ICH E6(R3): If E6(R2) Was Already Effective, Why Do We Need R3?-A Medical Writer’s Perspective

By Femi Fajimi | 13 May 2026

(Educational content. No confidential information included.)

Introduction

International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use Good Clinical Practice (GCP) guidelines have long served as the ethical and scientific foundation of modern clinical research. Among these, ICH E6 remains one of the most influential guidelines governing the design, conduct, monitoring, and documentation of clinical trials globally.

When ICH E6(R2) was introduced, it significantly modernised clinical trial oversight by incorporating concepts such as risk-based monitoring, vendor oversight, electronic systems validation, and quality management principles. At the time, many organisations viewed R2 as a major improvement over traditional trial oversight models.

However, clinical research itself continued evolving rapidly. The increasing use of decentralised trial models, digital health technologies, remote assessments, wearable devices, adaptive trial designs, and participant-focused operational strategies began reshaping the clinical trial landscape in ways that extended beyond what E6(R2) originally addressed, raising an important question:

If E6(R2) was already effective, why do we still need E6(R3)? The answer lies not in R2’s failure, but in the ongoing evolution of clinical research itself.

A Brief Look at ICH E6(R1)

Introduced in 1996, ICH E6(R1) established the original framework for Good Clinical Practice and became the global standard for ethical and scientific conduct in clinical trials.

At the time, most studies were:

• paper-based,
• site-centric,
• operationally rigid,
• and is heavily dependent on frequent onsite monitoring.

R1 focused strongly on:

• participant safety,
• informed consent,
• investigator responsibilities,
• source documentation,
• sponsor oversight,
• and data credibility.

The guideline played a critical role in harmonising clinical research practices across regulatory regions and in establishing consistent expectations for sponsors, investigators, and ethics committees worldwide.

However, the clinical trial environment of the 1990s differs substantially from today’s research landscape.

As clinical trials became increasingly global, technology-driven, and operationally complex, newer challenges emerged that the original framework had not fully anticipated. This eventually led to the development of ICH E6(R2), which aimed to modernise GCP for a more digital and risk-based era of clinical research.

How ICH E6(R2) Changed Clinical Research

Finalised in 2016, ICH E6(R2) was introduced to modernise Good Clinical Practice in response to increasing trial complexity, globalisation, and growing reliance on electronic systems.

One of the most significant changes introduced by R2 was the concept of Risk-Based Quality Management (RBQM).

Rather than treating all trial data and processes equally, R2 encouraged sponsors to focus oversight on:

• critical data,
• critical processes,
• and areas presenting the greatest risk to participant safety and trial integrity.

This marked a major shift away from the traditional approach of intensive onsite monitoring and 100% source data verification.

R2 also strengthened expectations surrounding:

• vendor oversight,
• electronic systems validation,
• audit trails,
• data integrity,
• and sponsor accountability.

Importantly, the guideline clarified that sponsors remain responsible for trial quality even when activities are outsourced to CROs or third-party vendors. This became particularly important as outsourcing increased across global clinical development programmes.

The revision also reflected the growing transition from paper-based systems to digital clinical trial environments involving:

• electronic data capture (EDC),
• eTMFs,
• centralised monitoring,
• and remote data review processes.

For many organisations, E6(R2) represented a major advancement in operational efficiency and quality oversight. Risk-based monitoring approaches became widely adopted, and sponsors increasingly integrated structured quality management systems into clinical trial operations.

However, while R2 successfully modernised oversight and monitoring practices, clinical research itself continued evolving beyond traditional operational models. Emerging technologies, decentralised trial approaches, and participant-focused study designs soon introduced challenges that extended beyond the scope of R2 alone.

If E6(R2) Was Effective, Why Do We Need R3?

This is perhaps the most important question surrounding the introduction of ICH E6(R3).

The development of R3 does not suggest that E6(R2) was unsuccessful. In many respects, R2 significantly improved trial oversight, data integrity, and quality management within modern clinical research. However, the pace of innovation in clinical trials continued to accelerate beyond what R2 was originally designed to support.

