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Authorized generics are identical in formulation to brand drugs, manufactured by the brand company but marketed as a generic. Generics, marketed by generic manufacturers, are required to demonstrate pharmaceutical and bioequivalence to the brand drug, but repetition of clinical trials is not required. This retrospective cohort study compared outcomes for generics and authorized generics, which serves as a generic vs. brand proxy that minimizes bias against generics. For the seven drugs studied between 1999-2014, 5,234 unique patients were on brand drug prior to generic entry and 4,900 (93.6%) switched to a generic. During the 12-months following the brand-to-generic switch, patients using generics vs. authorized generics were similar in terms of outpatient visits, urgent care visits, hospitalizations, and medication discontinuation. The likelihood of emergency department visits was slightly higher for authorized generics compared with generics. These data suggest that generics were clinically no worse than their proxy brand comparator.


This is the accepted version of the following article:

Hansen RA, Qian J, Berg RL, et al. Comparison of outcomes following a switch from a brand to an authorized vs. independent generic drug. Clin Pharmacol Ther. 2016. doi:10.1002/cpt.591

which has been published in final form at DOI: 10.1002/cpt.591. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.


American Society for Clinical Pharmacology and Therapeutics



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