For many sponsors, sustainability is no longer a peripheral consideration. Environmental, Social and Governance (ESG) commitments and corporate net-zero targets are now influencing how clinical trials are designed and delivered, placing operational models such as site monitoring under increasing scrutiny.
Importantly, on-site and remote visits are only one component of clinical trial monitoring which encompasses the overall oversight of study conduct, including centralized data review, risk-based processes, and site-level activities. However, from a sustainability perspective, on-site monitoring strategies represent one of the most immediate and controllable levers sponsors can pull to minimize the carbon footprint of a clinical trial.
The Impact of On-Site Visits
Monitoring remains essential to protecting participants and ensuring data integrity, but traditional travel-intensive models contribute significantly to a study’s environmental footprint. Approximately 76 000 new trials were registered on WHO’s International Clinical Trials Registry Platform in 2023, each producing an estimated 80–2000 tons of emissions (1, 2). Even at the lower end of the estimates, these numbers are significant: 80 tons is equivalent to driving a car 12 times around the planet.
A primary contributor to this footprint is the frequent on-site visits, required by Clinical Research Associates (CRAs). Flights, trains, rental cars, taxis, and hotel stays associated with monitoring visits can generate substantial greenhouse gas emissions.
Linical supports sponsors in designing monitoring strategies that are fit for purpose, compliant, and proportionate to study risk. By combining remote, hybrid, and on-site approaches where appropriate, Linical helps eliminate unnecessary travel while maintaining focus on trial quality outcomes. While the conceptual benefits of remote monitoring are increasingly accepted, its measurable environmental impact is what makes it strategically compelling.
Importantly, these sustainability gains are achieved not by cutting oversight, but by applying it more intelligently. Risk-based monitoring ensures that critical data and key risk areas remain the focus, maintaining, and in many cases improving, overall trial quality.
Quantifying the Carbon Savings of Traditional vs Remote Models
While data monitoring is an essential part of all trials to ensure validity, trial-specific travel for the purposes of on-site monitoring contributes heavily to trial-associated emissions. Transitioning clinical trials to a remote format dramatically reduces operational emissions. Organizations analyzing activity-based data have calculated major sustainability returns by shifting to virtual and risk-based models.
Transportation and Logistics
In traditional trial models, CRAs travel to investigative sites every 4 to 8 weeks. This travel accounts for an estimated 35% to 50% of a trial’s total operational carbon footprint (3). Transitioning to a hybrid or fully remote monitoring framework cuts physical site visits by an average of 23% (4), directly lowering travel-related greenhouse gas emissions.
Paper and Resource Consumables
Traditional on-site monitoring requires significant paper-based documentation, including regulatory binders, source worksheets, and printed medical records for manual verification. Adopting remote SDV (rSDV) eliminates physical printing, resulting in an estimated 70% decrease in trial-related paper waste (5) and lower emissions from document transport and shredding services.
Site Utility Overhead
Maintaining dedicated workspace, power, and lighting for visiting CRAs adds to a clinical site's energy footprint. Remote monitoring allows research facilities to optimize their physical space, lowering localized utility consumption by up to 28% (2) through shared administrative setups.
Linical’s CRA teams have extensive experience implementing remote and hybrid monitoring approaches while maintaining the quality standards expected in traditional monitoring models. For sponsors, this translates directly into lower monitoring costs and more efficient deployment of CRA resources. These reductions are not incidental; they are a direct outcome of risk-based monitoring approaches that eliminate non-core activities. By focusing oversight on critical data and processes, sponsors naturally lessen the need for frequent on-site visits, creating a clear link between quality-focused design and environmental impact.
Beyond reductions in travel-related emissions, a comprehensive assessment must also consider the carbon impact of digital infrastructure.
- Data Center Energy Consumption: Hosting clinical trial infrastructure on cloud networks relies on global data centers. Global data centers collectively consume immense amounts of electricity, averaging an implicit carbon intensity of 395.65 g of CO₂ per kWh.
- Device Manufacturing: Supplying monitors, site staff, and decentralized patients with dedicated tablets or ePRO (Electronic Patient-Reported Outcomes) devices adds an upfront manufacturing carbon cost.
