Which pharmacovigilance for vaccines?

Vaccines are not separate health products but anti-infectious medicines administered for the large part prophylactically and for which the effect is immunological and not pharmacological. They should be evaluated by the usual methods of clinical pharmacology and pharmacovigilance, taking into account certain specificities (mechanism of action, manufacture, frequent administration to healthy subjects, particular recommendations, etc.). Experience from some vaccination campaigns have revealed insufficiencies notably in data collection allowing evaluation of the interest of a vaccine to public health, its relevance to the recent epidemiology of the disease in question and long-term security. The absence of data can generate fear in the general population that is broadcast by anti-vaccination lobby. For a more optimal pharmacovigilance of vaccines, it is necessary to: (i) improve the coherence between the evaluating authorities; (ii) set up, in addition to the usual risk management plan, an active microbiological and epidemiological surveillance and to follow up exposed populations; (iii) have programmes of education of the medical community regarding vaccination and health education for the general public.

[Not Available]. / Quelle pharmacovigilance pour les vaccins ?

Le vaccin est un médicament biologique (le plus souvent anti-infectieux) administré dans un but le plus souvent préventif, dont l'effet n'est pas pharmacologique mais immunologique. Il doit être évalué par les techniques habituelles de la pharmacologie clinique et de la pharmacovigilance, mais en tenant compte de ses particularités (mécanisme d'action, fabrication, administration le plus souvent à des sujets sains, modalités de prescription particulières avec des recommandations mises à jour régulièrement, protection à la fois individuelle et collective, etc.). Quelques expériences de campagnes vaccinales ont révélé des insuffisances dans l'obtention des données permettant d'évaluer l'intérêt de santé publique d'un vaccin, son adaptation à l'épidémiologie récente de la maladie et sa sécurité d'emploi à long terme. L'absence de données peut générer des craintes relayées par les ligues anti-vaccinales. Pour une meilleure pharmacovigilance des vaccins, il est nécessaire : (i) d'améliorer la cohérence entre les instances d'évaluation, même si des efforts ont été récemment faits ; (ii) de compléter les plans de gestion de risque par une surveillance microbiologique et épidémiologique active et par l'obtention des données nécessaires au suivi de pharmacovigilance des populations exposées ; (iii) d'assurer l'enseignement sur la vaccination au sein de la communauté médicale, ainsi que l'éducation à la santé pour les populations.

Which Pharmacovigilance for Vaccines?

Vaccines are not separate health products but anti-infectious medicines administered for the large part prophylactically and for which the effect is immunological and not pharmacological. They should be evaluated by the usual methods of clinical pharmacology and pharmacovigilance, taking into account certain specificities (mechanism of action, manufacture, frequent administration to healthy subjects, particular recommendations, etc.). Experience from some vaccination campaigns have revealed insufficiencies notably in data collection allowing evaluation of the interest of a vaccine to public health, its relevance to the recent epidemiology of the disease in question and long-term security. The absence of data can generate fear in the general population that is broadcast by anti-vaccination lobby. For a more optimal pharmacovigilance of vaccines, it is necessary to: (i) improve the coherence between the evaluating authorities; (ii) set up, in addition to the usual risk management plan, an active microbiological and epidemiological surveillance and to follow up exposed populations; (iii) have programmes of education of the medical community regarding vaccination and health education for the general public.

[Surveillance of the safety of intravesical BCG therapy in France: quantitative analysis of serious adverse events notified over a period of five years]. / Suivi de la tolérance de la BCG thérapie endovésicale en France: analyse quantitative des évènements indésirables graves notifiés sur cinq ans.

Intravesical BCG therapy remains the first-line prophylactic treatment for recurrent superficial bladder tumours. However, the safety of this drug requires close and rigorous surveillance due to rare, but sometimes serious complications reported after treatment. A quantitative analysis of serious adverse events (SAE) notified in France since marketing of BCG for intravesical immunotherapy (Connaught strain) and over a five-year period (September 1996-September 2001) revealed the following results: During this period, 158 SAEs were spontaneously reported to the Aventis Pasteur Central Pharmacovigilance Department. Of these 158 SAEs, 17 were local, 20 were regional and 121 were systemic. 64% of the 121 systemic SAEs were attributed to suspected BCG infection, 24% consisted of immune disorders and 12% were of unknown origin. Estimation of the SAE notification rate over this 5-year period was 0.37 SAE per 100 treated 100 patients. A tendency towards a lower SAE notification rate has been observed over the last two years. This tendency is concomitant with an information campaign on this drug. A continuing effort by prescribers to report adverse events of BCG-IT and strict compliance with precautions should continue to improve the safety profile of this drug.

The Brighton Collaboration: addressing the need for standardized case definitions of adverse events following immunization (AEFI).

UNLABELLED: To further scientific progress of immunization safety, comparability of data from clinical trials and surveillance systems is essential. Comparability requires the availability of standardized case definitions for adverse events following immunization (AEFI) and guidelines for case determination, recording and data presentation. METHOD: International collaborative working groups, consisting of professional volunteers from developed and developing countries, conduct systematic literature reviews to develop 50-100 AEFI definitions. Case definitions are finalized after a comment period by a reference group consisting of organizations concerned with immunization safety, and will be disseminated via the world-wide-web and other means for free world-wide use. RESULTS: Literature reviews yielded substantial diversity in data collection and presentation. We have developed standardized case definitions together with guidelines for use in clinical trials and surveillance systems. CONCLUSIONS: Diversity in safety methods leads to considerable loss of scientific information. We have built the necessary international network of currently about 300 participants from patient care, public health, scientific, pharmaceutical, regulatory and professional organizations to develop and assess standardized AEFI case definitions and guidelines. Evaluation studies, global implementation, ongoing definition development and a continuously growing network will be essential for the success of the collaboration.