The Federal Trade Commission filed an amicus brief on Aug. 24 in an antitrust case alleging that Amgen illegally acquired exclusive patent rights to block biosimilar competition for Enbrel, one of the best-selling biologic drugs in the world with annual U.S. sales historically exceeding $5 billion.
The FTC’s brief supports the plaintiff’s theory that Amgen’s patent acquisition constituted an unlawful restraint of trade potentially violating the Sherman Act, signaling heightened federal attention to pharmaceutical patent practices, according to the commission.
Enbrel is widely prescribed for rheumatoid arthritis, psoriasis and ankylosing spondylitis. Despite the drug’s original patent expiration, biosimilar competition has been effectively blocked in the U.S. — a sharp contrast to European markets, where biosimilar versions of the drug have gained significant market share and driven down prices.
The FTC’s involvement through an amicus brief, rather than a direct enforcement action, indicates the commission views the case as an opportunity to establish legal precedent on pharmaceutical patent aggregation, commonly known as “patent thickets.”
Patent thickets involve the accumulation of overlapping patent rights that collectively prevent competitors from entering the market even after the original patent expires. The strategy has been identified by the FTC, academics and consumer advocates as a significant contributor to high biologic drug prices.
If Amgen’s patent strategy is found unlawful, the decision could open the Enbrel market to biosimilar competition and potentially reduce costs for millions of patients. Biosimilars typically enter the market at 15 to 35 percent discounts to reference biologic prices.
The case is being closely watched by the pharmaceutical industry, biosimilar manufacturers and health care payers as a potential turning point in how courts evaluate biologic drug patent strategies.
Amgen has publicly defended its intellectual property portfolio as legally acquired and essential to protecting its innovation investment.