Enbrel Stays Above the Biosimilar Fray, but Humira Biosimilars May Nip at its Heels

Although a 2021 U.S. District Court decision quashed hopes that a biosimilar of Enbrel (etanercept), a rheumatoid arthritis drug, would reach the U.S. market before 2029, biosimilar competition for Humira (adalimumab) may bring down Enbrel’s price in the meantime, experts told Managed Healthcare Executive®.

The prices for Humira and Enbrel have “shadowed” each other very closely over almost 20 years, and next year Humira will face biosimilar competition for the first time. As many as 11 biosimilars to Humira could come on the market in 2023. If they pull down the price of Humira as biosimilars are intended to, then Amgen, which makes and markets Enbrel, could be forced to lower the price of its drug to compete. The current list price for an annual supply of Enbrel is about $83,000.

Alice M. Ellyson

Health economist Alice M. Ellyson, Ph.D., an acting assistant professor of pediatrics at Seattle Children’s Hospital, has studied the pricing of Humira and Enbrel. “It’s hard to be certain,” says Ellyson about an Enbrel price drop, “but the structure of insurance and the way in which companies negotiate drug prices does kind of incentivize this.”

Amgen CEO Robert A. Bradway testified that to offer the same size rebates that competitors such as AbbVie are offering for Humira, his company has to charge the same list prices. For example, in 2018, AbbVie increased the price of Humira by 9.7% and Amgen followed shortly afterward with a price hike of exactly 9.7% for Enbrel, according to a 2020 investigation conducted by congressional Democrats.

U.S. physicians need to be “in the driver’s seat” and switch their patients from Enbrel to lower-cost alternatives, such as Humira biosimilars, say rheumatologists Mike Schweitz, M.D., president of the Alliance for Transparent and Affordable Prescriptions (ATAP) Action Network, and Brett Smith, D.O., a member of the ATAP representing the Tennessee Rheumatology Society. Schweitz and Smith say, though, PBMs may dictate that higher list-price medicines be used with their formulary decisions.

Moreover, they note that Enbrel and Humira are not perfectly interchangeable. “It takes more than one drug to find the one that works,” says Schweitz. “When you find that one, the last thing you want to do is switch.”

Still, as more physicians become comfortable with prescribing biosimilars for rheumatoid arthritis, the competition will inevitably put downward pressure on the price of Enbrel, Smith says. There is some irony in the current situation, he notes. Amgen has fought off biosimilar competition for Enbrel, but in 2023 will be the first company to launch a biosimilar of Humira, a product with the brand name Amjevita. “They’re producing a biosimilar for their competitor’s product and they’re running the price up on their primary therapy, which has been out for 24 years now, so it just puts a bad taste in everybody’s mouth,” Smith said. Amgen will have had 31 years of marketing exclusivity by the time biosimilars of Enbrel come on the market in 2029.

The Humira biosimilars may put some downward pressure on the cost of Enbrel, but price increases for both Humira and Enbrel before next year are a possibility, Ellyson notes. A 2021 study she co-authored with Anirban Basu, Ph.D., M.S., a professor of health economics at the University of Washington School of Pharmacy, highlighted a tendency for originator companies to raise prices in anticipation of the arrival of biosimilars.

“Most of these companies are publicly traded and their stock value declines when their revenues decline, so there’s certainly incentive to get in that short-term revenue by increasing price, even if in the long term it’ll lower their profits,” observes Ellyson.