When Is a Medical Device Really ‘Inventive’?

The Role of Patents in MedTech

Medical device innovation is often a result of small improvements rather than dramatic breakthroughs. This can be attributed to regulatory constraints, clinical safety and risk management which drive refinement over reinvention. Nonetheless, these small changes can be just as, if not more, commercially valuable compared to large advances and thus it is important that these small changes are protected. 

Intellectual property (IP) rights play an integral role in protecting innovation in the medical device industry. The most common form of IP right used to protect medical devices is patents, which protect inventions. In patent law, an invention generally refers to a technical solution to a technical problem. In the medical device context, this can include the medical device itself, a specific component or sub-system of the device, a method or process for manufacturing the device, or a method of operation or use. 

Patent rights grant the patent holder the right to exclude others from, for example, making, using, or selling the invention for typically up to 20 years, in return for publicly disclosing the invention. In order to justify such a ‘monopoly’ right, the invention must satisfy core patentability requirements, which include: 

1. Novelty (your invention must be new – if it has already been made publicly available anywhere in the world, patent protection is not available), 
2.  Inventive step (your invention is not obvious – the invention must go beyond what someone with knowledge and experience in the relevant field would consider an obvious modification to existing technology), and 
3.  Industrial applicability (your invention must be something that can be made and used in any kind of industry). 

What is the Inventive Step Requirement?

Inventive step is an important, and often the least understood, patentability requirement. Its purpose is to prevent protection for routine or logical developments which do not utilise innovation or creativity. 

In the case of medical devices, the requirement of inventive step asks whether a medical device goes beyond an ‘obvious’ modification of existing technology or knowledge. It may be the case that a solution is not obvious, for example, because the prior knowledge or technology points away from it, known alternatives introduce unacceptable trade-offs, or regulatory constraints make certain design routes impractical. 

While it is often easiest to recognise inventive step in ground breaking innovation, it is important to note that small but meaningful improvements are also protected when they solve a technical problem in a non-obvious way. 

Below a real-world example of ‘incremental’ innovation in medical devices is used as a case study to explore how incremental innovations can be framed to meet the patentability requirement of inventive step. 

Patent Protecting Incremental Innovation in Medical Devices – Case Studies

Drug-Eluting Stents 

Drug-eluting stents (DES) are tiny metal mesh tubes coated with medication used in coronary angioplasty to keep narrowed heart arteries open, thus preventing restenosis (re-narrowing). By slowly releasing drugs to inhibit tissue growth, DES reduce the need for repeat procedures compared to bare-metal stents. DES have thus revolutionised the treatment of coronary artery disease. DES have evolved from thick-strut, permanent-polymer stainless steel devices to thinner-strut cobalt-chromium platforms with biocompatible/bioabsorbable polymers through small and frequent advances. There are over 20 different DES types for cardiologists to choose form, each with unique features and characteristics (Nicolas et al. 2023). 

Boston Scientific Corporation (BSC) is an American biotechnology and biomedical engineering firm that manufactures a broad range of medical devices for numerous medical fields, including cardiac surgery. The company is known for the development of the Taxus® DES, which was approved for use in Europe in 2003 and for use in the United States in 2004. BSC has a vast patent portfolio related to stents; their earliest stent-related patent application was filed for in 1997. Some of their patents demonstrate how their stents have evolved through small adjustments and changes.  

For example, BSC filed 19 patent applications across 2013 to 2015 that all specifically relate to anti-migration coatings for stents, with each patent right protecting a subtle but distinct difference. To highlight a select few, WO2013152338 sought broad protection of an anti-migration stent coating, while WO2014065941 sought to specifically protect a tacky anti-migration stent coating, WO2014042875 sought to protect an bioadhesive anti-migration stent coating, and WO2015020676 sought to specifically protect a biodissolvable anti-migration stent coating. Similarly, WO2014143750  introduced an anti-migration stent coating comprising protrusions at the base of the stent, and WO2014143730 followed up with an anti-migration stent coating comprising two sets of protrusions which point in opposing directions. 

The refinements encompassed in the above patent applications are directed to addressing the technical problem of stent migration, and the claimed features are framed as providing improved anti-migration performance. Such incremental innovations have the potential to be commercially valuable to BSC.  

Below are images of a DES with an adhesive coating, taken from BSC’s patent WO2014042875. 

What is notable in this example is the deliberate accumulation of narrowly focused patent rights covering multiple variations on a common technical theme. Each application captures a discrete design choice, collectively creating a dense IP landscape around anti-migration performance. This approach makes it significantly harder for competitors to implement similar solutions without encountering infringement risk.

Commercial Value

Patents aren’t just for “disruptive, ground-breaking” inventions. In the medical device field, competitive advantage is often built on incremental innovation and these refinements can be just as important to protect. 

From a commercial perspective, failing to identify and protect incremental improvements with patents can have tangible consequences. Unprotected innovations can be easily copied, meaning competitors can catch up quickly, undercut prices, and take market share. Furthermore, a weak or fragmented patent portfolio can reduce company valuation, complicate fundraising endeavours and weaken negotiating positions in partnerships or acquisitions. Conversely, a well-constructed patent portfolio around incremental improvements can create a meaningful competitive moat, deter competitors and support long-term value creation. 

In practice, medical device innovators can strengthen their position by:

• clearly articulating the technical problem each refinement addresses,
• documenting why the solution was not obvious at the time of development,
• connecting technical advantages to regulatory, clinical or manufacturing benefits, and
• considering patent protection early, before public disclosure or product launch. 

Recognising the commercial value of small improvements and protecting them can be the difference between leading a market and following it.

References

• Nicolas J, Pivato CA, Chiarito M, Beerkens F, Cao D, Mehran R. Evolution of drug-eluting coronary stents: a back-and-forth journey from the bench to bedside. Cardiovasc Res. 2023 May 2;119(3):631-646. doi: 10.1093/cvr/cvac105. PMID: 35788828. (https://pubmed.ncbi.nlm.nih.gov/35788828/)
• https://www.bostonscientific.com
• https://www.bostonscientific.com/en-US/products/stents–coronary/taxus-express.html
• https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2013152338&_cid=P12-ML6LWU-82160-11
• https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2014065941&_cid=P12-ML6LWU-82160-11
• https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2014042875&_cid=P12-ML6J0U-91902-1
• https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2015020676&_cid=P12-ML6JHS-07127-1
• https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2014143750&_cid=P12-ML6N3I-26001-16
• https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2014143730&_cid=P12-ML6N3I-26001-16
• Yang XL, Liu GZ, Tong YH, Yan H, Xu Z, Chen Q, Liu X, Zhang HH, Wang HB, Tan SH. The history, hotspots, and trends of electrocardiogram. J Geriatr Cardiol. 2015 Jul;12(4):448-56. doi: 10.11909/j.issn.1671-5411.2015.04.018. PMID: 26345622; PMCID: PMC4554791. (https://pmc.ncbi.nlm.nih.gov/articles/PMC4554791/)
• https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2014107700&_cid=P12-ML6QW7-41915-1

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