Quality Assurance of Pharmaceuticals - A Compendium of Guidelines and Related Materials - Volume 1
(1997; 248 pages) [French] View the PDF document
Table of Contents
Open this folder and view contentsIntroduction
Open this folder and view contents1. National drug regulation
Close this folder2. Product assessment and registration
View the documentGuidelines for the assessment of herbal medicines1,2
Open this folder and view contentsStability of drug dosage forms1
Open this folder and view contentsGuidelines for stability testing of pharmaceutical products containing well established drug substances in conventional dosage forms1
Close this folderMultisource (generic) pharmaceutical products: guidelines on registration requirements to establish interchangeability1
View the documentIntroduction
View the documentGlossary
Open this folder and view contentsPart One. Regulatory assessment of interchangeable multisource pharmaceutical products
Open this folder and view contentsPart Two. Equivalence studies needed for marketing authorization
Open this folder and view contentsPart Three. Tests for equivalence
View the documentPart Four. In vitro dissolution tests in product development and quality control
View the documentPart Five. Clinically important variations in bioavailability leading to non-approval of the product
View the documentPart Six. Studies needed to support new post-marketing manufacturing conditions
View the documentPart Seven. Choice of reference product
View the documentAuthors
View the documentReferences
View the documentAppendix 1. Examples of national requirements for in vivo equivalence studies for drugs included in the WHO Model List of Essential Drugs (Canada, Germany and the USA, December 1994)
View the documentAppendix 2. Explanation of symbols used in the design of bioequivalence studies in humans, and commonly used pharmacokinetic abbreviations
View the documentAppendix 3. Technical aspects of bioequivalence statistics
Open this folder and view contents3. Distribution
Open this folder and view contents4. The international pharmacopoeia and related activities
Open this folder and view contents5. Basic tests
Open this folder and view contents6. Laboratory services
Open this folder and view contents7. International trade in pharmaceuticals
Open this folder and view contents8. Counterfeit products
Open this folder and view contents9. Training
View the documentSelected WHO publications of related interest
View the documentBack cover


The definitions given below apply specifically to the terms used in this guide. They may have different meanings in other contexts.


The rate and extent of availability of an active drug ingredient from a dosage form as determined by its concentration-time curve in the systemic circulation or by its excretion in urine.


Two pharmaceutical products are bioequivalent if they are pharmaceutically equivalent and their bioavailabilities (rate and extent of availability), after administration in the same molar dose, are similar to such a degree that their effects can be expected to be essentially the same.

dosage form

The form of the completed pharmaceutical product, e.g. tablet, capsule, elixir, injection, suppository.

therapeutic equivalence

Two pharmaceutical products are therapeutically equivalent if they are pharmaceutically equivalent and after administration in the same molar dose their effects, with respect to both efficacy and safety, will be essentially the same, as determined from appropriate studies (bioequivalence, pharmacodynamic, clinical or in vitro studies).

generic product

The term “generic product” has somewhat different meanings in different jurisdictions. In this document, therefore, use of this term is avoided as much as possible, and the term “multisource pharmaceutical product” (see definition below) is used instead. Generic products may be marketed either under the nonproprietary approved name or under a new brand (proprietary) name. They may sometimes be marketed in dosage forms and/or strengths different from those of the innovator products. However, where the term “generic product” has had to be used in this document, it means a pharmaceutical product, usually intended to be interchangeable with the innovator product, which is usually manufactured without a licence from the innovator company and marketed after the expiry of patent or other exclusivity rights.

innovator pharmaceutical product

Generally, the innovator pharmaceutical product is that which was first authorized for marketing (normally as a patented drug) on the basis of documentation of efficacy, safety and quality (according to contemporary requirements). When drugs have been available for many years, it may not be possible to identify an innovator pharmaceutical product.

interchangeable pharmaceutical product

An interchangeable pharmaceutical product is one which is therapeutically equivalent to a reference product.

multisource pharmaceutical products

Multisource pharmaceutical products are pharmaceutically equivalent products that may or may not be therapeutically equivalent. Multisource pharmaceutical products that are therapeutically equivalent are interchangeable.

pharmaceutical equivalence

Products are pharmaceutical equivalents if they contain the same amount of the same active substance(s) in the same dosage form; if they meet the same or comparable standards; and if they are intended to be administered by the same route. However, pharmaceutical equivalence does not necessarily imply therapeutic equivalence as differences in the excipients and/or the manufacturing process can lead to differences in product performance.

reference product

A reference product is a pharmaceutical product with which the new product is intended to be interchangeable in clinical practice. The reference product will normally be the innovator product for which efficacy, safety and quality have been established. Where the innovator product is not available, the product which is the market leader may be used as a reference product, provided that it has been authorized for marketing and its efficacy, safety and quality have been established and documented.

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