Modern clinical trials now increasingly involve:

• decentralised trial components,
• wearable technologies,
• remote patient monitoring,
• electronic informed consent,
• adaptive trial designs,
• platform studies,
• real-world data integration,
• and digitally connected health systems.

These developments have transformed how clinical trials are conducted and how participants interact with research.

For example, participants may no longer attend every study visit physically at a research site. Data may be collected remotely through mobile applications, wearable devices, or home healthcare services. Some studies may adapt dynamically based on interim findings, while others may operate across multiple treatment arms under a single master protocol.

Although E6(R2) addressed risk-based oversight and electronic systems, it was still largely rooted in traditional assumptions about how trials are operationally conducted.

ICH E6(R3), therefore, represents a broader philosophical evolution in Good Clinical Practice.

Rather than focusing primarily on procedural compliance, R3 places greater emphasis on:

• proportionality,
• flexibility,
• quality by design,
• critical-to-quality factors,
• and participant-focused trial conduct.

The revision acknowledges that not all trials carry the same level of risk or operational complexity and that oversight approaches should be proportionate to the specific study design and associated risks.

In many ways, R3 shifts the focus from simply ensuring compliance with trial procedures toward designing trials that are scientifically sound, operationally practical, and less burdensome for participants while still maintaining data reliability and participant protection.

The Shift Towards Participant-Centred Clinical Trials

One of the most noticeable differences between ICH E6(R2) and ICH E6(R3) is the stronger emphasis on participant-centred clinical research.

Traditionally, clinical trials were often designed primarily around operational efficiency, site processes, and data collection requirements. While participant safety remained a core priority, the overall participant experience was not always central to trial design decisions.

As a result, many studies became associated with:

• frequent onsite visits,
• complex procedures,
• long travel distances,
• repetitive assessments,
• and a significant administrative burden for participants.

Over time, the industry began recognising that excessive complexity can negatively affect:

• participant recruitment,
• retention,
• protocol adherence,
• data quality,
• and study diversity.

ICH E6(R3) reflects a growing effort to address these challenges by encouraging sponsors to consider whether trial procedures are genuinely necessary, scientifically justified, and proportionate to the study’s objectives.

This participant-focused approach supports the increasing use of:

• remote assessments,
• telemedicine visits,
• home healthcare services,
• wearable technologies,
• electronic informed consent,
• and simplified trial procedures where appropriate.

Importantly, R3 does not reduce expectations for participant protection. Instead, it broadens the concept of participant protection beyond physical safety alone to include accessibility, convenience, and overall trial experience.

This shift is particularly relevant as the industry continues working towards improving diversity and inclusivity in clinical research. Reducing unnecessary burden may help increase participation among individuals who might otherwise face barriers to trial involvement due to geography, mobility limitations, employment responsibilities, or healthcare access challenges.

In this sense, R3 reflects a growing recognition that participant-centred trial design is ethically important. Still, it may also contribute to stronger recruitment, improved retention, and more reliable clinical research outcomes.

Decentralised Trials and Modern Clinical Research

Decentralised Trials and Modern Clinical Research

The increasing adoption of decentralised clinical trial components is one of the major factors driving the transition towards ICH E6(R3).

Traditional clinical trials were largely built around physical research sites, where participants attended scheduled visits for assessments, treatment administration, safety monitoring, and data collection. While this model remains important, advances in digital health technologies have significantly expanded how clinical research can now be conducted.

Modern studies may involve:

• remote patient monitoring,
• wearable devices,
• telemedicine consultations,
• electronic patient-reported outcomes (ePROs),
• home nursing visits,
• and direct-to-patient investigational product delivery.

These approaches became particularly visible during the COVID-19 pandemic, when many sponsors and CROs rapidly adopted remote and decentralised trial strategies to maintain study continuity while reducing unnecessary onsite visits.

As decentralised approaches continue expanding, they introduce operational and regulatory considerations that extend beyond traditional monitoring frameworks.

