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Generic Substitution for Brand Name Antiepileptic Drugs: A Survey

Published online by Cambridge University Press:  04 August 2016

A. Guberman*
Affiliation:
Division of Neurology, University of Ottawa, The Ottawa Hospital, General Campus, Ottawa, ON, Canada
Céline Corman
Affiliation:
Division of Neurology, University of Ottawa, The Ottawa Hospital, General Campus, Ottawa, ON, Canada
*
Division of Neurology, University of Ottawa, The Ottawa Hospital, General Campus, 501 Smyth Road, Ottawa, ON, Canada K1H 8L6.
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Abstract:

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Background/Objective:

There are presently 26 different generic preparations for five brand name antiepileptic drugs (AEDs) on the Canadian market with others likely to be released in the near future. The purpose of this review is to examine the basis for the controversy surrounding generic substitution for brand name antiepileptic drugs, to present the results of a survey of neurologists' and patients' attitudes toward generic substitution and to increase neurologists'awareness of the issues.

Methods:

The current federal and provincial regulations pertaining to generic drug approval and substitution are reviewed. Published anecdotal and survey reports of the effectiveness and tolerability of generic substitution for AEDs are reviewed. A pilot questionnaire survey of 83 patients from four adult epilepsy clinics and 46 neurologists from across Canada was undertaken to determine attitudes toward generic substitution.

Results and Conclusions:

Several authors have suggested that some AEDs, particularly those with a narrow therapeutic index, may pose problems with generic substitution. Although generic AEDs are lower in price, possible increased side effects and morbidity and the need for closer monitoring could partially offset the cost savings. The results of our survey highlight significant unawareness of the process of generic substitution among both patients and neurologists and reveal a general level of discomfort among neurologists to prescribe generic AEDs. Further data should be obtained about the potential consequences of generic substitution in epilepsy patients.

Résumé:

RÉSUMÉ:Introduction/Objectif:

Il existe présentement 26 préparations génériques différentes de cinq médicaments anticonvulsivants de marques déposées (MAC) sur le marché Canadien et d'autres sont sans doute sur le point d'être introduits sous peu. Le but de cette revue est d'examiner les fondements de la controverse entourant la substitution de préparations génériques à des médicaments de marques déposées dans le traitement de l'épilepsie, de présenter les résultats d'une enquête sur l'attitude des neurologues et des patients concernant la substitution d'une préparation générique et de susciter une prise de conscience chez les neurologues à ce sujet.

Méthodes:

Les règlements fédéraux et provinciaux actuels concernant l'approbation des préparations génériques et la substitution sont revus. Des rapports anecdotiques et des rapports d'enquêtes publiés sur l'efficacité et la tolérabilité de préparations génériques de MACs sont revus. Une enquête pilote effectuée par questionnaire chez 83 patients de 4 cliniques d'épilepsie pour adultes et chez 46 neurologues à travers le Canada a été effectuée afin de déterminer les attitudes envers la substitution de préparations génériques.

Résultats et Conclusions:

Plusieurs auteurs ont suggéré que la substitution d'une préparation générique de certains MACs, particulièrement ceux qui ont un index thérapeutique étroit, peut poser des problèmes. Bien que les MACs génériques soient moins coûteux, une augmentation possible des effets secondaires et de la morbidité ainsi que la nécessité d'une surveillance plus étroite pourraient réduire partiellement l'épargne au niveau du coût des médicaments. Les résultats de notre enquête soulignent la méconnaissance significative chez les patients et chez les neurologues du processus de substitution d'une préparation générique et révèle un niveau général d'inconfort chez les neurologues dans la prescription de MACs génériques. D'autres données devraient être obtenues sur les conséquences potentielles de la substitution de préparations génériques chez les patients épileptiques.

Type
Original Article
Copyright
Copyright © The Canadian Journal of Neurological 2000

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