Key Takeaways
- Precision Medicine: Genetic testing streamlines clinical trials by identifying specific genetic variations that influence treatment response and disease susceptibility.
- US Regulation: The FDA oversees Laboratory Developed Tests (LDTs) and In Vitro Diagnostic (IVD) tests, while CMS regulates labs via CLIA guidelines.
- UK Compliance: Post-Brexit, the MHRA oversees regulations, requiring the UKCA mark for genetic tests used in research or direct-to-consumer markets.
- EU Standards: The In Vitro Diagnostic Regulation (IVDR) harmonizes standards across member states, utilizing the CE marking to indicate conformity.
- Strategic Balance: Global regulatory frameworks aim to foster medical innovation while maintaining rigorous safety and analytical validity standards.
Genetic tests in clinical trials
In genetically stratified trials, testing is not an optional or supplementary step. It determines eligibility, defines the patient population, and directly affects both enrollment feasibility and data validity. By analyzing an individual's genetic makeup, researchers can now identify specific genetic variations that influence disease susceptibility, treatment responses, and adverse reactions. Genetic testing reshapes clinical trials in three operationally significant ways: it determines which patients can even enter the eligibility pathway; it defines the stratification logic that underpins study design; and it generates data that affects both regulatory submissions and downstream recontact potential.
- Genetic testing allows researchers to select the most suitable candidates for a particular treatment and use more targeted participant groups within clinical trials, increasing the accuracy of results, reducing variability, and streamlining the drug development process.
- Genetic testing enables researchers to more deeply understand how DNA affects disease progression and treatment responses. By identifying genetic markers associated with specific diseases, researchers can develop targeted interventions that address the underlying causes, leading to more effective treatments and improved patient outcomes.
- Genetic testing allows for the identification of patient subgroups that may respond differently to a given treatment, allowing for more personalized medicines based on patients' genetic profiles. This not only optimises treatment success but also minimises unnecessary exposure to interventions that are unlikely to be effective for certain patients.
As genetically stratified programs scale across phases and geographies, the regulatory and operational requirements around testing will continue to shape how sponsors approach eligibility design, screening workflows, and multi-regional execution.
Regulatory requirements across the US, UK, and Europe
The regulatory landscape for genetic tests varies between the US, UK, and Europe due to different jurisdictions and regulations.
United States
In the US, the FDA oversees medical device safety and efficacy, including genetic tests. This regulatory system covers both Laboratory Developed Tests (LDTs) and In Vitro Diagnostic (IVD) Tests.
- LDTs: Laboratory developed tests are designed, manufactured, and used within a single laboratory. Historically, the FDA exercised enforcement discretion for many LDTs, even though diagnostic tests are generally regulated as medical devices under the Federal Food, Drug, and Cosmetic Act. Sponsors using LDTs in clinical trial screening or eligibility workflows should confirm the test’s current regulatory status and whether FDA review is required.
- IVD Tests: IVD tests must undergo a rigorous FDA review. Manufacturers need to demonstrate analytical and clinical validity as well as clinical utility to ensure the genetic variants identified are linked to diseases and improve patient outcomes.
The CMS, or Centers for Medicare & Medicaid Services, also regulates clinical laboratories, including laboratories conducting clinical genetic testing, using the guidelines of the Clinical Laboratory Improvement Amendments (CLIA).
In addition to device and laboratory regulation, sponsors should also account for US legislative requirements that shape how genetic information is collected, protected, and used in research:
- GINA — The Genetic Information Nondiscrimination Act protects against genetic discrimination in employment and health insurance, which can influence participant confidence during clinical trial recruitment. Notably, it does not extend to life, disability, or long-term care insurance, and it does not apply to employers with fewer than 15 employees.
- HIPAA — The Health Insurance Portability and Accountability Act governs genetic data as protected health information, creating compliance requirements for sponsors around data handling, storage, and disclosure.
United Kingdom
The UK has its own regulatory framework post-Brexit, overseen by the Medicines and Healthcare Products Regulatory Agency (MHRA). For genetic testing, the UKCA mark applies to in vitro diagnostic devices (IVDs) and indicates compliance with the UK's medical device regulations, including requirements related to safety, quality, and performance under MHRA oversight. This is important for genetic testing for research as well as direct-to-consumer genetic testing, as both need to meet certain requirements before they can be used by patients or consumers.
For sponsors running multi-country studies with UK sites, the evolving UKCA and CE marking transitional period can create practical differences in which testing kits or platforms can be supplied, what documentation is required, and how vendors are qualified across UK and EU geographies.
Europe
In Europe, the CE marking indicates conformity with European Union regulations for medical devices, including genetic tests. The In Vitro Diagnostic Regulation (IVDR) also aims to establish more consistent standards for IVD tests across member states. It requires device manufacturers to conduct clinical performance studies and provide evidence of safety and performance in line with a device’s assigned risk class.
The IVDR replaced the earlier IVDD and introduced a risk-based classification system that moved many genetic tests into higher risk categories, including some companion diagnostics and germline variant detection. Sponsors should verify that their genetic testing partners and laboratories meet current IVDR classification requirements for the tests being used in trial screening or eligibility workflows.
Balancing innovation and safety
Regulatory requirements for genetic testing are not a background consideration for clinical trials. They shape study design, influence site and vendor selection, affect testing logistics, and can change how sponsors approach participant engagement and consent.
Across jurisdictions, the compliance inputs differ. In the US, sponsors often need to account for FDA oversight, CLIA laboratory requirements, and legislative frameworks such as HIPAA and GINA. In the UK, MHRA oversight and UKCA marking define how IVD devices can be supplied and used. In Europe, the IVDR and CE marking requirements set expectations for evidence and performance based on risk classification.
This means testing workflows designed for one market may not transfer cleanly to another. Differences in device status, laboratory qualification, and documentation requirements can surface as operational friction if they are treated as late-stage compliance checks rather than design constraints.
For sponsors running multi-regional genetically stratified programs, building regulatory awareness into the earliest stages of study planning helps reduce downstream rework and supports more predictable execution.