US prescribers’ attitudes and perceptions about biosimilars

Introduction: In the United States (US), a legal framework for approving biosimilars was established via the Biologics Price Competition and Innovation Act of 2009 (BPCI Act). At the time of writing (September 2022), 38 biosimilars have been approved in the US. Some biosimilars in the US can be designated as ‘interchangeable,’ which means they can be automatically substituted at the pharmacy level. In 2021, the Alliance for Safe Biologic Medicines (ASBM) surveyed prescribing physicians in the US for their views on the prescribing, substitution and interchangeability of biosimilars. Methodology: In September 2021, the ASBM, conducted a web-based quantitative survey with 401 participants practicing medicine in the US. Prescribers were asked for their views on substitution of, as well as their familiarity with, knowledge of, attitudes to, and beliefs in, biosimilars. Results: Most physicians are comfortable prescribing biosimilars and comfortable switching stable patients to biosimilar product. Over half of physicians are more likely to prescribe biosimilars with interchangeable status and a similar percentage are more comfortable with pharmacy-level substitution of these products. However, the majority want to keep the authority to prevent pharmacy-led substitution if they specify so. Regarding switching patients to a biosimilar for non-medical reasons, the majority were comfortable doing this themselves but fewer than half were comfortable with a third party initiating the switch. In addition, most physicians favoured a scenario where multiple products, including innovator and biosimilars are reimbursed, and biosimilars may be encouraged for new patients with no automatic substitution permitted. Conclusion: The survey reveals that overall, American physicians are confident prescribing biosimilars. It also sheds light on how they feel about the interchangeable designation, and biological drugs switching choices made by them, pharmacists and payers.