What is biocompatibility?

Biocompatibility is a material’s ability to interact with the human body without causing harm. If the material in a medical device causes irritation, toxicity, or other adverse effects, it could pose serious risks to the patient. 

This is especially true for implants or devices that interact with blood, tissue, or internal organs. Anything that interfaces with the body needs to be biocompatible. Even seemingly simple devices, like plasters, contact lenses or wearable glucose monitors, require careful scrutiny.

The bar for biocompatibility is raised

Under the EU’s previous regulation, the Medical Devices Directive (MDD), manufacturers were often able to rely on legacy data or limited routine testing. However, the MDR raises the bar considerably:

• More clinical evidence is required
• Risk-based thinking is embedded in every step
• Material traceability must be maintained throughout the device’s lifecycle

In the past, a single test might have been enough. Now, manufacturers need to understand how every material is used, processed, cleaned, and sterilized, and how it might interact with the human body on an ongoing basis.

Seeking standards for biocompatibility?

Thankfully, you don’t need to start from scratch. The ISO 10993 family of standards offers a structured approach to biological evaluation. With 23 parts covering everything from genotoxicity to skin irritation and immunotoxicology, these standards help you identify relevant tests for specific devices. They include, among others:

• ISO 10993-1: Evaluation and testing within a risk management process
• ISO 10993-5: Tests for in vitro cytotoxicity
• ISO 10993-10: Tests for irritation and skin sensitization
• etc.

The challenge for manufacturers is knowing which tests are relevant to them, and how to interpret the results. Most commercial labs will return raw data, so it’s up to you as the manufacturer to translate that into meaningful conclusions. This is where regulatory expertise becomes essential.

Practical considerations for manufacturers

Biocompatibility requirements apply across all device risk classes, from Class I plasters to Class III implants. The depth of evidence required varies, but the principle is the same: prove your product is safe for its intended use and specified duration. For example, contact lenses may be safe for short-term wear but not extended use. Implants may need to demonstrate safety over many years. Testing often involves:

• in vitro studies
• clinical trials
• animal testing studies

Post-market surveillance is also an important, ongoing component of biocompatibility compliance. Manufacturers must monitor real-world use, respond to new research data, and adapt if evidence around material safety evolves, even years after a device is on the market.

Biocompatibility in the real world

In practice, proving biocompatibility can get technically and logistically complex. For instance, imagine you produce tubing for circulating blood around the human body. You would need to test it for chemical ‘leachables’ in worst-case scenarios, mimicking real-life use cases.

This example would necessitate a setup where blood is pumped through the tubing for extended periods of time. Lab analysis would then reveal if anything was released into the blood, and whether it was within safe thresholds. This kind of real-world testing is critical for market entry. Not only does it demonstrate biocompatibility, but it also provides peace of mind for clinicians and patients alike.

The emerging role of AI

An exciting development in this space is the emergence of AI and computer modelling to support biocompatibility evaluations. While not yet a replacement for traditional testing, AI has the potential to predict how materials interact with biological systems. 

These sophisticated computer models are improving all the time. In the not-so-distant future, they could help reduce our reliance on animal testing and accelerate biocompatibility approval. But for now, they’re a supplement, not a substitute for rigorous scientific testing.

How we can help

Here at Peercode Regulatory Consultancy, we support medical device manufacturers throughout their biocompatibility journey. That includes:

• Assessing gaps in your technical dossier
• Defining your biocompatibility testing strategy
• Supporting ISO 10993 test selection
• Performing literature reviews for material qualification
• Interpreting raw lab data
• Supporting clinical evaluations
• Training your team on relevant ISO standards
• Assisting with audits 
• Notified Body selection and communication
• Setting up post-market surveillance processes

In most cases, biocompatibility is just one component of a broader package of regulatory support, from initial design through to fully MDR-compliant technical documentation.

Patient safety is always our number one

Patient safety is the heart and soul of the MDR. Every test, every document, and every process adds up to ensuring that your device is safe to use. If your device interacts with the human body in any way, biocompatibility can’t be an afterthought. It’s a foundational requirement, and one that demands technical rigor, strategic planning, and expert interpretation.

Need help navigating regulatory compliance for your medical device? Let’s talk!