FDA Proposed Guidance for Biosimilar Updates

Over the last 10 years, biologics have transformed the treatment of many illnesses like chronic bowel disease, kidney disease, arthritis and cancer and they are the fastest growing class of medications in the United States. The FDA has gained valuable scientific information in reviewing both biosimilar and interchangeable biosimilar medications. They both meet the same high FDA standards and are as safe and effective as the reference product. When the FDA designates a biosimilar product as “interchangeable,” a pharmacist may substitute that product for a biologic without contacting the physician (predicated on state law). This pharmacy-level substitution provides increased access to treatments and cost savings for patients.

However, many pharmacies struggle to understand which biosimilar products can be substituted for the reference product. Consider the following definitions from the FDA:

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  • A biosimilar is a biologic that is highly similar to and has no clinically meaningful difference from an existing FDA-approved biological medication, called a reference product.
  • A reference product is approved in a standalone application that must contain all data and information necessary to demonstrate the product’s safety and effectiveness.

Newly proposed FDA guidance may alleviate this confusion of biosimilar interchangeability.

On June 20, 2024, the FDA issued a draft guidance for industry Considerations for Demonstrating Interchangeability With a Reference Product: Update. The recommendations in the draft guidance would provide clarity and transparency regarding the FDA’s review and approval process for biosimilars. 

The draft guidance eliminates the requirement that biosimilars produce clinical data to show they are interchangeable with their reference product. These clinical trials (switching studies) add time and expense to the development of a biosimilar and delay them from reaching patients.

This update would allow manufacturers who are interested in obtaining a Biologic License Application (BLA) for a biosimilar with a review for interchangeability status to either:

  1. Submit clinical trial data or
  2. Provide a statement indicating why the data in the BLA already demonstrates switching safety
    1. Any other information relevant to support the risk, in terms of safety and diminished efficacy, from alternating or switching between the reference product and proposed biosimilar is not greater than the risk of using the reference product without a clinical trial

Companies with pending BLAs can also submit an amendment to their application including the above information.

While biologic substitution is regulated at the state level, the FDA could broadly increase the number of biologics categorized as interchangeable biosimilars with this draft guidance, making pharmacist driven substitutions more commonplace. PAAS will keep you informed as we await Final Guidance from the FDA.

Jennifer Ottman, CPhT