Pharmacovigilance and Drug Safety

A safety database is both a core element of any pharmacovigilance system and a legal pre-requisite for pharmaceutical companies wishing to place a medicine or medicinal product onto any EU/EEA market ^[1]. To enter those markets, each product must first be granted a Marketing Authorisation (MA) by the regulatory authorities ^[1]. The safety database must already be in place and described within the Detailed Description of Pharmacovigilance System (DDPS) accompanying the MA application ^[1]. This article explains key functions of safety databases, to create a better understanding of their overall purpose.

Why have a Safety Database?

Safety databases should allow pharmaceutical companies to rapidly gather relevant information about the medicine or medicinal products in question. There will be information which needs to be supplied to regulatory authorities via statutory electronic reporting and the database must support this. The database must therefore be validated and acceptable to those regulatory authorities. In essence, the database must be entirely suitable to the task, in compliance with Part III of the relevant legislation, Volume 9A of The Rules Governing Medicinal Products in the European Union – Guidelines on Pharmacovigilance for Medicinal Products for Human Use ^[1]. Details of the database are assessed during the application stage for each MA, as they will form part of the DDPS ^[2]. To paint perhaps a more rapidly accessible picture here, the safety database is the tool used to help staff collate and analyse key drug safety data. One example could be any Adverse or Suspected Adverse Event Reports for one particular product. The database will be electronic but not ‘autonomous’: it will not perform tasks without key interaction by highly skilled staff, no matter which process is underway.

Signal Detection

A compliant, suitable Safety Database is able to process data related to signal detection. Signal detection essentially uses data to detect any new patterns or findings. These can be identified by analysing data tables according to principles of statistical disproportion. Upon detection the subsequent course will be variable but can involve action by the regulatory authorities.

Periodic Safety Update Reports Production (PSURs)

Any medicine or medicinal product granted an (EU) MA is legally required to become the subject of post-marketing Periodic Safety Update Reporting. PSURs are always more than an in-house assessment. Presented directly to regulatory authorities, as you might expect whenever drug safety is concerned, they will of course be subjected to an extremely thorough inspection of their contents. A comprehensive database will be able to process the required data in a manner which facilitates the production of PSURs in the appropriate format as far as those authorities are concerned. For example, modern databases integrate regionally-tailored support on regulations.

Statutory Electronic Reporting

Certain safety databases are able to incorporate functionality to file expedited and aggregate reports to regional regulatory authorities. Again, this would always take place with core staff input, rather than becoming any type of scenario where a computer simply somehow ‘spits out’ a report. Electronic reporting will be required within strict time deadlines and differing formats by differing authorities throughout the world. In the EU for example, expedited reporting is obligatory within 15 days of a spontaneous adverse drug reaction case report.

These are just some of the core functions of a suitable safety database, which make it easy to see why it’s one of the pillars of good quality drug safety monitoring. It may be web-based, but whatever the platform it will be electronic. It is not however necessary for pharmaceutical companies to purchase and install a dedicated ‘in-house’ safety database. Instead it is common to find them using commercially available fully compliant products introduced by external pharmacovigilance services firms, who simply provide them with the necessary ongoing support.

References:

1. EMEA. Volume 9A of The Rules Governing Medicinal Products in the European Union – Guidelines on Pharmacovigilance for Medicinal Products for Human Use. 2011. [ONLINE] Available at: http://ec.europa.eu/health/files/eudralex/vol-9/pdf/vol9a_09-2008_en.pdf. [Accessed 22 January 2011].

1. EMEA. Volume 9A of The Rules Governing Medicinal Products in the European Union – Guidelines on Pharmacovigilance for Medicinal Products for Human Use. 2011. Article 2.2.3 d [ONLINE] Available at: http://ec.europa.eu/health/files/eudralex/vol-9/pdf/vol9a_09-2008_en.pdf. [Accessed 22 January 2011].

Signal detection based on spontaneous reporting involves looking for any new patterns or seemingly significant new findings in the safety database. It may be one or more reports showing particularly strong evidence of a previously unknown adverse reaction for that drug, or involving adverse events that are usually caused by drugs, such as aplastic anaemia or toxic epidermal necrolysis. More often, it is a matter of looking for patterns or clusters of reports that stand out from the background. These clusters may be identified by looking at data tables, or – for large databases, such as those held by regulatory authorities or by a company with product with many cases reported – using computerised methods involving statistical disproportion. Examples include the Proportional Reporting Ratio, Bayesian Combination Propagation Neural Network used by the WHO Uppsala Monitoring Centre and the Modified Gamma Poisson Shrinker method used by FDA and MHRA.

Having identified potential tentative signals it is necessary to evaluate them and to consider whether they are real or not. Often, an apparent signal can result just from the disease that the drug is treating – so if a drug is used in patients for the treatment of high blood pressure, it would not be surprising to find reports of high blood pressure itself, and also kidney disease, stroke and heart failure, because these are either contributory or complications of high blood pressure. This is often a difficult process: evaluating signals involves looking at the individual case reports and assessing the strength of causation of the drug in each case. Other sources of safety data are usually also checked at this time – for example, the data from clinical trials and toxicology studies.

It may then be appropriate and necessary to set up a study specifically investigating a particular signal or safety concern. Other possible actions could be to institute a review of the benefits and risks of the product; to suspend or revoke the marketing authorisation; to propose a change to the product information (SPC, labelling); to issue a warning to health professionals in the form of a Dear Health Professional communication; or perhaps just to keep the issue under review. At some point, it may become apparent that the signal was not real, and the issue can be shelved.