice a day) plus MTX versus ADA (40 mg every other week) plus MTX using efficacy results from a phase 3b/4 head-to-head study (ORAL Strategy). Response to treatment was modeled as American College of Rheumatology (ACR) 20/50/70 response. ACR responses produce changes in the Health Assessment Questionnaire-Disability Index (HAQ-DI) score. To estimate quality-adjusted life-years (QALYs), the HAQ-DI score was mapped to utility. Costs were reported in 2018 U.S. dollars and comprised medications, hospitalization, outpatient visits, administration, dispensing, monitoring, palliative therapy, and treatment for adverse events. Cost-effectiveness result was presented in terms of incremental cost-effectiveness ratio (ICER). One-way and probabilistic sensitivity analyses (PSA) were conducted to explore the uncertainty of model parameters and assumptions.

RESULTS: TFC compared to ADA was associated with higher cost (US$ 29,506 vs US$ 29,340) and higher efficacy (6.05 QALYs vs 5.99 QALYs) throughout the lifetime of patients with RA and MTX inadequate response, resulting in an ICER of US$ 2,618 per QALY. One-way sensitivity analysis indicated that the result is sensitive to TFC and ADA acquisition cost. PSA demonstrated that TFC had a 57% probability of being cost effective at the willingness to pay threshold of Iran 1 GDP/capita (US$ 5400) compared to ADA.

CONCLUSIONS: TFC is projected to be cost-effective compared to ADA in patients with moderate to severe RA for whom methotrexate is not appropriate, from Iranian payer perspective.