Pharmacovigilance history, importance and current status
Pharmacovigilance, a science that studies the adverse effects of medicines, has come a long way since its inception in the 1960’s when the thalidomide disaster occurred. Manufacturers of medicinal products must prove the safety and efficacy of their products to obtain regulatory approval and place their product on the market. Side effects of medicines identified in clinical trials are now included in the drug label, along with indications, contraindications, interactions with other drugs and conditions of use.
Specific population subgroups such as people with multiple co-morbidities and co-medications, liver impairment, or kidney damage are often excluded from clinical trials and only become exposed to these medications after they reach the market. Physicians do not have to strictly adhere to the labeled indications and can prescribe any approved drug to their patients who, according to their professional judgment, are likely to benefit from its use, considering their overall condition and other medications in the context of individual care. However, things do not always work out. Patients may develop side effects that make them stop taking the drug altogether or force them to switch to a different medication, or the drug may have no effect at all. Newly administered drugs may interact with other drugs the patient has been taking for other disorders, or the patient may be metabolizing the pharmaceutical ingredient slower than most of the people studied in clinical trials and become overdosed due to accumulation of the drug or its metabolite in their system.
These instances of untoward effects of medications in real-life use are collected through post-market surveillance system all manufacturers must implement to keep their drugs on the market. Manufacturers, or precisely market authorization holders, have the obligation to collect, process, analyze and report these instances of adverse drug effects to regulatory authorities. The Food and Drug Administration (FDA) then imports the case reports received from manufacturers and other sources into the FDA Adverse Event Reporting System (FAERS) database. Because physicians and consumers have no obligation to report adverse effects to the FAERS database, most of the reports, about 95%, come from the industry. The FAERS database is currently the most important source of data used for the detection of signals of adverse effects of medications. Other sources of data include scientific literature and studies conducted after approval to study specific concerns or to prove the utility of approved drugs for new indications.
The current drug surveillance system was designed in the 1960s and the first reports in the FAERS database date back to 1968. Most of the major technological advances implemented to date concern methods of detection of safety signals utilizing data contained in the database and making sense of the information in the context of other scientific evidence. Information technology is one of the most rapidly developing and expanding fields of knowledge that profoundly changed practices in industry and commerce. Post-market surveillance of marketed drugs is no exception. The volume of data has been steadily increasing, and the costs of doing things the old way have been steadily rising. New technologies in informatics enable the development of methods that would have been unimaginable mere decade ago, let alone when the current system was created. New concepts and technologies in pharmacovigilance are an exciting opportunity to bring the field to the next level.