Guy Demol - 30 Nov 2021
What is pharmacovigilance?
Medicines and vaccines have transformed the prevention and treatment of diseases. Specifically, for vaccines, due to large scale vaccination worldwide, potentially severe, highly disabling and even deadly infectious diseases have either been almost eliminated (such as poliomyelitis) or greatly reduced (such as measles). Yet, in addition to their benefits, medicinal products, including vaccines, may also have side effects (also called adverse effects).
Pharmacovigilance can be defined as the science and activities relating to the detection, assessment, understanding and prevention of adverse effects or any other medicine-related problem.
All vaccines (or any medicine) undergo rigorous testing for safety and efficacy through clinical studies before they are authorized for use by Health Authorities, such as the European Medicines Agency (EMA). Although vaccines are typically studied in many thousands of persons before such authorisation, some side effect can be very rare and may therefore not have been detected in clinical studies and only emerge when millions of people are vaccinated.
Pharmacovigilance ensures that the safety of vaccines is monitored while they are in use in routine clinical practice and allows to put in place the required measures to minimise any risk detected.
How does the process work?
Both pharmaceutical companies and health authorities have comprehensive safety monitoring and risk management (pharmacovigilance) systems in place.
These systems ensure that health care providers and vaccinees (or patients) can report possible side effects, either by phone or other, electronic, means. In addition to such spontaneously reported possible side effects, for many (new) vaccines large scale studies are conducted after approval. This allows to further systematically study the safety in a large population in real life circumstances.
All reports from these different sources are collected in databases, reviewed, and assessed individually and in aggregate. If such analyses show unusual effects, experts take even a closer look. This can lead to introducing any necessary mitigating actions, such as informing doctors and patients on risk factors for certain side effects or change how and for whom the medicine is prescribed or the vaccine is administered.
Note that a lot of clear and reliable information on pharmacovigilance can be found on the website of the European Medicines Agency (EMA) and public health organizations such as the WHO.
How are pharmaceutical companies involved in pharmacovigilance?
Pharmaceutical companies have a large amount of safety data on their products.
Initially these data are provided by the clinical studies conducted to evaluate the efficacy and safety of the medicinal product. These studies provide typically the basis for the health authorities to approve the product for larger scale use. Yet, these data are continuously complemented after the approval of the medicine. Companies are legally obliged to have comprehensive safety monitoring and risk management (pharmacovigilance) systems in place. Such a system is operated by trained professional staff, located in the countries and in headquarters. This ensures that health care providers and patients (or vaccinees) can report possible side effects either by phone or other means, in their own language. Such reports and those from large scale studies conducted after approval of the product are collected, analyzed and reported rapidly to the health authorities. Based upon these analyses, companies, in collaboration with health authorities, introduce any necessary actions to minimize risks, such as informing doctors and patients on risk factors for certain side effects or change how and for whom the medicine is prescribed or the vaccine is administered.
How do you ensure that all side effects are reported?
The patient leaflet provides contact information to report possible side effects. In addition, the websites of pharmaceutical companies and health authorities also provide such information. In several countries user friendly apps are being deployed to facilitate reporting with a smartphone. Through all these means spontaneous reporting of possible side effects is encouraged.
How is real world evidence used in pharmacovigilance?
The basis of pharmacovigilance is the data collected either spontaneously from health care providers and patients (or vaccinees) or from large scale studies conducted in a real-life setting. These data are collected, carefully assessed and used to inform all stakeholders on the side effects of medicines. As such, these data sources constitute real world evidence.
How has innovation improved pharmacovigilance?
Over the years several forms of innovations have improved pharmacovigilance: technological and methodological innovations on the one hand and improvements of the legal requirements and guidelines issued by health authorities and public health organisations on the other hand. Technological innovations are for example apps for mobile devices allowing fast and easy reporting of side effects. Over the years also new methodological aspects of analysing data (for example statistical methods) and innovative study designs to conduct real life studies have emerged.
The use of data captured for other purposes (sometimes referred to as ‘big data’ such as registries of patients with a particular disease or health insurance data) has provided means to study the safety profiles of medicines and vaccines. And finally, also the introduction of a sound legal basis and detailed guidelines by national and supra-national (EU) authorities have contributed to advance pharmacovigilance.