4 wearable medical device challenges solvable at the design stage
Dave Liebl, Intricon, discusses how strategic decisions made early can reduce costs, accelerate time to market, and foster commercial success.
Medical biosensors represent opportunities for innovative companies to disrupt and lead a market destined for exponential growth – from $28.5 billion in 2022 to $58 billion by 2032. Wearable medical devices, in particular, are an exciting frontier for startups and OEMs, but there are significant obstacles to the commercial viability of any device:
The FDA denies approximately 25% of medical devices annually.
Approval doesn’t guarantee success; many devices never make it to market.
Recalls can doom those that do. Medical device recalls increased by 8.8% in 2022 vs. 2021, totalling 911 recalls affecting more than 438 million devices.
There’s a lot at stake when companies invest anywhere from $200,000 to $41 million over two to 132 months to earn 510(k) clearance – and even more for De Novo classification.
These circumstances underscore the need to take an approach to medical biosensor development that accounts for manufacturing, quality, and cost controls – early in the design process -- to not only meet regulatory requirements but also enter the market with a commercially viable product. Consider these four key wearable medical device challenges and solutions.
1. Material selection
Plastics are excellent, low-cost alternatives to metals and other cost-prohibitive materials that can preclude a device from achieving success. Still, many designers aren’t aware of the latest advances in polymer science for wearable biosensors, so they often make the mistake of relying only on materials they’re familiar with. That may make sense, since qualifying a new material is expensive. However, it also limits possibilities.
For example, it can be easy to overlook how a given chassis material might interact with patients, such as when oils on the skin may react with some plastics and render devices unwearable.
Structural integrity is also critical. On one project, a medical device designer consulted Intricon for an alternative to polycarbonate as it wasn’t strong enough for the intended application. Intricon’s engineers identified a better, low-cost material that offered superb strength.
The device met structural integrity requirements and was easy to sterilise because the material could withstand gamma radiation. If the designers hadn’t consulted the manufacturer early in the process, they might have produced an inferior, costlier device that might not have been adopted or profitable.
2. Cost and commercial viability
Designers often wait to consult manufacturers until they’re ready for production quotes. At that advanced project stage, manufacturers are constrained by the design concept. They must find a way to manufacture the device to specifications, but those specs might not be the most efficient or cost-effective. Changes are limited only to those required for production feasibility, not those that could enhance the product or manufacturing process.
If manufacturers are consulted earlier in the process, they can recommend adjustments that minimise late-stage changes, significantly reduce costs, and accelerate time to market.
The need to scale production volumes influences cost and commercial viability. You must be able to design and manufacture a product that will hit cost targets at scale. Whether you design ten, 100, or 1,000 workable parts, success lies in your ability to sell it profitably at scale at prices the market will accept.
Patient and clinician acceptance is also key to commercial viability. From the patient perspective, consider how the wearable device interacts with the user. How long will it be in contact with the patient? Will it be comfortable? Clinicians must also have confidence that the device will perform and deliver a positive patient experience. Keep end-user needs and interactions in mind when making design decisions and material choices.
3. Manufacturability
Designers sometimes overlook the value of consulting with manufacturing experts, but working with a proven and trusted manufacturer from start to finish is best practice. Create a concept and then consult a manufacturer to complete a Design for Manufacturing (DFM) review. Lean on manufacturers and stay open to suggestions and modifications. Proven manufacturers know the best way to efficiently and cost-effectively execute the design vision. Remember that there is always more than one way to make a product.
For example, when invited to be involved from design kickoff, Intricon has reduced design timelines by many weeks and accelerated time to market by many months by making design suggestions and addressing manufacturing concerns as the design evolved.
With medical wearables, a manufacturing expert can help designers understand limitations and opportunities, especially as demand increases to make components smaller without sacrificing structural integrity and functionality. For example, connectivity is crucial for many medical biosensor devices, so designers often want to encapsulate antennas, magnets, and other components in plastic. However, that isn't easy to do without affecting functional integrity. Plastic moulding involves high temperatures and pressures that shift components around and reduce the functionality of magnets in electronics.
There are better ways to encapsulate an assembly, but designers aren't always aware of the manufacturing options. Overmoulding is a good example. Think of an Easter egg with two halves: you can put anything inside, and the egg will protect it. With overmoulding, a base component (called a substrate) is moulded and allowed to cure. Then, a second layer is moulded directly on top to create a single, solid piece with a hermetic seal. WiFi antennas, Bluetooth mechanisms, magnets, and other components can be put inside the "egg" without exposure to high pressures or temperatures. Everything stays protected, uniform, and in place.
4. Clinical and regulatory requirements
The global biosensor market is constrained by existing and evolving regulations, complicated reimbursement policies, and slow adjustments to new technologies. A National Institutes of Health time-to-market analysis found that the main bottleneck is the clinical trial stage, where failures are rooted in insufficient design, poor understanding of user requirements, and lack of testing early in the development process.
Consider how the product will meet clinical and regulatory requirements early in the design stage. Many companies go too far too fast, only to find they’ve missed critical steps that end up delaying time to market and inflating costs at later stages.
Knowing the device’s classification and researching regulatory guidance and precedents is vital. However, that can prove challenging when real-life requirements often extend beyond documented rules and include the experience of precedents and related submissions. An experienced partner can help develop the regulatory strategy and craft the submission to earn FDA approval. It might seem like an extra step, but it’s far more cost effective to solve potential issues during the design stage than to re-engineer after FDA denial.
With demand for medical biosensors at an all-time high, the opportunity for new wearable devices is upon us. For medical device companies seeking to bring biosensors to market, consider consulting with experts who can help make critical decisions at key points to minimise challenges and vastly increase the chances of commercial success.