Rheumatoid Arthritis: Therapeutic Strategies After Inadequate Response to Initial TNF Inhibitor Therapy

What are recent trends in the use of bDMARDs?

Currently, there are no specific guidelines or biomarkers available to facilitate selection of specific treatment from among the classes of biologics. With the development of several new drugs and regulatory approval of baricitinib, physicians now have several biologic options to treat patients. A recent large time-trend study⁸⁰ deriving data from more than 200,000 patients with RA showed that etanercept remains the most frequently used agent for the treatment of RA; it also showed that the use of adalimumab and infliximab is decreasing, and that the use of newer agents, especially abatacept, golimumab, and certolizumab, has considerably risen in recent years. In this study, abatacept, rituximab, certolizumab, golimumab, tocilizumab, and tofacitinib accounted for 13.2%, 13.8%, 6.9%, 11.9%, and 7.5% switches from first TNFi therapy.

Jin et al⁸¹ studied factors associated with the choice of bDMARD for initial and subsequent use. They found that patients with commercial insurance had an 87% higher likelihood of initiating a bDMARD. In the Medicaid subgroup, African Americans had lower odds of initiating and switching bDMARDs than non-Hispanic whites. Prior use of steroids and nonbiologic DMARDs predicted both bDMARD initiation and subsequent switching. Etanercept, adalimumab, and infliximab were the most commonly used first- and second-line bDMARDS; patients on anakinra and golimumab were most likely to be switched to other bDMARDs.

Which treatment strategy is the most cost-effective?

Several studies have reported better treatment persistence rates among patients who are treated with the swapping strategy compared to the cycling strategy. In a retrospective analysis of claims data,⁸² the authors examined treatment persistence and health care costs in patients switching to biologics with a different mechanism of action or cycling to another TNFi. The mean cost was significantly lower among patients treated using the swapping strategy than among the TNFi cyclers, both for the total cost of care for RA and for the total cost of the targeted DMARDs in the first year after the change in therapy. The authors concluded that switching to a drug with a different mechanism of action is associated with higher treatment persistence and lower health care costs than TNFi cycling.

What about biosimilars?

Biosimilars are copies of already licensed biologics that are very similar to the biologics, but are made by different sponsors using independently derived cell lines and separately developed manufacturing processes.⁸³ Regarding biosimilar use, EULAR²⁶ states that biosimilar bDMARDs approved by the European Medicines Agency or US Food and Drug Administration have similar efficacy and safety as the originator bDMARDs, and recommends them as preferred agents if they are indeed appreciably cheaper than originator or other bDMARDs.

What are the novel treatment targets in RA?

New therapeutics for RA continue to be developed. One of the new agents is peficitinib (ASP015K), an oral, once-daily Janus kinase (Jak) inhibitor targeting Jak-1, Jak-2, and tyrosine kinase-2, with moderate selectivity for Jak-3. In a phase 2b trial, 100-mg and 150-mg doses of peficitinib achieved a statistically significant ACR20 response (48.3% and 56.3%) compared to placebo (29.4%) at 12 weeks.⁸⁴