Another Drug Option Approved for Systemic JIA

By Jill Tyrer | Nov. 13, 2023

The biologic drug tocilizumab (Actemra) has a new competitor since its patent recently expired in the U.S., although it is not yet available in this country.

Biogen’s tocilizumab-bavi, marketed as Tofidence, is the first biosimilar approved by the Food and Drug Administration (FDA) to treat children ages 2 and older who have systemic juvenile idiopathic arthritis (sJIA), a serious type of JIA that can affect not only joints but also organs, including the liver, lungs and heart.

To receive approval, a biosimilar must be as safe and effective as its original biologic, or “reference product.” Actemra and Tofidence, which are both tocilizumab, block an immune system mechanism called interleukin-6 (IL-6), which leads to the inflammation that drives diseases like sJIA.

Like Actemra, Tofidence is also approved to treat rheumatoid arthritis in adults and polyarticular JIA in children ages 2 and older. Unlike Actemra, however, Tofidence is not approved to treat several other diseases, including giant cell arteritis and COVID-19. Furthermore, it is available only as an infusion; Actemra comes in IV form as well as in prefilled syringes.

Having another option to treat sJIA is a positive development, but it may not be the first choice that many rheumatologists make to treat children or adult patients with arthritis, says Randy Cron, MD, PhD, a pediatric rheumatologist and director of the Division of Pediatric Rheumatology at the University of Alabama at Birmingham. Although tocilizumab is a common treatment for both polyarticular JIA and sJIA, biologics with different mechanisms of action are usually tried first. Tumor necrosis factor (TNF) inhibitors, like etanercept (Enbrel) are typically the first type of biologic used to treat polyarticular JIA, and interleukin-1 (IL-1) blockers, like anakinra (Kineret) are the first biologic choice for sJIA, he explains.

“So far, most biosimilars (particularly TNF inhibitors) have performed as well as the original biologics,” Dr. Cron says. “The general risks should be very similar to the parent biologic.”

However, in the United States, there is not yet a clear benefit to choosing a biosimilar over the reference biologic. “Biosimilars are dictated by insurance companies [and] pharmacy benefit managers (PBMs),” he adds. “Unlike in Europe, where biosimilars can substantially cut health care costs, in the U.S. it is complicated by all the deals made by PBMs with pharmaceutical companies, third-party payers, etc. It may not substantially reduce costs.”

As more biosimilars come on the market in the U.S., more insurance companies and PBMs may start choosing them as their preferred drug over the original biologic, forcing people to switch to the biosimilar. That is a bigger concern, Dr. Cron says.

“We do hope that patients that are already on a particular biologic are grandfathered in, so they are not mandated by insurance or PBMs to switch to a biosimilar when they are already doing well on a particular biologic,” he says.