Generic drugs/products bioequivalence studies

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Bioequivalence studies are the basis for determination of the therapeutic equivalence between a pharmaceutically equivalent generic drug product and a corresponding reference hsted drug. This hst is provided in the book titled Approved Drug Products with Therapeutic Equivalence Evaluations, commonly known as the Orange Book. °... 

Bioavailahility studies are used to compare different formulations of the drug product, or different batches of the same formulation and, as discussed in Chapter 8, generic copies of a reference drug. Their comparative value is based on the premise that, if similar amounts of identical active substance are delivered to the site of action at similar rates, then a similar biological response can be expected, which leads to the conclusion that the two preparations are bioequivalent. 

Bioequivalence Scientific basis on which generic and brand-name drugs are compared. To be considered bioequivalent, the bioavailability of two products must not differ significantly when the two products are given in studies at the same dosage under similar conditions. Some drugs, however, are intended to have a different absorption rate. The FDA may consider a product bioequivalent to a... 

Bioequivalence Data for Generic Products. The standards for bioequivalence studies for generic products are detailed in the guidelines (Notification No. 487 of the PAB in December 1997). The bioequivalence study of the drugs, which are oral forms, sustained release forms and nonoral forms to be applied for application after 1 January 1998 are covered. 

The ADME data for the drugs classified in drug type (7), drugs with additional dosage forms, should be referred to the guidelines on the bioequivalence studies for generic products (Notification No. 487 of the PAB in 1997). 

Rarely, waivers from human bioequivalence can be granted, although these are only under the most straightforward situations imaginable. The commonest case is that of a generic, intravenous (IV), aqueous solution containing the same active drug at the same concentration. The same concept can be extended to intramuscular (IM) and subcutaneous injectables, when the test and reference products consist of the same type of solution with the same or comparable excipients. This does not extend to topical products, however, when a bioequivalence study must always be carried out if a systemic action is expected. 

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