The Biologics Price Competition and Innovation (BPCI) Act, a law passed in the US in 2009, was created to add incentives to and strengthen the biologics market by forming an abbreviated approval pathway for biosimilars, thereby lowering drug prices and allowing for improved therapeutic access to patients. The loss of exclusivity of AbbVie’s Humira (adalimumab) has become a perfect scenario to test if the act can achieve the law’s intention.
Humira has long been a very profitable asset for AbbVie, with steadily rising annual US sales since its launch in 2002, peaking at $18.6 billion in 2022 (globally $21.2 billion). But with Humira’s loss of exclusivity and the January 2023 launch of Amgen’s Amjevita, the first US adalimumab biosimilar, the impact was immediately apparent, with AbbVie reporting a Q1 2023 decline of 26.1% in revenue compared to the same period of the preceding year.
The potential revenue involved in replacing Humira has resulted in many adalimumab-biosimilar offerings being brought forward, with the current total at nine FDA-approved agents, and a market that is rapidly becoming overcrowded. Since Amjevita, seven other agents have been introduced to the US market, with the release of Pfizer’s Abrilada delayed until November 2023.
Boehringer Ingelheim’s (BI’s) Cyltezo is noteworthy, as during the process of qualifying Cyltezo, BI took the uncommon step of showing its interchangeability with Humira. The designation requires that additional statutory safety standards should be satisfied. It is supported by data showing that the risk in terms of safety or diminished efficacy of alternating or switching between biosimilar and innovator is not greater than the risk of using the innovator without change.
At the time of publication, there are only four biosimilars that have received interchangeability status. However, more are expected, including Mylan’s Hulio, which is currently undergoing interchangeability studies. BI attained interchangeability status with the intention of its being a point of distinction for Cyltezo from the many other biosimilars in this class. However, this distinction is not expected to have any significance on the prescribing habits of healthcare providers.
Interviews with key opinion leaders (KOLs) in the US indicated a lack of concern in transferring patients from Humira to biosimilars in general. Additionally, providers noted that they typically prescribe adalimumab with its generic name to avoid needless confrontation or disruptions of therapy. This indirectly removes the merit of interchangeability and returns the choice of agent to the payer and pharmacy benefit managers (PBM).
This shift from patient to payer also alters the influence of lower-priced biosimilars on the market. This emphasises the significance of the bipartisan PBM Oversight Act that is moving through US Congress and its effect on the landscape. Whether or not Cyltezo and the other adalimumab biosimilars succeed in the coming years may determine the path for the next anticipated biosimilar offerings.