Clinical trials are an essential stage in the development of a medicinal product, as they provide the opportunity to assess its efficacy and safety in humans. However, the safety profile of a drug is not established once and for all before a study begins. Instead, safety is continuously monitored throughout the entire clinical development process.
This is where pharmacovigilance plays a crucial role. It is responsible for collecting, analyzing, and interpreting safety data generated during clinical trials, helping to ensure that any potential risks are identified and managed appropriately while the study is ongoing.
The role of pharmacovigilance in clinical trials
During clinical trials, investigational medicinal products are administered to human subjects under controlled conditions and according to predefined study protocols. Nevertheless, it is precisely within this framework that new and important information regarding tolerability and potential risks may emerge.
Pharmacovigilance is responsible for monitoring these aspects in a systematic manner. Its role extends beyond simply collecting reports of adverse events; it contributes to the overall evaluation of the product’s benefit-risk profile throughout the study.
The ultimate objective of pharmacovigilance in clinical research is the protection of study participants. The safety data collected during a trial are not merely descriptive; they can lead to concrete actions such as protocol amendments, updates to safety information, modifications to monitoring procedures, and, in the most significant cases, temporary suspension or termination of the study.
How safety events are classified
Not all events observed during a clinical study carry the same clinical or regulatory significance. For this reason, safety data are categorized into specific classifications that help determine their relevance and the appropriate management approach.
- AE (Adverse Event): Any unfavorable medical occurrence in a participant who has received a medicinal product, regardless of whether it is considered related to the treatment.
- SAE (Serious Adverse Event): An adverse event that results in significant consequences such as death, a life-threatening condition, hospitalization or prolongation of hospitalization, significant disability, or a congenital anomaly.
- ADR (Adverse Drug Reaction): An event for which there is at least a reasonable possibility of a causal relationship with the medicinal product.
- SUSAR (Suspected Unexpected Serious Adverse Reaction): A suspected adverse reaction that is both serious and unexpected based on the existing safety information available for the investigational product.
In addition to clinical events, other relevant safety information may also be considered, including laboratory abnormalities and findings from diagnostic or instrumental examinations.
This classification system enables the rapid identification of critical situations and supports the timely implementation of measures aimed at protecting study participants.
How safety is monitored during a clinical trial
The investigator, who is responsible for conducting the study at the clinical site, identifies, documents, and evaluates clinically relevant events. These events may be detected during scheduled visits, through clinical and diagnostic assessments, or reported directly by study participants.
The investigator assesses the seriousness of the event and its potential relationship to the investigational treatment, then reports it promptly to the sponsor according to protocol requirements.
The sponsor, through its pharmacovigilance function, systematically collects, reviews, and analyzes safety reports received from clinical sites. Safety information is assessed collectively to monitor the medicinal product’s safety profile and identify potential risks. When necessary, the sponsor is also responsible for submitting safety reports to regulatory authorities and ethics committees.
Particularly important is the management of SUSARs. When an event is classified as a SUSAR, an expedited reporting process is triggered. This requires rapid communication to competent authorities and ethics committees within defined regulatory timelines. The purpose of expedited reporting is to ensure that critical safety information is communicated without delay, allowing timely evaluation and, if necessary, immediate corrective action.
Other safety information is collected and analyzed continuously throughout the study and is incorporated into periodic safety reports, such as the Development Safety Update Report (DSUR), which provides a comprehensive overview of the safety profile of the investigational medicinal product.
Conclusions
In summary, pharmacovigilance accompanies every stage of a clinical trial and serves as a safeguard for both quality and participant safety.
Through the continuous monitoring of safety data, pharmacovigilance helps make clinical research more reliable, transparent, and focused on participant protection. Beyond meeting regulatory requirements, it plays a fundamental role in ensuring that decisions throughout drug development are informed by an ongoing assessment of benefits and risks.
References
- ICH E6(R2) – Good Clinical Practice (GCP)
- ICH E2A – Clinical Safety Data Management: Definitions and Standards for Expedited Reporting
- Regulation (EU) No. 536/2014 – Clinical Trials Regulation
- European Medicines Agency (EMA) – Good Pharmacovigilance Practices (GVP)
- FDA – Safety Reporting Requirements for INDs