Understanding the Changing Landscape of Biosimilars

bottle labeled

Biosimilars have gained significant market share in the past few years, particularly those that are first to launch in their therapeutic areas. A presentation at AMCP Nexus 2023 indicated that biosimilars generally drive down the average sales prices of both the reference product and any biosimilars, presenting opportunities for savings.

The talk was delivered by Chelsee Jensen, PharmD, BCPS, PRCM, senior pharmacy specialist at Mayo Clinic; Kimberly Maxfield, PhD, a pharmacologist at the FDA; and Juwaria Waheed, MD, a scientific reviewer in the FDA’s Office of Therapeutic Biologics and Biosimilars.

Barriers to biosimilar use include different codes, payer preferences, ability to keep options in stock, ability to differentiate among similar products, and patient hesitancy to accept a biosimilar. Another challenge is limited evidence regarding switching among biosimilars, which needs further study. However the benefits are significant. Mayo Clinic implemented a program to prepare the electronic medical record for use of biosimilars in five therapeutic areas. The effort saved $23.1 million in the first year and another $10.8 million in the second year.

The speakers reviewed the current landscape of biosimilars approved for use in supportive care, oncology, autoimmune disorders, and ophthalmology. They also discussed the two pathways a biological product can take to seek FDA approval. A 351(a) “stand-alone” Biologics License Application (BLA) requires information showing that the proposed biological product is safe, pure, and potent for each indication. Alternatively, a shortened BLA pathway, a 351(k), aims to show that a product is either biologically similar to or interchangeable with an already-approved reference product. Generally, a 351(k) product must prove biosimilarity; have the same mechanism of action (if known); and use the same route of administration, dosage form, and strength. It should have no clinically meaningful differences from the reference product. The FDA is currently aiming to streamline the process of biosimilar development and approval, the presenters added.

The session also indicated specific biosimilars in the pipeline to watch: etanercept, pegfilgrastim on-body injector, eculizumab, natalizumab, insulin asparti, tocilizumab, aflibercept, ustekinumab, omalizumab, golimumab, denosumab, and certolizumab.

Important to the future of biosimilars is the concept of an interchangeable biosimilar, considered by the FDA to be equivalent to its brand-name reference product. This type of product may be substituted at the pharmacy for the reference product without the intervention by the prescribing health care provider (subject to state laws). There are currently four products approved as such, with more expected in the future. Interchangeable biosimilars reduce burden on the system and reduces cost, the presenters said.


Jensen C, Maxfield K, Waheed J, Lockhart C. Biosimilar Operational Readiness: Marketplace Trends and Regulatory Considerations. Session R2. Presented at AMCP Nexus 2023; Oct. 16‒19, 2023; Orlando, Fla.