FDA Biocompatibility Expectations Are Evolving: What ISO 10993-1:2025 Means for Medical Device Manufacturers
Biocompatibility has long been a critical part of medical device development and FDA submissions. But FDA continues to move away from treating biological safety as a simple checklist of tests and toward a more comprehensive, risk-based evaluation of the finished device.
That shift is becoming even more important with the introduction of ISO 10993-1:2025.
On September 9, 2026, FDA held the first in a series of Town Halls addressing recent updates to ISO 10993-1:2025 and approaches for evaluating medical device biocompatibility. The session focused on risk assessment, including examples involving material-mediated pyrogenicity and systemic endpoints. Additional FDA Town Halls are scheduled for September 23 and October 7, covering chemical characterization and toxicological risk assessment.
FDA Has Partially Recognized ISO 10993-1:2025
FDA recognized the sixth edition of ISO 10993-1:2025 on May 25, 2026, under Recognition Number 2-313.
Importantly, however, FDA granted partial recognition, not complete recognition.
This distinction matters.
Manufacturers should not assume that simply following every provision of ISO 10993-1:2025 will automatically satisfy FDA expectations. FDA specifically excluded certain provisions from its recognition, meaning that U.S. submissions still need to be evaluated within FDA's own regulatory framework and applicable guidance.
In practical terms, a blanket statement such as:
“The device complies with ISO 10993-1:2025.”
may not, by itself, be sufficient to support an FDA submission.
Manufacturers need to demonstrate how their biological evaluation strategy appropriately addresses the risks associated with the actual finished device.
Start With the Device — Not the Test Menu
One of the most important principles reinforced by FDA's current approach is that biocompatibility evaluation should begin with understanding the device itself.
Instead of starting with:
“Which ISO 10993 tests do we need?”
manufacturers should first evaluate factors such as:
the type and duration of patient contact;
the materials and chemical constituents of the device;
manufacturing and processing methods;
sterilization and cleaning processes;
previous use or safety history of the same or similar materials;
applicable biological endpoints;
available chemical characterization or toxicological data; and
whether existing information already adequately addresses the identified biological risks.
Only after these factors are understood should manufacturers determine whether additional testing is actually necessary.
This is consistent with FDA's stated goal of evaluating biocompatibility using a risk-based and least-burdensome approach.
“We Completed ISO 10993 Testing” May Not Be Enough
A common misunderstanding is that completing a standard panel of ISO 10993 tests automatically establishes biocompatibility.
FDA's approach is broader than that.
The key question is not simply whether testing was performed, but whether the overall biological evaluation adequately addresses the risks presented by the finished device.
For example, FDA may consider whether:
the test article truly represents the final marketed device;
manufacturing or sterilization could introduce new chemical constituents or residues;
the selected endpoints are appropriate for the intended contact type and duration;
existing data are sufficiently relevant to the proposed device; and
the rationale for omitting certain tests is scientifically justified.
A device may therefore have several completed biocompatibility test reports and still receive FDA questions if the underlying biological evaluation strategy is incomplete.
Existing Evidence May Reduce the Need for Additional Testing
A risk-based approach does not necessarily mean more testing.
In some cases, the opposite may be true.
Existing information may help support biological safety without repeating testing unnecessarily. Depending on the device, relevant evidence could include:
prior testing on the same material or device configuration;
established clinical or commercial history;
chemical characterization data;
toxicological assessments;
supplier material information;
scientific literature; or
data from a legally marketed device with appropriate comparability.
The important point is that manufacturers need to explain why that evidence is relevant and sufficient.
Biocompatibility should therefore be viewed as an evidence-based biological safety assessment, rather than simply a list of laboratory studies.
When Should Manufacturers Consider FDA Feedback Before Testing?
For relatively straightforward devices, manufacturers may be able to establish an appropriate biological evaluation strategy using FDA guidance and recognized standards.
However, early FDA feedback may be beneficial for more complicated situations, including devices involving:
prolonged or permanent body contact;
novel materials;
new manufacturing processes;
complex chemical exposures;
unusual degradation products;
significant changes to an existing device; or
uncertainty regarding the appropriate biological endpoints.
In these situations, manufacturers may consider discussing the proposed approach with the relevant FDA review office, including through the Q-Submission process where appropriate.
Resolving these questions before testing begins can help prevent unnecessary studies and reduce the risk of major information requests later in the review process.
What About the Previous ISO 10993-1 Standard?
Manufacturers do not need to transition immediately.
FDA continues to provide a transition period for the previous version of ISO 10993-1, allowing manufacturers time to adjust ongoing development and submission programs.
This means companies with existing testing strategies should not automatically assume that all prior testing must be repeated solely because a new edition of the standard has been issued.
Instead, manufacturers should assess whether their existing biological evaluation remains scientifically and regulatorily appropriate for the proposed device and submission.
FDA Is Increasing Its Focus on Biocompatibility Resources
FDA also updated several biocompatibility resources on September 9, 2026, including its Biocompatibility Assessment Resource Center, glossary, and guidance on what information should be included in a test report.
This is another indication that FDA is placing increasing emphasis not only on the tests themselves, but also on the quality of the supporting rationale and documentation.
For manufacturers, strong documentation should clearly explain:
what biological risks were identified;
what evidence was reviewed;
why particular endpoints were or were not evaluated;
how the test article represents the finished device; and
why the overall evidence supports biological safety.
What Medical Device Manufacturers Should Do Now
If your company is preparing a 510(k), De Novo, PMA, or another FDA submission, this is a good time to review your biocompatibility strategy.
Before initiating testing, manufacturers should ask:
1. Have we correctly defined the device's body-contact category and duration?
2. Do we fully understand the materials and manufacturing processes associated with the finished device?
3. What biological endpoints are actually relevant?
4. What existing evidence can already support the evaluation?
5. Are additional laboratory studies truly necessary?
6. Does our documentation clearly explain the scientific rationale behind the strategy?
7. Would early FDA feedback reduce uncertainty before we begin testing?
Addressing these questions early can significantly reduce unnecessary testing, development costs, and avoidable FDA questions.
Final Takeaway
The introduction of ISO 10993-1:2025 reinforces an important trend in FDA medical device regulation:
Biocompatibility is not simply about completing a standard series of tests. It is about demonstrating that the biological risks of the finished medical device have been appropriately evaluated and controlled.
Manufacturers should therefore build their biocompatibility strategy around the actual device, its materials, manufacturing process, patient contact, and available scientific evidence.
Starting with the right regulatory strategy can help avoid unnecessary testing and reduce potential delays during FDA review.
At Provision Consulting Group, we support medical device manufacturers with FDA regulatory strategy, 510(k) and other premarket submissions, device registration and listing, U.S. Agent services, and ongoing FDA compliance support.
For companies preparing to enter the U.S. medical device market, early review of the biocompatibility strategy can help identify regulatory gaps before testing begins.
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