FDA Publishes Biosimilars Action Plan (BAP)

August 23, 2018


Biologic drug products are used to treat a variety of serious diseases, including cancer, blindness, rheumatoid arthritis, multiple sclerosis, and diabetes. Biologics, which include antibodies and large proteins, tend to be more complex than traditional small molecule drugs. Biologics are typically manufactured in living cells, and the manufacturing processes can be exquisitely sensitive to small environment changes, for example, in temperature or nutrient content.

In 2015, biologics accounted for 38 percent of U.S. prescription drug spending, and they also accounted for 70 percent of the growth in drug spending from 2010 to 2015.1 In 2017, eight of the top selling drugs were biologics. 

In 2010, Congress passed the Biologics Price Competition and Innovation Act (BPCIA), which established an abbreviated pathway2 to market for biosimilars. Biosimilars are often referred to as generic versions of innovator biologics.3 To date, the U.S. Food and Drug Administration (FDA) has licensed 11 biosimilars. As part of a broader emphasis on encouraging biologics market competition, the FDA recently published its Biosimilars Action Plan (the BAP).4  

Biosimilar Action Plan

The FDA’s BAP contains four key elements:

  • improving the efficiency of biosimilar product development and licensing;
  • maximizing scientific and regulatory clarity for biosimilar product development;
  • improving the understanding of biosimilars among patients, clinicians, and payors; and
  • reducing the “gaming” of FDA requirements (as has been seen in traditional generic drug development and regulatory practice) or other attempts to delay unfair competition.

While a comprehensive review of the BAP is beyond the scope of this alert, some key points include:

  • enhancing the Purple Book to include more information about approved biologics, including information relating to reference product exclusivity;5
  • actively exploring the potential for entering into new data sharing agreements with foreign regulators to facilitate an increased use of non-U.S.-licensed comparator products in certain studies to support a biosimilar application;6
  • providing additional clarity and flexibility for biosimilar developers on analytical approaches to evaluate product structure and function to support a demonstration of biosimilarity; and
  • providing additional support for product developers regarding product quality and manufacturing process, including identifying physical product quality attributes that are most critical to evaluate.7


The proposed actions outlined in the BAP, in conjunction with initiatives like the Biosimilar Product Development program (BPD program),8 should facilitate a more transparent path to market for biosimilars. For questions regarding the BAP, or any biosimilar-related questions, please contact David Hoffmeister or any member of the firm’s FDA or life sciences practices.

Charles Andres contributed to the preparation of this alert.


2 The abbreviate pathway is also known as the 351(k) pathway.
3 Unlike small molecule generic drugs, biosimilars are not identical to the reference innovator biologic but are similar (biosimilar) and have no clinically meaningful differences in purity, potency, or safety.
4 “Biosimilars Action Plan: Balancing Innovation and Competition (BAP),” FDA, (2018).
5 The Purple Book consists of two spreadsheets. Compared to the Orange Book, which is a component of the small molecule generic drug approval pathway, the Purple Book is primitive and not terribly informative. This change to the Purple Book is a welcome enhancement.
6 Traditionally, the FDA has required that biosimilars be compared to the U.S. reference biologic. The entry of the biosimilar into the U.S. market place can therefore be delayed if the biosimilar applicant is unable to obtain the U.S. marketed reference biologic for comparative purposes. Allowing some use of non-U.S.-licensed biologics could therefore create a faster path to market.
7 Characterization of the biosimilar to support biosimilarity is an early, critical, and subsequently ongoing process during biosimilar development. Failure to adequately and appropriately characterize a would-be biosimilar can doom the biosimilar’s development.
8 The BPD program was created to facilitate the rapid development of biosimilars. Under the BPD program, the FDA provides detailed, product specific advice to manufacturers.