For example:

• How should remotely collected data be verified?
• How should wearable device data be managed?
• How should participant privacy and cybersecurity risks be addressed?
• How can sponsors maintain oversight across highly digital trial environments?

ICH E6(R3) attempts to provide a more flexible framework that supports these modern trial models while maintaining core GCP principles related to participant safety, data reliability, and scientific integrity.

Importantly, R3 does not promote technology simply for innovation’s sake. Instead, the guideline encourages sponsors to adopt technologies and operational approaches that are proportionate, scientifically justified, and appropriate for the specific study design and participant population.

This reflects an important shift in thinking within clinical research. Rather than expecting all trials to follow the same operational structure, R3 recognises that different studies may require different oversight strategies depending on:

• trial complexity,
• participant risk,
• study objectives,
• and technological requirements.

As decentralised and digitally enabled trials continue evolving, the principles introduced in R3 may increasingly shape how future clinical studies are designed, monitored, and experienced globally.

Are Organisations Beginning to Align with ICH E6(R3) Principles?

Although ICH E6(R3) reflects the evolving direction of modern Good Clinical Practice, implementation across the clinical research industry is likely to occur gradually rather than through immediate operational transformation.

As ICH E6(R3) continues to be implemented across regulatory regions, many existing clinical trial processes and quality systems remain influenced by operational frameworks originally developed under ICH E6(R2). However, several concepts emphasised within ICH E6(R3), including risk-proportionate oversight, participant-centred trial conduct, decentralised trial approaches, and quality-by-design principles, are increasingly reflected in broader discussions surrounding modern clinical research.

In recent years, the clinical trial landscape has seen growing interest in:

• remote and decentralised trial activities,
• electronic informed consent,
• wearable technologies,
• centralised monitoring approaches,
• and digitally enabled participant engagement strategies.

These developments appear broadly consistent with the direction and flexibility encouraged within ICH E6(R3), particularly regarding proportionality, operational adaptability, and participant-focused trial design.

At the same time, implementing R3-related principles may present practical and operational challenges for sponsors, CROs, and research sites. Organisations may need to consider:

• updates to SOPs,
• workforce training,
• technology integration,
• data governance,
• vendor oversight processes,
• and evolving inspection expectations.

The pace of adoption may also vary depending on:

• regulatory region,
• organisational readiness,
• therapeutic area,
• trial complexity,
• and available technological infrastructure.

Rather than representing a complete replacement of existing GCP practices, ICH E6(R3) may be viewed as part of the continuing evolution of clinical research towards more flexible, risk-proportionate, and participant-focused operational models.

Challenges Associated with Implementing ICH E6(R3)

Although ICH E6(R3) introduces greater flexibility and a more participant-focused approach to clinical research, implementation may present practical and operational challenges across the industry.

For many organisations, adopting R3-related principles may involve reassessing existing approaches to:

• quality management,
• monitoring strategies,
• technology integration,
• protocol design,
• and operational oversight.

The increasing use of decentralised and digitally enabled trial activities may also introduce additional considerations relating to:

• data governance,
• cybersecurity,
• interoperability of electronic systems,
• remote oversight,
• and management of large volumes of digital data.

In addition, organisations may need to consider how flexible and risk-proportionate trial conduct can be implemented while still maintaining:

• participant safety,
• data reliability,
• inspection readiness,
• and regulatory compliance.

Another important consideration is the consistency of implementation across different regions and study types. Because clinical trials vary substantially in complexity, risk profile, and operational design, applying proportionate oversight approaches in practice may not always be straightforward.

For example, determining:

• which trial activities are critical-to-quality,
• which procedures are genuinely necessary,
• and how monitoring strategies should be adapted,
• may require substantial cross-functional collaboration between clinical operations, quality teams, statisticians, medical writers, data managers, and regulatory professionals.

The transition towards R3 may therefore involve not only procedural updates, but also broader cultural and operational shifts in how clinical trials are designed, managed, and evaluated across the research lifecycle.

What Could ICH E6(R3) Mean for Medical Writers?

