Biologics or Biological Agents

Vials of the MMR vaccine.
Vials of the MMR vaccine. Justin Sullivan/Getty Images

Definition: Biologics and Biological Agents

Biologics, also known as biological drugs or biologic agents, are tests, preventives and therapies that were developed and are manufactured through biological processes using human, animal or microorganism sources. This is in contrast to pharmaceutical drugs, which are manufactured from chemical processes.

There are any number of substances derived from humans, animals or microorganisms that are used in biological products, such as sugars, proteins, nucleic acids, cells, blood or tissues.

Using biotechnology, they are combined or processed to create substances that can help us diagnose, treat, manage, or cure illnesses and conditions.

Among the earliest biological agents was insulin, which in its earliest form was derived from animals. Today's insulin products are more likely to be a result of recombinant DNA, a different approach, but still biologic in nature.

Vaccines are biologics that have been available for centuries. They are developed using a component of the virus or bacteria that causes the disease that is being prevented. This can be a killed or mild strain of the germ, or it may be a purified protein, sugar or other component of the germ. By exposing someone to this preparation made from the virus or bacteria in question before they get sick, the body reacts by building up antibodies against that disease. Later, if exposed, the patient will not develop the disease.

The process is all biological.

Other familiar tests and therapies are biological, too. Blood products used for transfusion, many allergy tests and shots, hormonal therapies such as those used to treat symptoms of menopause, and stem cell therapies used for transplantation or development of other biologic agents are all considered biologics.​

List of Biologics

Compiled from a number of resources, here is a master list of biologics:

  • vaccines
  • insulins
  • interleukins
  • human growth hormones
  • hormone therapies, such as the use of estrogen or testosterone
  • tests to screen potential blood donors for HIV or other infectious agents
  • blood and blood products for transfusion
  • blood and blood products used in manufacturing with other products
  • biologic extracts used to develop both allergy tests and allergy shots
  • human cells and tissues used for transplantation (for example, tendons, ligaments, and bone)
  • gene (DNA) therapies (see below*)
  • cell therapies (see below*)

Each of these is sold under a brand name that may be more recognizable, like Avastin, Herceptin, Enbrel, Epotin, Remicade, Humira or Avonex.

Are there Generic Versions of Biologics?

Unlike older chemical compound drugs, most biologics do not have what is strictly defined as generic equivalents. The FDA defines generics as having exactly the same active ingredient as a brand-name drug. Not only that, but they are also bioequivalent - they have the same dosage form, strength, quality, and performance.

Instead, biologics have biosimilars, which were defined by law in 2009.

Biosimilars - Interchangeables - Follow-On Biologics

Biosimilars are drugs approved by the FDA that have no clinically meaningful differences from the original brand name biologic agent. They should be as safe and as effective and work in the same way as the reference product. A drug is called an interchangeable if it meets the biosimilarity standard and should be able to be switched with the original product with no increase in risk.

The prescription of biosimilar drugs was restricted in the United States until the passage of the Affordable Care Act of 2010. With the passage of the Biologicals Price Competition and Innovation Act (BCPI) of 2009 and the Patient Protection and Affordable Care Act of 2010, biological products have a streamlined licensure pathway through the FDA. More and more biosimilar and interchangeable drugs will be available in the United States with this change in the law.

Prior to 2009, many groups lobbied to encourage the FDA to begin allowing the manufacture of biosimilars or follow-on versions of older biologics as a way to save the healthcare system money. For example, branded insulin and insulin-type products may cost from $150 to $1000 per month. A follow-on equivalent might cost only $25 per month. When multiplied by the number of people who require these kinds of treatments, you can see how approval of these follow-on biologics could save the system billions.

Large biologic manufacturers lobbied against the development and production of biosimilars because they didn't want to have to compete with less expensive, but effective treatments (follow the money). They cited safety problems in the development process and lack of proof that these drugs would be as effective as the originals.


Information for Consumers (Biosimilars) - U.S. Food and Drug Administration 8/27/2015.

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