Generic Drugs, Biologics, & Biosimilars

Generic Drugs, Biologics, & Biosimilars

Inherent Issues With Marketability

There are three primary types of drugs which are known as generic drugs, biologics, and biosimilars. Each of these drugs differs according to their manufacturing and development processes. These different types of drugs also have inherent issues with their marketability.

Generic Drugs

Generic drugs are characterized by being smaller than biologics and biosimilars. Generics are typically 200 to 1000 times smaller than biologics and biosimilars. Generics are also manufactured through chemical processes which makes them easy to manufacture. Because a generic drug is made essentially the same as another drug it typically cannot be manufactured until the patent on the original drug expires. For instance, Glucophage is the brand name of diabetes medication and the generic form is metformin (Doheny, 2016). The drugs are identical and pose the same risk, benefits, and dosage requirements. In order for a generic drug to go to market, they must typically undergo small clinical trials since they are the same as the original drug.


Biologic drugs are larger than generic drugs and are manufactured through a biological process. There drugs are produced in living cells not through chemical synthesis. Biologics are designed to specifically target the immune system. For example, Cimzia is a biologic drug that blocks a protein that causes inflammation and is used to treat tumors and psoriasis (National Psoriasis Foundation, 2016). These drugs are complex in their manufacturing and must be handled differently with storage as they are sensitive to environmental conditions. These drugs are produced in a manner that is unique to their cellular environment and as a result they must be extensively tested through large clinical trials.


Similar to generic drugs, biosimilars are drugs made to be identical to biologics by using the same cellular manufacturing process. The idea is to create a drug that works the same as the original biologic or to increase the effectiveness. For example, Zarxio is the biosimilar drug to Neupogen which are both cancer treatment drugs (Doheny, 2016). Because of the complexity to create these drugs such as the use of cells and other processes, biosimilars can vary in their effectiveness and risks. While some may work more effectively than the biologic some may work less effectively. As such, these drugs must be extensively tested in large clinical trials and are often just as costly to produce as the original biologic. They must also follow patent laws which is complicated because the drugs produced may have inherent differences in molecular size, complexity which makes them somewhat unique. The FDA produces guidance for differentiation of these drugs but in general they cannot be produced and sold until the patent runs out on the original biologic (FDA, 2016).


While each type of drug is differentiated through its manufacturing process, they each have issues with being patented and approved. The generics are the least expensive to approve but they are also less marketable due to the large numbers of substitutes. While the biologics and biosimilars are the most marketable they are also the most expensive to produce. Often the focus of their manufacturing is to reduce cost which can also decrease effectiveness.


Doheny, K. (2016). Biosimilar Drug Facts. Retrieved from WEBMD:

FDA. (2016). Follow-On Protein Products: Regulatory and Scientific Issues Related to Developing . Retrieved from Food and Drug Administration:

National Psoriasis Foundation. (2016). Moderate to Severe Psoriasis and Psoriatic Arthritis: Biologic Drugs. Retrieved from National Psoriasis Foundation:

Photo by Mika Baumeister on Unsplash


Vincent Triola. Sat, Mar 13, 2021. Generic Drugs, Biologics, & Biosimilars Retrieved from

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