Biosimilar Monotherapy Sequence for RA Can Be Considered Cost-Effective, Study Finds

Rheumatoid arthritis (RA) has a considerable economic burden, and costly biologics, are often restricted to cases in which patients fail to respond adequately to methotrexate or other conventional disease-modifying antirheumatic drugs (DMARDS), which may be difficult for some patients to tolerate.

Among those who do initiate biologic treatment, a high rate of inadequate response among those with RA can lead to cycling through different therapies, which is a strategy that has raised concerns about cost-effectiveness; cycling through anti—tumor necrosis factor agents has been found to be particularly costly, especially with respect to non-medication costs for patients with a poor response. Switching to biologics with different mechanisms of action has been shown in some cases to reduce cost, however.

Lower-cost biosimilars, which are beginning to become available to US patients, may provide an opportunity to sequence biologic treatments for patients with RA in a manner that both reduces costs and allows patients to avoid the potential tolerability concerns of DMARDS like methotrexate.

A study presented at the ISPOR 2019 annual meeting sought to evaluate the cost effectiveness of sequencing treatment for adults with moderate to severe RA with biosimilar monotherapy, instead of with DMARDS, from the US payer perspective.¹

Using a cost-utility analysis, a hypothetical cohort-based model was developed, and patients transitioned through a treatment sequence. Health-related quality of life and costs were evaluated across patients’ lifetimes. The model compared a sequence of biosimilars that started with adalimumab, then moved to etanercept, tocilizumab (for which there is no biosimilar yet approved in the United States), and palliative therapy as an alternative to conventional DMARD therapy.

The model used a 6-month cycle of first-line therapy, after which response to treatment was assessed using American College of Rheumatology (ACR) criteria. The proportion of patients with different levels of ACR response was derived from a network meta-analysis.

Costs for treatment were derived from an online formulary tool, and administration, monitoring, and adverse event-related costs were included. Biosimilars were assumed to have 20% discounts to their reference drugs.

The study found that, for patients who used biosimilars, total lifetime costs were $185,002, and the quality-adjusted life years (QALY) gained were 11.63 per patient. The incremental cost-effectiveness ratio was estimated to be $64,720 per QALY gained in the base case analysis, and the probability to be cost-effective through a willingness-to-pay threshold of $50,000 was 13.0%.

The study’s author concluded that sequential monotherapy with biosimilars can be considered cost-effective as an alternative to conventional therapy from the US payer perspective.

Reference

1. Oh M. Cost effectiveness of sequenced treatment of biosimilar targeted immune modulators in moderate to severe rheumatoid arthritis. Presented at: International Society for Pharmacoeconomics and Outcomes Research 24th Annual International Meeting; May 18-22, 2019; New Orleans, Louisiana. Abstract PBI11.