The Design Process of Medical Devices at DeviceLab | Part 4

Part 4: The 6 Development Tracks – Design in Parallel

Medical device development is an interdisciplinary task. Designers, engineers, scientists, manufacturing, regulatory, medical, legal, and business specialists all work together toward a common goal but have distinct contributions to medical device development. At DeviceLab, we’ve organized these efforts into six tracks, which cover the needs of most projects. Our RoadMap below shows this structure graphically.

Medical Product Design Roadmap DeviceLab

The Intellectual Property Track

This track begins with patent disclosures and searches and continues through a Freedom to Operate and Patentability analysis. As the product design evolves, provisional patent applications are prepared and alternative embodiments, such as “methods of making” and “picket fence” ideas are explored. One the design is mature, but before public disclosure, key design and method patents are filed. After this basis is established, an international IP strategy is implemented, and any available licensing options are explored.

While much of this work is done by lawyers, the development team contributes many of the ideas, depictions, data, and technical arguments. There is often some patent coverage extent before the start of a project, but valuable additional art is usually acquired during product realization, especially alternative embodiments and discovery of key design parameters.

The Medical Product Development Track

Product Development begins with Research and Conceptual Design. Building on this concept and User Needs, regulatory requirements, predicates, and known hazards, designers and engineers craft Design Input Requirements that capture the essential features of the intended product. Working from these inputs, the team creates and tests multiple iterations of the product design until all requirements appear to be met, and records the resultant design as Design Outputs. When Outputs are complete, they are compared against the Design Inputs in Design Verification, and the medical device itself is compared against the User Needs in Design Validation. Design Transfer follows, to ensure that the design is correctly transferred to manufacturing (Device Master Record) and all requirements will continue to be met. Throughout the process, a Design History File is accumulated.

 

Product Development is often done by specialist engineers and designers, rather than the inventor or technical team of the manufacturer. Along the way, multiple prototypes are created and tested, and design reviews are executed to ensure that the project is meeting its goals. 

The Risk Management Track

Risk Management starts with an investigation of similar products and known hazards, and as a design concept emerges, consideration of safety characteristics. In combination with User Needs, Intended Use, foreseeable misuses, and regulatory requirements, a Use Hazards Analysis is performed so that mitigation means can be incorporated into the design. Once detailed design features are established, Risk Analysis using tools such as FTA, FMECA, etc. are applied. Hazards are mitigated as far as possible and verified in the Risk Management Report. During Pilot Production, a process FMEA is performed, and residual and overall risks are assessed to ensure acceptability. Before transfer to manufacturing, a HACCP analysis is performed and a control plan is implemented. Depending on the device, Post-Market Surveillance systems may be established.

Depending on the size of the organization, the team players on the Risk Management Track may be specialists or the same people performing the design, human factors, manufacturing, or regulatory tracks. Many companies rely on consultants for tasks such as predicate and known hazard research.

The Manufacturing Track

The Manufacturing Track starts with a plan to manufacture, assemble, test, and package the device. If necessary, manufacturing processes are developed and demonstrated as a part of Proof-of-Concept. Vendors are selected and qualified in the Alpha Phase, and tooling and work instruction development follows in Beta. Operator training and process validation are completed as the first part of Pilot Production, where units needed for validation testing, marketing, or other purposes are produced. The Design Transfer Design Review marks the transition to production for sale.

 

As with Risk Management, manufacturing specialists (with a contract manufacturer, for example) can perform the tasks on this track, but they are often performed by development engineers due to their familiarity with the design.

The Human Factors Track

30% of medical device adverse incidents reported to the FDA are user errors, not device failures. Human Factors Engineering is applied to mitigate these risks by creating intuitive, comfortable, and fault-tolerant designs with proper instructions and/or training. The process begins with a consideration of user needs, combining information from literature, the MAUDE reporting system, and user research. During Design Input, the device interfaces, intended uses, and foreseeable misuses are considered. During Design Output, interface approaches are prototyped and tested to assure that they address Human Factors properly. Approaching Design Freeze, protocols are developed for Human Factors User Studies; generally, a Formative Study followed by a Summary Study. 

Most Human Factors/Usability engineering is typically performed by Industrial Designers working with the engineers doing the detailed mechanical, electrical, system, and software engineering. 

The Regulatory Track

The Regulatory typically begins with a consideration of predicate devices. Even for entirely novel devices, there may be predicates for major components or functions to be found in earlier devices. Based on this review, a strategy can be formulated for regulatory approval in the markets targeted. Beginning with an evaluation of the likely Classification (I, II, or III) of the device, and requirements coming from consensus standards covering the device type (e.g., IOL, heart monitor, scalpel) pertinent regulations can be applied. A plan for regulatory compliance is incorporated into the Design Plan. During Design Input and Output, a Design History File is maintained, and Design Reviews are performed to document compliance. During Design Verification and Validation, protocols are populated with any tests required by regulation or standard, and test outcomes are compared with requirements. Around the time of Design Transfer, the Regulatory Track is usually consumed with the production and presentation of a Design History File and Device Master Record in an approval process before FDA and/or an ISO Notified Body.

Regulatory Track tasks are usually performed by specialists. At larger companies, these people are usually in-house, but it is typical for startups and common for small companies to hire regulatory consultants to help out.

Conclusion

We hope this look into how the various disciplines operating in project work and cooperate stimulates your thinking about how to accomplish project goals in device development. Our next post in this series talks about how the Agile approach can be applied to the development of hardware as well as software, and what benefits this approach provides to the client. See the Process and Compliance pages on our website to learn more about how we do things.