Generic medication

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. The term may also refer to any drug marketed under its chemical name without advertising, or to the chemical makeup of a drug rather than the brand name under which the drug is sold.

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. Generic versions of these drugs, known as biosimilars, are typically regulated under an extended set of rules.

In most cases, generic products become available after the patent protections afforded to a drug's original developer expire. Once generic drugs enter the market, competition often leads to substantially lower prices for both the original brand-name product and its generic equivalents. In most countries, patents give 20 years of protection. However, many countries and regions, such as the European Union and the United States, may grant up to five years of additional protection ("patent term restoration") if manufacturers meet specific goals, such as conducting clinical trials for pediatric patients. Manufacturers, wholesalers, insurers, and drugstores can each increase prices at various stages of production and distribution.

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