Suffix vs No Suffix: Naming Biologics and Biosimilars

Monday October 21, 2019

Biologics and biosimilars are both FDA-approved medicines that help patients treat or manage debilitating diseases. All biologic drugs, including biosimilars, are given an international non-proprietary name (INN). In addition to an INN, biosimilars are given a random, four-letter suffix.

Differences in naming may result in pharmacovigilance challenges and imply that biosimilars and interchangeable biosimilars do not have the same safety and efficacy as an originator biologic. This, in turn, can inhibit patient access to life-saving treatments.

Understanding how biologic drugs are named can alleviate stakeholder confusion and lead to greater biosimilars adoption.

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About the Biosimilars Council

The Biosimilars Council, a division of the Association for Accessible Medicines (AAM), works to ensure a positive environment for patient access to biosimilar medicines. The Biosimilars Council is a leading source for information about the safety and efficacy of more affordable alternatives to costly brand biologic medicines. Areas of focus include public and health expert education, strategic partnerships, government affairs, legal affairs and regulatory policy. More information is available on our about page.

About AAM

AAM is driven by the belief that access to safe, quality, effective medicine has a tremendous impact on a person’s life and the world around them. Generic and biosimilar medicines improve people’s lives, improving society and the economy in turn. AAM represents the manufacturers and distributors of finished generic pharmaceuticals and biosimilars, manufacturers and distributors of bulk pharmaceutical chemicals, and suppliers of other goods and services to the generic industry. Generic pharmaceuticals are 90 percent of prescriptions dispensed in the U.S. but only 22 percent of total drug spending. Additional information is available at

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October 21–23, 2024 | Rockville, MD

GRx+Biosims™ 2024 is the leading regulatory science and policy event for the U.S. generics and biosimilars industry. Access the most recent information straight from experts at the Food and Drug Administration, grasp the latest policies shaping the industry, and acquire valuable insights to propel your professional development.