Generic pharmaceutics

A generic drug is a pharmaceutical drug that is equivalent to a brand-name product in dosage, strength, route of administration, quality, performance, and intended use, but does not carry the brand name. The generic drug has the same active pharmaceutical ingredient (API) as the original, but may differ in characteristics such as manufacturing process, formulation, excipients, color, taste, and packaging.

Although they may not be associated with a particular company, generic drugs are usually subject to government regulations in the countries where they are dispensed. They are labeled with the name of the manufacturer and a generic nonproprietary name such as the United States Adopted Name or international nonproprietary name of the drug. A generic drug must contain the same active ingredients as the original brand-name formulation. The U.S. Food and Drug Administration (FDA) requires that generics be identical to, or within an acceptable bioequivalent range of, their brand-name counterparts with respect to pharmacokinetic and pharmacodynamic properties. (The FDA's use of the word "identical" is a legal interpretation, not literal.)

Biopharmaceuticals such as monoclonal antibodies differ biologically from small molecule drugs. Biosimilars have active pharmaceutical ingredients almost identical to the original product and are typically regulated under an extended set of rules. But biosimilars are not the same as generic drugs as the active ingredients are not the same as those of their reference products.

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