Quality Assurance of Pharmaceuticals - A Compendium of Guidelines and Related Materials - Volume 1
(1997; 248 pages) [French] Ver el documento en el formato PDF
Índice de contenido
Abrir esta carpeta y ver su contenidoIntroduction
Abrir esta carpeta y ver su contenido1. National drug regulation
Cerrar esta carpeta2. Product assessment and registration
Ver el documentoGuidelines for the assessment of herbal medicines1,2
Abrir esta carpeta y ver su contenidoStability of drug dosage forms1
Abrir esta carpeta y ver su contenidoGuidelines for stability testing of pharmaceutical products containing well established drug substances in conventional dosage forms1
Cerrar esta carpetaMultisource (generic) pharmaceutical products: guidelines on registration requirements to establish interchangeability1
Ver el documentoIntroduction
Ver el documentoGlossary
Abrir esta carpeta y ver su contenidoPart One. Regulatory assessment of interchangeable multisource pharmaceutical products
Abrir esta carpeta y ver su contenidoPart Two. Equivalence studies needed for marketing authorization
Cerrar esta carpetaPart Three. Tests for equivalence
Ver el documento10. Bioequivalence studies in humans
Ver el documento11. Pharmacodynamic studies
Ver el documento12. Clinical trials
Ver el documento13. In vitro dissolution
Ver el documentoPart Four. In vitro dissolution tests in product development and quality control
Ver el documentoPart Five. Clinically important variations in bioavailability leading to non-approval of the product
Ver el documentoPart Six. Studies needed to support new post-marketing manufacturing conditions
Ver el documentoPart Seven. Choice of reference product
Ver el documentoAuthors
Ver el documentoReferences
Ver el documentoAppendix 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)
Ver el documentoAppendix 2. Explanation of symbols used in the design of bioequivalence studies in humans, and commonly used pharmacokinetic abbreviations
Ver el documentoAppendix 3. Technical aspects of bioequivalence statistics
Abrir esta carpeta y ver su contenido3. Distribution
Abrir esta carpeta y ver su contenido4. The international pharmacopoeia and related activities
Abrir esta carpeta y ver su contenido5. Basic tests
Abrir esta carpeta y ver su contenido6. Laboratory services
Abrir esta carpeta y ver su contenido7. International trade in pharmaceuticals
Abrir esta carpeta y ver su contenido8. Counterfeit products
Abrir esta carpeta y ver su contenido9. Training
Ver el documentoSelected WHO publications of related interest
Ver el documentoBack cover
 
12. Clinical trials

For certain drugs and dosage forms (see example (e), p. 72) plasma concentration time-profile data are not suitable for use in assessing equivalence between two formulations. While pharmacodynamic studies can sometimes be an appropriate tool for establishing equivalence (see section 11), in other instances this type of study cannot be performed because of a lack of meaningful and measurable pharmacodynamic parameters; a comparative clinical trial must then be performed in order to demonstrate equivalence between two formulations. In such a clinical trial, the same statistical principles will apply as in bioequivalence studies. The number of patients to be included in the study will depend on the variability of the target parameters and the acceptance range, and is usually much higher than that required in bioequivalence studies.

The methodology to be used in establishing equivalence between pharmaceutical products by means of a clinical trial in patients in which there is a therapeutic end-point has not yet been discussed as extensively as that used in bioequivalence trials. However, the following are important and need to be defined in the protocol:

(a) The target parameters; these are usually relevant clinical end-points from which the intensity and the onset, if applicable and relevant, of the response can be derived.

(b) The size of the acceptance range; this must be defined on a case-by-case basis, taking into consideration the specific clinical conditions, for example the natural course of the disease, the efficacy of available treatments and the chosen target parameter. In contrast to bioequivalence studies (where a conventional acceptance range is used), the size of the acceptance range in clinical trials cannot be based on a general consensus on all the therapeutic classes and indications.

(c) The statistical method used; this is currently the confidence interval approach, the main concern being to rule out the possibility that the test product is inferior to the reference pharmaceutical product by more than the specified amount. A one-sided confidence interval (for efficacy and/or safety) may therefore be appropriate. The confidence intervals can be derived by either parametric or non-parametric methods.

Where appropriate, a placebo leg should be included in the design, and it is sometimes appropriate to include safety end-points in the final comparative assessments.

Ir a la sección anterior Ir a la siguiente sección
 

Última actualización: le 3 mayo 2013