The International Council for Harmonisation E6 (R3) revision and its impact on clinical research practice: A narrative review

The International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH), established in April 1990, has released an updated version of its ICH E6 guidelines for Good Clinical Practice (GCP). This new version, ICH E6 (R3), replaces ICH E6 (R2) and introduces major changes promoting innovation across all stages of clinical trials, from planning to reporting. These updates enhance flexibility, inclusivity, risk management, and integration of modern technologies, ensuring ethical conduct and data integrity. Released in January 2025, E6 (R3) focuses on patient safety, advanced data management, transparency through public trial registration and result sharing, and more efficient, adaptable trial designs. At the same time, it presents challenges such as the need for comprehensive staff training and integration of digital health tools. We conducted a literature search using ScienceDirect, PubMed, and Google, along with ICH resources, to identify relevant publications. This narrative review, written in accordance with ICH GCP E6 (R3), emphasizes the key updates, including a risk-based approach that prioritizes patient safety and data quality, the use of electronic systems, decentralized and remote monitoring methods, and strengthened roles for investigators, sponsors, ethics committees, and regulators. Overall, ICH GCP E6 (R3) brings transformative changes that foster innovation at every phase of clinical trials. By promoting patient-centered approaches, fostering innovation, and reinforcing accountability, the guideline offers a framework for safer, faster, and more reliable trials. Effective implementation will depend on training, technological adaptation, and sustained collaboration among stakeholders.