Mind the Gap: aligning terminology and stakeholder expectations
Bringing a medical device to clinical trial is one of the most significant milestones in any development journey. Yet terms such as prototype, production‑ready, or clinical trial device are often used loosely, and inconsistently with potential for confusion between stakeholders about the maturity of a design and the level of rigour required before involving human participants.
At the heart of medical device regulatory requirements is a simple but essential principle – safety and efficacy must be demonstrated, and the benefits must outweigh the residual risks. That mindset should shape every technical, regulatory and design decision, long before a device reaches a clinical setting.
In this article, we explore what ‘clinical trial device’ really means, why consistent terminology is crucial to a shared understanding of the stage of development, and how this links to what regulators expect before approving a clinical investigation.
The Medical Device Mindset: Safety, Efficacy and Risk
Unlike many other product development sectors, the MedTech sector (specifically medical devices) is governed by strict regulations designed to protect patients and users. Whether operating under the EU MDR, UK MDR or FDA regulations, manufacturers must:
- minimise risk to patients and users
- prove the device does what it claims
- comply with relevant harmonised and designated standards
- demonstrate that any remaining risks are justified by the expected clinical benefits
Risk management is not a one-off task; and works alongside verification and validation testing – appropriate to the stage of development – as a continuous, iterative process carried out throughout the device’s lifecycle.
Why Terminology Matters
The adoption of an established description methodology, such as Technology Readiness Levels (TRLs), helps set a common context. To aid our clients, we created an online resource comprised of a TRL self-assessment and TRL framework, against which they can identify their current stage of development and build a long-term vision by measuring how ‘technically ready’ and ‘mature’ their device is.
However, while TRLs are useful as a tool for more formalised assessment, they don’t really reflect the day-to-day terminology used during product development, where terms like proof-of-principle, alpha prototype, beta prototype, design for manufacture, production intent and production ready are much more common; yet these can mean different things to different people and context can be equally important.
When discussing devices intended for clinical investigation, terminology misalignment can become problematic and a source of confusion. Referring to a device intended for use in a clinical investigation as a ‘clinical trial prototype’ can give the impression of immaturity or unreliability, which is the opposite of what regulators are looking for. Whereas a device that is described as ‘production‑ready’ has a manufacturing focus and implies that all design validation, verification and manufacturing process/cost optimisation has been completed, which is not necessarily the case at the clinical trial stage.
A device for clinical investigation needs to be representative of the intended final product, appropriately compliant with applicable standards and sufficiently stable, safe and reliable for use on human subjects. However, this is not the same as saying devices for clinical investigation must be identical to the final production design. In fact, certain trial‑specific modifications, such as enhanced data logging, are often required and may intentionally differ from later production units.
The MHRA guidance is available online Clinical investigations of medical devices – Compiling a submission to MHRA
Similar guidance is available from other European authorities, the FDA and other global regulators. As with most aspects of the medical device regulatory process, there are regional differences in requirements and the regulatory approach taken; however, there is also sufficient commonality that the basic principles outlined in the MHRA guidance provide a good foundation for medical device developers.
Understanding Pre Clinical Data: Research vs Clinical Evaluation
Before human trials begin, medical device developers should explore every practical avenue to de-risk their technology. This typically involves a combination of fundamental research to confirm the basic scientific principles, empirical performance characterisation using calibrated equipment, and laboratory testing with representative material or ex vivo tissue to understand how the device is likely to behave in real-world scenarios. Development teams may also use simulated approaches, such as in-silico modelling, to predict performance and where appropriate, may need to undertake animal studies to gather essential in-vivo data, prior to first-in-human studies.
At this point, a key distinction must be made between scientific research and the clinical evaluation data required for regulatory approval. Research data is generated to test scientific hypotheses and refine early concepts, whilst clinical evaluation data gathered during a formal clinical investigation is required to satisfy the regulatory expectations set out in the MDR.
The objectives and endpoint for a research study are different to the regulatory requirements for clinical evaluation. Organisations that are more familiar with basic scientific research can often underestimate how much additional work is needed to meet these regulatory standards, and proper planning of both is vital to avoid delays later in development. A clinical evaluation to demonstrate safety and efficacy is not about proving the science works. If that is the purpose of your next round of experiments, then the device is actually at an earlier stage of development, and the design of the research study and ethics approval process should be adjusted accordingly.
What Regulators Expect Before Approving a Clinical Investigation
Clinical investigations typically occur towards the end of the development cycle and act as the final confirmation of safety and efficacy. In the UK, the device must be approved by the MHRA and an ethics committee before first‑in‑human use. Similar principles apply across the EU and the FDA.
To secure approval, developers must submit a robust body of evidence demonstrating that the device is ready for clinical investigation. From a design and development perspective, applications must demonstrate:
1. Comprehensive device information
Regulators expect a complete and transparent description of the device, covering its intended purpose, overall design and method of operation. This typically includes detailed engineering drawings, block diagrams illustrating system architecture, and clear photographs of the clinical trial device. Where helpful, developers may also submit short videos that walk reviewers through the device’s assembly, user interface and operational steps. The goal is to help assessors understand exactly how the technology functions and whether any design features could pose risks during human use.
