US Rheumatologists Are Comfortable With Biosimilars, but Still Hesitant to Prescribe

Rheumatoid arthritis (RA) is one of the most rapidly growing and evolving therapeutic areas, with the global market for RA drugs forecasted to reach over $36 billion by 2027. The United States is expected to have the most rapid growth of any country due to increased awareness and prevalence of RA among an aging population. As the country nears its 4-year anniversary of having an infliximab biosimilar on the market (Inflectra, November 2016), significant barriers to biosimilar adoption still persist. Inflectra and Renflexis (launched July 2017) can be viewed as the more “seasoned” biosimilars in the United States, given that most FDA biosimilar approvals and launches have occurred just within the past couple years. However, time on the market does not strongly correlate with adoption: Biosimilars still have less than 10% of the overall market for infliximab molecules.

To take a deeper dive into one of the fastest growing categories of specialty medicines, Cardinal Health Specialty Solutions has produced a Rheumatology Insights report that includes results from a survey of over 100 US-based rheumatologists on their perceptions and experiences with biosimilars in rheumatology thus far.

An overwhelming number of rheumatologists surveyed (98%) were familiar with biosimilars, and (90%) felt comfortable prescribing them to their patients. However, the majority (66%) were unlikely to switch their patients from the reference products to biosimilars until there was greater adoption of biosimilars among payers.

Interchangeability and extrapolation continue to create hesitation among providers; and when asked about top concerns with prescribing biosimilars, efficacy was the leading response. These findings are aligned with both domestic and international investigations conducted over the past year that showed rheumatologists understand biosimilars but lack confidence to use them.

In addition to the payer landscape, which has been a frequently cited barrier to US biosimilar adoption, there is a continued lack of clinical confidence among rheumatologists, recent findings show. This highlights the significant need for additional real-world evidence (RWE) on biosimilar utilization. As more providers and patients gain experience with switching to biosimilars, stakeholder support for the abbreviated 351(k) FDA approval pathway, which provides certification for safety and efficacy equivalence to the reference product, will be further strengthened. Additionally, peer-to-peer knowledge sharing will continue to be critical in building confidence in biosimilars, including the concept of extrapolation. In fact, multiple studies have found that physician adoption of new drugs is heavily influenced by the extent to which their peers have adopted those new drugs.^1,2 The more the United States can build experience with biosimilars, the more peer influence and clinical confidence will improve biosimilar uptake.

It is important to note that to develop more robust RWE with the goal of influencing clinical acceptance, a multi-stakeholder approach is necessary. As noted in the Cardinal Health study, 65% of survey respondents feel that the economics of biosimilars are not favorable enough to motivate them to switch from the reference product. Reimbursement, accessibility, support services, and other considerations all must align to enable provider adoption of biosimilars. With additional RA therapeutic biosimilars already FDA approved and “on deck” to come to market over the next few years (most notably in 2023 with the adalimumab biosimilars), provider confidence in both the clinical evidence and the payer and reimbursement landscape will be critical to the future success of biosimilars in the United States.

References:

1. Kalkan A, Roback K, Hallert E, Carlsson P. Factors influencing rheumatologists’ prescription of biological treatment in rheumatoid arthritis: an interview study. Implement Sci. 2014;9:153. doi:10.1186/s13012-014-0153-5

2. Donohue JM, Guclu H, Gellad WF, et al. Influence of peer networks on physician adoption of new drugs. PLos One 2018;13(10):e0204826. doi:10.1371/journal.pone.0204826