Generic drugs therapeutic equivalence

P. A. Meredith, Generic drugs therapeutic equivalence, Drug Safety, 15, 233 (1996). 

Generic and therapeutic equivalency policies and procedures Investigational drug policies ... 

When is a generic drug equivalent to a proprietary one Can a drug be substituted for another if it falls within the same therapeutic, pharmacological or structural class This are legitimate questions which must be answered frequently by doctors, pharmacists and other health professionals. According to the Merck Manual (15th Edition) there are three... 

That documentation of pharmaceutical- and bio-equivalence should be provided to regulatory authorities is not at issue. However, the means by which these data can and should be demonstrated remain the subject of discussion. Political, economic and scientific hurdles pervade, and this issue remains unresolved. The imposition of existing small-molecule equivalence criteria on the registration of generic biologic drug products is unlikely to provide an acceptable degree of consumer protection. Likewise, the conventional bioequivalence trial used to infer therapeutic equivalence of different formulations based on the similarity of the phar-... 

Generic products tested by the FDA and determined to be therapeutic equivalents are listed by the FDA in their publication Approved Drug Products with Therapeutic Equivalence Evaluations. These products contain the same active ingredients as their brand-name counterparts and also meet bioequivalence standards. The FDA recommends substitution only among products listed as therapeutically equivalent. 

U.S. Department of Health and Human Services, Food and Drug Administration, Center for Drug Evaluation and Research, Office of Pharmaceutical Science, Office of Generic Drugs, Electronic orange book Approved drug products with therapeutic equivalence evaluations, available http //www.fda.gov/cder/ob/default.htm, accessed Apr. 21, 2005. 

Drug products can be considered to be pharmaceutical equivalents if such products (1) contain the same active ingredients, (2) are of the same dosage form and route of administration, and (3) are identical in strength and concentration. The term therapeutic equivalence is also used to describe pharmaceutical equivalence. Pharmaceutically equivalent drag products may differ in attributes such as shape, color, excipients, and release mechanisms. Pharmaceutical equivalence is of importance in the development of generic drags. See http //www.fda.gov. 

The Waxman-Hatch Act of 1984 was motivated, to a significant degree, by cost considerations, but quality issues concerning bioequivalency and therapeutic equivalency were addressed as well. All FDA-approved drugs (pioneer brand-name and generic versions) are required to meet the same FDA standards of quality. 

Of the more than 10,000 drugs in the Orange Book, approximately 80% are generic versions. Of the approximately 8,000 multisource generic drugs, more than 90% are considered therapeutically equivalent to the innovator s product. 

Neoral and Sandimmune, there are three generic forms of cyclosporine approved for use by the U.S. Food and Drug Administration (FDA). Although considered therapeutically equivalent to Neoral, the excipients differ from that of Neoral or Sandimmune. The chemical structure of these is equivalent to that of cyclosporine however, close therapeutic drug monitoring is recommended when switching from one formulation to another in view of the very limited availability of peer-reviewed, published data on the generics. ... 

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