What is an Investigator Initiated Study (IIS)?
An Investigator Initiated Study (IIS), also known as an Investigator-Initiated Trial (IIT), is a clinical trial initiated and conducted by the investigator rather than by a pharmaceutical company or a commercial sponsor. In this model, the investigator assumes the role of the study sponsor, which means they are responsible for the scientific, regulatory, organizational, and ethical aspects of the study.
The key feature of an Investigator Initiated Study is that the research question stems from the investigator's clinical practice or scientific interests. IIS often focus on new indications for existing therapies, optimizing treatment regimens, comparing standard therapies, or studying patient populations that are not covered by commercial trials. As a result, these studies play a crucial role in advancing medical knowledge and real-world clinical practice.
Although IIS may be funded or supported by pharmaceutical companies, grant providers, or academic institutions, the investigator or the scientific unit remains the sponsor. This has significant regulatory implications — the investigator is responsible for protocol preparation, obtaining approval for the study, managing safety, data quality, reporting, and archiving documentation.
One of the main challenges of Investigator Initiated Studies is the complexity of sponsor responsibilities. Investigators often have extensive clinical experience but may not have the operational, regulatory, and quality infrastructure that large commercial sponsors possess. Gaps in this area can lead to delays, data quality issues, or difficulties during the publication phase.
On the other hand, IIS offer significant flexibility in study design and the opportunity to conduct research of high scientific value that may not align with pharmaceutical companies' product development strategies. Increasingly, these studies are being conducted with the support of experienced CROs, which take over some operational responsibilities, ensuring regulatory compliance and high-quality implementation.
From the perspective of the healthcare system, Investigator Initiated Studies are an important complement to commercial research, providing data relevant to everyday clinical practice. Well-planned and professionally conducted IIS can have a real impact on treatment standards, clinical recommendations, and therapeutic decisions.
If you are planning an Investigator Initiated Study and want to ensure that your study will be conducted in accordance with regulatory requirements and the highest quality standards, contact us — we will support you at every stage of your project.
