Pharmacovigilance – how we monitor the safety of medicinal products
Before a new medicinal product is placed on the market, all available information on its safety and efficacy comes only from clinical trials. The conditions under which patients and medicines are studied may not necessarily reflect the way medicines are used in hospitals or outpatient practices following their placement on the market. At the time of granting the marketing authorisation, a relatively low number of patients have been exposed to the product for a limited period of time.
Despite intensive research conducted in animals and during clinical trials in humans, some adverse reactions may be identified only after the product is used by a large number of people. For this reason it is very important to monitor the safety of medicinal products also after their marketing – and this is the subject of pharmacovigilance.
Pharmacovigilance is a process which includes:
- The monitoring of use of medicinal products in everyday clinical practice, so as to be able to identify previously unidentified adverse reactions or a change in the nature of adverse reactions.
- Risk-benefit assessment of medicinal products, which helps to decide what action, if necessary, is essential for a safer use of medicinal products.
- Provision of information to healthcare professionals as well as to patients in order to improve the safe and effective use of medicinal products.
Risks and benefits of medicinal products
In order to consider a medicinal product assafe, the anticipated benefits should prevail over any risk of injury arising from the administration of the product. All medicinal products can cause adverse reactions, yet it is important that in most people using the medicine no serious adverse reactions occur. Information on potential adverse reactions and their possible prevention is provided in the summaries of the product characteristics and package leaflets which are available from the SÚKL's database of medicinal products.
Sources of information in pharmacovigilance
Pharmacovigilance uses information from many sources:
- Spontaneous reporting of adverse reactions from healthcare professionals (link to adverse reactions)
- Clinical trials and epidemiological studies
- Published global medical literature
- Pharmaceutical companies
- Healthcare and population statistics
- Information on the consumption of medicinal products
Regulatory measures
Information from all of the above-mentioned sources is evaluated and may help to identify facts which have not been recognised in the course of clinical trials conducted prior to the placement of the product on the market. Adverse reactions not described to date may be identified, as well as a higher than anticipated frequency of incidence of known adverse reactions (i.e. that they occur more often than originally expected) or a more severe course than currently known. It may also turn out that some patient groups which have not been included in clinical trials are more sensitive to adverse reactions. Any new information is carefully analysed and if necessary, regulatory action is taken to reduce the risk presented by the use of the medicinal product. Regulatory measures result in the change of conditions under which the medicinal product is marketed. It may involve the following:
- Changes to the texts accompanying the medicinal products (SPC and PIL) – amended warnings concerning adverse reactions and, if applicable, their possible prevention
- Restriction of indications for use of the medicinal product
- Change in dosage
- Change in dispensing (e.g. an OTC product may be switched to a prescription-only product)
- In rare cases, where the risks outweigh the benefits, the product may be withdrawn from the market.
SÚKL in its pharmacovigilance activities closely cooperates with the medicines agencies of other Member States of the European Union.
Communication with healthcare professionals and patients
Communication with healthcare professionals and patients represents an essential element of pharmacovigilance. The public as well as professionals need to be advised of adverse reactions to medicinal products. SÚKL provides information in particular through the following channels:
- Updates of texts accompanying products – Summaries of the product characteristics and Package leaflets – if a new adverse reaction has been described.
- Letters sent directly to doctors and/or pharmacists which alert them of possible risks associated with the administration of medicinal products
- SÚKL website, where safety update reports are published
- Publication of information on adverse reactions in the information newsletter Adverse Drug Reactions (Nežádoucí účinky léčiv) (if you would like to receive the Adverse Drug Reaction Information newsletter, please contact the Department of Pharmacovigilance at farmakovigilance@sukl
cz)