Nevertheless, in many trial settings, the carbon savings associated with decreased air and vehicle travel are likely to outweigh the additional electricity footprint of cloud-based systems, particularly where digital infrastructure is used efficiently. Sponsors can further optimize this balance by hosting clinical data in regions powered by high proportions of carbon-free energy.
Aligning Remote Monitoring with ICH E6(R3) and E8(R1)
These guidelines reinforce that monitoring should be understood as a comprehensive oversight system, in which different methods (centralized, remote, and on-site) are applied proportionately based on study risk.
ICH E8(R1) highlights the importance of identifying the factors that are critical to trial quality from the outset of study design. ICH E6(R3) builds on this by encouraging proportionate trial management, appropriate use of technology, and risk-based quality management across the trial lifecycle.
While not explicitly framed as sustainability guidance, the principles of quality by design and risk-proportionate oversight inherently support more efficient, less resource-intensive trial delivery.
Linical helps sponsors translate ICH E6(R3) and E8(R1) principles into practical monitoring strategies that not only ensure compliance and quality but also deliver measurable reductions in trial-related environmental impact.
Implementation Challenges and Regulatory Hurdles
However, sustainability gains alone are not sufficient. Implementation must also stand up to regulatory and operational realities. While perceived barriers to remote monitoring remain, these are best viewed as design considerations rather than obstacles. With the right expertise, they can be systematically addressed. Linical’s Regulatory and Legal teams support sponsors in navigating local requirements, data privacy considerations, and study-specific feasibility factors to enable effective trial delivery.
The CRAs cannot simply view uncensored patient records from their home office. Regulatory frameworks, such as Europe's General Data Protection Regulation (GDPR), place strict constraints on remote clinical data access. To maintain patient confidentiality, sponsors must implement advanced digital systems that strictly limit access to verified trial participants. In practice, successful implementation depends on addressing several site level operational considerations outlined below.
|
Consideration |
Why it Matters |
Practical Response |
|
Data Privacy |
Remote access to source data must comply with applicable privacy and confidentiality requirements. Redacting Protected Health Information before remote viewing is time-consuming for site staff. |
Use secure systems, access controls, redaction processes, and documented data-access procedures.
|
|
System Interoperability |
Clinical sites often use different electronic health record systems that may not be interoperable. |
Assess system readiness during start-up and define practical workflows for each site. |
|
Site Burden |
Uploading physical documents for remote review increases workloads for local site staff. |
Apply targeted review focused on critical data and key processes. |
|
Local Feasibility |
Remote SDV may not be permitted or practical in every country, region, or site. |
Use country- and site-level feasibility checks and apply hybrid monitoring where required. |
However, remote SDV cannot be applied in all locations or study settings. Local regulations, ethics committee expectations, institutional policies, data privacy requirements, electronic health record access limitations, and site infrastructure may restrict or prevent remote access to source documents. For this reason, remote monitoring and rSDV should be implemented as part of a flexible, risk-based monitoring strategy, with remote review used where feasible and on-site monitoring maintained where required.
Sustainability improvements are not achieved simply by replacing on-site visits with remote ones, but by redesigning how clinical trials are overseen. This ensures that monitoring activity is proportionate, targeted, and aligned with what matters most for trial quality. As sustainability targets become increasingly embedded in corporate strategy, remote and risk-based monitoring will play a central role in improving the environmental footprint of clinical trials. Sponsors that act now, supported by experienced partners such as Linical, will be best positioned to deliver trials that are not only compliant and efficient but aligned with long-term sustainability goals without compromising quality.
References:
- Lyle K, Dent L, Bailey S, et al. Carbon cost of pragmatic randomised controlled trials: retrospective analysis of sample of trials. BMJ. 2009
- Clinical trials and environmental sustainability. Review of key considerations to develop climate change mitigation and adaptation strategies. World Health Organization. 2025
- Bruno Laviolle. Evaluating the Environmental Impact of Clinical Research: A Full LifeCycle Analysis of a French Academic Randomised Clinical Trials. Fundam Clin Pharmacol, April 2026
- Michael J. Cohen. How much does a clinical research associate impact a company’s carbon footprint? More than you might think!. Drug discovery and Development. 2024
- Tunir Das. Conducting Sustainable Clinical Trials- A step in the right direction. 2024
Author:
Angel Perez Romero PhD
Director, Clinical Operations