THE EVOLUTION OF GOOD CLINICAL PRACTICE: A COMPARATIVE REVIEW OF ICH GCP E6 (R2) AND E6 (R3)

Abstract

Good Clinical Practice (GCP) provides the ethical and scientific foundation for conducting clinical trials and safeguarding participant welfare. The transition from ICH GCP E6 (R2) to E6 (R3) represents a significant evolution in response to increasingly complex study designs, digital technologies, and decentralized trial models. These developments require regulatory guidance that remains robust while allowing sufficient flexibility to support innovation. In addition, the globalization of clinical research and the growing involvement of multiple stakeholders have further emphasized the need for harmonized yet adaptable regulatory standards. The aim of this review is to compare ICH GCP E6 (R2) and E6 (R3) and evaluate the practical impact of the updated framework on investigators, sponsors, and other research stakeholders. Specific attention was given to how the revised guidance supports operational efficiency without compromising ethical safeguards or scientific validity. A structured qualitative analysis of both versions was conducted. Key aspects examined included trial design, quality management, data governance, investigator and sponsor responsibilities, monitoring strategies, and participant protection. The review focused on identifying major conceptual shifts and evaluating their significance for contemporary clinical research practice. The analysis demonstrates that ICH GCP E6 (R3) adopts a principle-based, risk-proportionate approach, moving beyond the more prescriptive structure of R2. It prioritizes the identification and management of factors critical to participant safety and data integrity, encouraging sponsors and investigators to tailor processes according to study-specific risks. This approach supports innovative methodologies, including decentralized and hybrid trials, facilitates the integration of digital health technologies, and promotes proactive quality management systems embedded throughout the trial lifecycle rather than relying primarily on retrospective corrective actions. For example, in multicenter oncology trials, monitoring activities may focus on critical safety endpoints and high-risk procedures rather than exhaustive source data verification. Such targeted oversight reduces administrative burden while maintaining scientific rigor and regulatory compliance. Furthermore, R3 provides clearer expectations regarding the validation and oversight of digital systems, the management of diverse data sources, and the maintenance of continuous ethical oversight throughout the trial lifecycle. Overall, ICH GCP E6 (R3) aligns regulatory standards with contemporary clinical research realities, enhancing efficiency, flexibility, and sustained participant protection while advancing innovation in global clinical development.