Who is responsible for determining the causality of a serious adverse event in a clinical trial?

The Principal Investigator (PI) is responsible for determining the causality of a serious adverse event (SAE) in a clinical trial. The PI holds the primary responsibility for the conduct of the trial at their site and is tasked with ensuring the safety and well-being of the trial participants. They evaluate the data collected during the trial, including adverse events, in order to assess the relationship between the trial intervention and the events reported.

The PI's expertise allows them to consider clinical relevance, the timing of the event in relation to the treatment administration, and any other potential confounding factors. Given their comprehensive understanding of the study protocol and participant health status, the PI plays a critical role in accurately attributing the SAE to the intervention or determining alternative explanations.

While the study's medical monitor, sponsor, and regulatory affairs officer play important roles in overall trial oversight and compliance, the PI has the direct responsibility and authority to make determinations about causality based on their clinical judgment and the data gathered during the study. This ensures that any necessary actions can be taken swiftly to protect participants and maintain the integrity of the trial.