The evolution from ICH E6(R2) to ICH E6(R3) may also influence the role of medical writers within clinical development programmes.

Traditionally, protocol writing and other clinical documents have focused heavily on procedural detail, operational consistency, and regulatory compliance. While these elements remain essential, the increasing emphasis on proportionate trial design and participant-centred research may gradually shape how future study documents are developed.

As decentralised and digitally enabled trial models continue evolving, medical writers may increasingly encounter protocol content relating to:

• remote assessments,
• wearable technologies,
• telemedicine procedures,
• electronic informed consent,
• adaptive trial designs,
• and risk-based operational approaches.

Writers may also play a greater role in helping cross-functional teams communicate complex trial designs in ways that remain:

• scientifically clear,
• operationally feasible,
• participant-focused,
• and regulatorily compliant.

In addition, the stronger emphasis on quality-by-design principles within R3 may encourage earlier collaboration between medical writers and other stakeholders during protocol development. This could involve contributing to discussions surrounding:

• critical-to-quality factors,
• participant burden,
• schedule of assessments,
• and protocol simplification strategies.

As clinical research continues to evolve, medical writing may increasingly extend beyond document preparation alone towards a more integrated role that supports clarity, consistency, and quality throughout clinical development.

Final Thoughts

ICH E6(R3) does not replace the fundamental ethical and scientific principles established in earlier Good Clinical Practice guidance. Instead, it reflects the continuing evolution of clinical research and the need for trial oversight approaches that are flexible, proportionate, and responsive to modern clinical trial environments.

While ICH E6(R2) significantly advanced risk-based oversight, quality management, and sponsor accountability, the increasing use of decentralised trial activities, digital health technologies, and participant-focused operational models has continued reshaping how clinical research is conducted globally.

In this context, ICH E6(R3) may be viewed not as a replacement of previous guidance, but as an effort to adapt longstanding GCP principles to a changing research landscape.

Importantly, the transition towards R3 is unlikely to occur uniformly or immediately across the industry. Implementation will likely continue to evolve as organisations, sponsors, CROs, investigators, and regulatory authorities further interpret and operationalise its principles in real-world clinical trial settings.

Ultimately, the discussion surrounding ICH E6(R3) reflects a broader shift within clinical research, one that increasingly emphasises proportionate oversight, operational flexibility, and participant-focused trial conduct while continuing to uphold participant safety, rights, well-being, and data reliability.

References

1. ICH Website. ICH Harmonised Tripartite Guideline: Guideline for Good Clinical Practice E6(R1). Published May 1, 1996.
2. ICH Website. Integrated Addendum to ICH E6(R1): Guideline for Good Clinical Practice E6(R2). Published November 9, 2016.
3. ICH Website. ICH E6(R3): Guideline for Good Clinical Practice – Step 4 Version. Published January 14, 2025.
4. US Food and Drug Administration. Digital Health Technologies for Remote Data Acquisition in Clinical Investigations: Guidance for Industry, Investigators, and Other Stakeholders. US Department of Health and Human Services; December 2023.
5. European Commission, Heads of Medicines Agencies, European Medicines Agency. Recommendation Paper on Decentralised Elements in Clinical Trials. Version 2. Published October 29, 2025.
6. MHRA Website. Clinical Trials for Medicines: Compliance with ICH E6 Good Clinical Practice (GCP) in the United Kingdom. Gov.uk. Published March 27, 2026. Updated April 28, 2026.
7. TransCelerate BioPharma Inc. Position Paper: Risk-Based Monitoring Methodology. Published 2013.
8. Clinical Trials Transformation Initiative. CTTI Recommendations: Decentralized Clinical Trials. Published September 2018.
9. US Food and Drug Administration. Oversight of Clinical Investigations — A Risk-Based Approach to Monitoring: Guidance for Industry. US Department of Health and Human Services; August 2013.
10. ICH Website. ICH Reflection Paper on GCP Renovation: Modernisation of ICH E8 and Subsequent Renovation of ICH E6. Approved June 2021.