Medicines and vaccines have transformed the prevention and treatment of diseases. In addition to their benefits, all medicinal products, medical devices and vaccines may also have side effects. Some of the side effects may be undesirable and unexpected. These reactions, though mild in most cases, have potential to cause disability and even death.
As per World Health Organisation (WHO), Pharmacovigilance is the science and activities relating to the detection, assessment, understanding and prevention of adverse effects or any other drug/vaccine related problem.
All medicine before they are authorized for use undergo rigorous testing for safety and efficacy through clinical trials. Clinical trials typically involve small number of selected individuals for a short period of time. Pharmacovigilance process begins with clinical trials that provide data on the benefits and risks of a study drug. If benefits outweigh the risks the manufacturer take steps to gain approval to market the new drug.
However certain side effects may only happen once these products have been used by a heterogenous population. Long term risks with the drug, potential drug interactions, reactions to overdose, drug misuse or abuse information are poorly identified in clinical trials. For this reason ongoing pharmacovigilance is necessary to update the potential risks of medications.
Pharmacovigilance activities involve monitoring investigational medical products and approved drugs to identify new adverse effects, recognise changes in known side effects, assessing benefit-risk ratio to determine if action is required to improve safety.
Good pharmacovigilance will identify the risks within the shortest possible time after the medicine has been marketed and will help to establish or identify risk factors. When communicated effectively, this information allows for intelligent, evidence based prescribing with the potential for preventing many adverse drug reactions. Such information will ultimately help patients to receive optimum therapy at a lower cost.
The goals of pharmacovigilance are;
- To improve patient care and safety in relation to the use of medicines, and all medical and paramedical interventions.
- To improve public health and safety in relation to the use of medicines
- To contribute to the assessment of benefit, harm, effectiveness and risk of medicines, encouraging their safe, rational and more effective (including cost-effective) use
- To promote understanding, education and clinical training in pharmacovigilance and its effective communication to health professionals and the public
Key organizations that play a major collaborative role for PV on a global level are:
the WHO, the ICH, and the Council for International Organizations of Medical Sciences (CIOMS).
There are country-level regulatory agencies such as US-FDA, UK-MHRA, Japan-PMDA, Health Canada, Australia – TGA, China-NMPA, South Korea -MFDS, European Medicines Agency, the Central Drugs Standard Control Organization India, etc,.
These regulators are responsible for ensuring safety, quality, and efficacy of medicines in their country or region, providing regulatory guidelines or legislation, and conducting inspection of pharmaceutical companies.
Pharmacovigilance terms and definitions:
Adverse event (AE): is defined as “An adverse event is any untoward medical occurrence in a patient or clinical-trial subject administered a medicinal product and which does not necessarily have to have a causal relationship with this treatment”.
Adverse drug reaction (ADR), Suspected adverse (drug) reaction: is defined as“A response to a medicinal product which is noxious and unintended and which occurs at doses normally used in man for the prophylaxis, diagnosis or therapy of disease or for the restoration, correction or modification of physiological function”.
Serious Adverse Events (SAEs): are defined as any untoward medical occurrence(s) that at any dose results in death, hospitalisation or prolongation of existing hospitalisation, persistent or significant disability/incapacity or a congenital anomaly or birth defect. Serious Adverse Events (SARs) are serious adverse events but causally related to investigational medicinal products.
Suspected Serious Adverse reactions (SSARs): are any adverse reactions considered consistent with information available about an Investigational medicinal Product (IMP). They must be reviewed at regular intervals to see if the profile of any IMP has changed and a record made of this.
Suspected Unexpected Serious Adverse Reactions (SUSARs): are any serious events suspected to be caused by a medicinal product, but which are not consistent with information about the medicinal product (these are the most serious of events and are subject to expedited reporting procedures)