2. Standards compliance
A clinical investigation application must map the device against all relevant standards and regulatory requirements. For medical devices in Europe, this includes demonstrating alignment with the General Safety and Performance Requirements set out in MDR Annex I. Applicants should present a structured checklist showing which requirements have been addressed and how compliance has been verified in practice. This is usually supported by formal test reports, certificates or technical assessments that provide evidence of conformity with recognised standards.
3. Risk analysis
A thorough risk analysis performed in accordance with ISO 14971 is essential. This documentation should outline the full risk management process, covering hazard identification, risk estimation, and the measures taken to reduce risks to an acceptable level. Regulators also expect developers to consider additional hazards specific to multi-component or integrated systems, such as compatibility issues between different modules or accessories. If the device contains or interacts with medicinal substances, these associated risks must also be assessed and clearly justified.
4. Labelling and Instructions for Use
Regulators require draft labelling and Instructions for Use to ensure that investigators and participants will be properly informed during the trial. All mandatory warnings, operating instructions and safety notes must be clearly presented. Importantly, devices used in clinical investigations in the UK must carry the legally required statement “Exclusively for clinical investigations”, so that they are not mistaken for commercially approved products.
5. Bench and pre-clinical testing
Before any human exposure is considered, regulators expect a solid portfolio of bench and pre-clinical testing. This includes summaries of the methods used, the acceptance criteria applied, and the rationale behind the selection of test models or materials. Test results should show that the device consistently performs within safe and expected limits. If any animal studies, tissue studies or ex-vivo evaluations have been conducted, these must be included to demonstrate that the device has been appropriately assessed in more realistic biological environments before moving into a clinical setting.
6. Software documentation
For devices containing software or algorithms, regulators require comprehensive documentation demonstrating that the software has been developed, verified and validated using recognised processes. This usually includes development plans, risk and hazard analyses, verification and validation reports, and evidence of configuration management. The purpose is to ensure that the software is stable, predictable and unlikely to behave unexpectedly during human use.
Real World Examples: When the Clinical Trial Device Becomes the First Product
For many early‑stage companies, the devices built for clinical trials inevitably become the first units used in the market. This is not because the design is fully refined or ready for manufacture; far from it. It is simply a commercial necessity. Start-ups need to demonstrate traction early; to get real users interacting with the technology, to test market appetite, and to prove initial revenue streams long before the product is optimised for large‑scale manufacture.
These early devices may not yet reflect the cost, robustness or production efficiencies of a future commercial design. However, they are much more than prototypes. They still need to be clinical‑grade, fully compliant and reliable in real‑world use. After regulatory approval, by manufacturing in low volume and placing these ‘clinical trial devices’ directly into the hands of early adopters, companies can validate core assumptions, capture critical user insights and generate further evidence required to define, and fund, the next iteration of the product.
Start-ups and scale-ups generally accept, and often expect, that their launch product will evolve meaningfully before reaching a stable, higher-volume commercial version. With tight resources and intense pressure to prove market value quickly, they are willing to progress quickly from clinical trials with a device design that achieves regulatory compliance but may still require significant refinement before volume production. Early deployment becomes part of the commercial strategy, not just the regulatory pathway. By deploying these early devices, companies can validate their value proposition, refine their understanding of user needs and gather the evidence required to shape the next generation of the product.
Although these devices are not yet optimised for high volume manufacture, cost efficiency or long-term reliability, they are far more than simple ‘prototypes’. They must still meet clinical-grade expectations, comply with all relevant regulatory requirements and perform consistently in the field.
Different Organisations, Different Risk Appetite
Larger organisations may take a different approach. More established brands with defined manufacturing infrastructure and the ability to invest more heavily upfront, typically prefer to reach clinical trials with a design that is already close to final form. Their internal processes and higher expectations for design maturity naturally encourage a more conservative risk profile.
Final Thoughts
The term ‘device for clinical investigation’ carries specific technical and regulatory meaning. It is more than a prototype, but it is not yet an approved, fully production‑ready product. Instead, it refers to a device at a stage of development where it is demonstrably safe and effective for human use, complies with relevant standards, is representative of the intended production design and can reliably generate meaningful clinical evidence.
In a formal application for a clinical investigation, regulators expect devices used in clinical trials to be substantially compliant with applicable standards, with a clear evidence base for basic safety. Everything that can be tested and validated before human trials should be completed first. While this may mean that devices for clinical investigation are >90% of the production‑intent design, this is not the same as saying they are ‘full production devices’. Regulators are primarily concerned about the safety of trial participants, but they also recognise that trial devices may intentionally differ from production units where required by the study protocol.
Understanding these nuances within your organisation helps set realistic expectations, improves communication between stakeholders and ultimately supports more successful development programmes.
If you are navigating these complexities or preparing for a clinical investigation, eg technology can help guide you through each stage. Our team can support you in building clinical‑grade devices, aligning with regulatory expectations, and ensuring you generate the evidence you need to progress confidently.
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Contact us via email on design@egtechnology.co.uk, by giving us a call on +44 01223 813184, or by clicking here.
