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Prisoners --- Convicts --- Correctional institutions --- Imprisoned persons --- Incarcerated persons --- Prison inmates --- Inmates of institutions --- Persons --- Inmates

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Industrial economics

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Since the 1984 passage of the Waxman-Hatch Act, generic prescription drugs have become central to disease treatment and generic drug entry and price competition has been vigorous in the U.S. Nonetheless, recent policy concern has focused on potential supply inadequacy and price increases among selected generic drugs. Details regarding the supply of generic drugs throughout the product life cycle are surprisingly unstudied. Here, we examine manufacturer entry, exit, the extent of competition and the relationship between supply structure and inflation adjusted prices among generic drugs. Our empirical approach is descriptive and reduced form, following recent innovations on the older structure-conduct-performance tradition. We employ quarterly national data on quantities, wholesale dollar sales and manufacturers from QuintilesIMS National Sales Perspective data, 2004Q4-2016Q3. Defining a market as the molecule-dosage-form, we observe that median sizes of drug markets are predominantly small, with annual inflation adjusted sales revenues of less than $10 million but increasing over time. The median number of manufacturers in each market is about two, the mean about four. We find evidence to suggest decreasing numbers of suppliers over our study period, particularly following implementation of the Affordable Care Act in 2010 and the Generic Drug User Fee Amendments of 2012, attributable both to more exit and less entry. Approximately 40 percent of markets are supplied by one manufacturer; the share of markets supplied by one or two manufacturers is observed to increase over time and is more likely among non-oral drugs and those belonging to selected therapeutic classes. We find evidence to suggest prices of generic drugs are statistically significantly increasing over time, particularly following the implementation of the 2010 Affordable Care Act and the 2012 Generic Drug User Fee Amendments. Price increases are positively correlated with reduced manufacturer counts and alternative measures of increased supplier concentration, holding all else constant. Our results suggest the market for generic drugs is largely comprised of small revenue products the supply of which has tended towards duopoly or monopoly in recent years. Therefore, it is surprising generic drug prices have not been observed to be higher and potentially risen more over our study period. This issue merits further study; we suggest several testable hypotheses based in economic theory.

Zonder onderwerpscode: economie

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Regulation can influence the structure, conduct and performance of consumer product markets and the structure of product markets can influence regulation. Since the vast majority of prescription drugs consumed by Americans are generic, the structure of the U.S. generic prescription drug market is of wide interest. The supply of prescription drugs in the U.S. is also heavily regulated by the U.S. Food and Drug Administration (FDA). We describe events leading up to the passage and implementation of the Generic Drug User Fee Amendments in 2012 (GDUFA I), and compare its FDA commitments, provisions, goals and fee structure to that of the 1992 Prescription Drug User Fee Act (PDUFA) for branded drugs. Although GDUFA I expires September 30, 2017, reauthorization for GDUFA II is currently underway and is likely to shift the user fee structure away from annual facility fees to annual program fees. We explain how the fee structure of GDUFA I, and that being considered for GDUFA II, erects barriers to entry and creates scale and scope economies for incumbent manufacturers of generic drugs. Furthermore, in order to implement fees under GDUFA I, FDA required the submission of self-reported data on generic manufacturing practices including domestic and foreign active pharmaceutical ingredient (API) and finished dosage form (FDF) facilities. These data provide an unprecedented window into the recent evolution of generic drug manufacturing markets. Our analyses of these data suggest that generic drug manufacturing in 2017 is quite concentrated: a very large portion of ANDA holders have small portfolios consisting of less than five ANDAs, while a small number of very large ANDA holders have portfolios consisting of hundreds or even thousands of ANDAs. The number of API and FDF facilities have each declined by approximately 10-11% between 2013 and 2017. Furthermore, in 2017, generic manufacturing is largely foreign and has become increasingly so since 2013. We discuss the implications of the current structure of the U.S. generic prescription drug market for GDUFA II ratification and implementation.