Generic drug
[1][2] A generic drug has the same active pharmaceutical ingredient (API) as the original, but it may differ in some characteristics such as the manufacturing process, formulation, excipients, color, taste, and packaging.
The U.S. Food and Drug Administration (FDA) requires generics to be identical to or within an acceptable bioequivalent range of their brand-name counterparts, with respect to pharmacokinetic and pharmacodynamic properties.
However, many countries and regions, such as the European Union and the United States,[5] 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.
[14] The average cost to a brand-name company of discovering, testing, and obtaining regulatory approval for a new drug, with a new chemical entity, was estimated to be as much as US$800 million in 2003[15] and US$2.6 billion in 2014.
Indeed, the greater degree of 'brand-brand' competitive dynamics seen in the biologics and complex generics space allows manufacturers of originators to better protect market share following loss of patent exclusivity.
The price paid by pharmacists and doctors is determined mainly by the number of license holders, the sales value of the original brand, and the ease of manufacture.
[30] Most developed nations require generic drug manufacturers to prove that their formulations are bioequivalent to their brand-name counterparts.
[citation needed] Most small molecule drugs are accepted as bioequivalent if their pharmacokinetic parameters of area under the curve (AUC) and maximum concentration (Cmax) are within a 90% confidence interval of 80–125%; most approved generics in the US are well within this limit.
[38] For more complex products—such as inhalers, patch delivery systems, liposomal preparations, or biosimilar drugs—demonstrating pharmacodynamic or clinical equivalence is more challenging.
[41] For an ANDA to be approved, the FDA requires that the 90% confidence interval of the geometric mean test/reference ratios for the total drug exposure (represented by the area under the curve or AUC) and the maximum plasma concentration (Cmax) should fall within limits of 80–125%.
[42] (This range is part of a statistical calculation, and does not mean that generic drugs are allowed to differ from their brand-name counterparts by up to 25 percent.)
The FDA evaluated 2,070 studies conducted between 1996 and 2007 that compared the absorption of brand-name and generic drugs into a person's body.
[43][44] Non-innovator versions of biologic drugs, or biosimilars, require clinical trials for immunogenicity in addition to tests establishing bioequivalency.
Some of these settlement agreements have been struck down by courts when they took the form of reverse payment patent settlement agreements, in which the generic company basically accepts a payment to drop the litigation, delaying the introduction of the generic product and frustrating the purpose of the Hatch–Waxman Act.
[53][54] Innovator companies sometimes try to maintain some of the revenue from their drug after patents expire by allowing another company to sell an authorized generic; a 2011 FTC report found that consumers benefitted from lower costs when an authorized generic was introduced during the 180 day exclusivity period, as it created competition.
For example, warfarin (Coumadin) has a narrow therapeutic window and requires frequent blood tests to make sure patients do not have a subtherapeutic or a toxic level.
[29][63][64][65] In 2007, North Carolina Public Radio's The People's Pharmacy began reporting on consumers' complaints that generic versions of bupropion (Wellbutrin) were yielding unexpected effects.
[69] Two women, each claiming to have suffered severe medical complications from a generic version of metoclopramide, lost their Supreme Court appeal on June 23, 2011.
[76] The code of ethics issued by the Medical Council of India in 2002 calls for physicians to prescribe drugs by their generic names only.
[80] China remains the largest exporter of active pharmaceutical ingredients, accounting for 40% of the world market per a 2017 estimate.
[83] As of 2021, several major companies traditionally dominate the generic drugs market, including Viatris (merger of Mylan and Upjohn), Teva, Novartis' Sandoz, and Sun Pharma.
