Hi Anon,
I suggest you refer to ISO 10993-1:2018 whenever biocompatibility
testing is being considered. The title of the standards is "Biological
evaluation of medical devices - Evaluating and testing within a risk management process". I underlined the words testing and evaluation for emphasis. Testing is only one part of an evaluation (see section 4 of the standard for general principles of evaluation) . A biocompatibility evaluation looks at all factors that could affect a claim of biocompatibility, including existing information known about the material (publications), type tissue contact, duration of contact, repeated contact, risk of harm (anything from minor irritation all the way to poisoning and death), whereas biocompatibility testing per Table A of the standard is just one part of the overall evaluation.
You did not include information regarding duration of contact but you did state the tissue is skin. You also stated there is some known information about the material being biocompatible at other time points. You also know what the chemistry of the adhesive is, probably know what other products have used it, your risk assessment files should state possible harms, etc. It sounds like you may have enough data readily available to perform the risk-based assessment described in the standard. If you determine via this assessment that no further testing is required, this documented evaluation becomes your evidence for claiming biocompatibility.
FDA recognizes ISO 10993-1:2018 with an exception to Table A.1, which does not affect the evaluation portion of the standard, only the suggested battery of testing.
Good luck!
Sara
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Sara Coon
Associate Director, Regulatory Affairs
MN United States
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Original Message:
Sent: 24-Jun-2019 15:00
From: Anonymous Member
Subject: Retesting Biocompatibility?
This message was posted by a user wishing to remain anonymous
A medical device uses an accessory that has adhesive that touches the patient skin. The chemical components are inert. It has had biocompatibility testing completed without any concerns or issues. The accessory has undergone age testing to extend the expiration date. Again, no issues have been found and there have been no complaints received. However, an engineer in the company has expressed an interest in retesting biocompatibility, but with no apparent rationale. What should be done concerning biocompatibility testing for extended shelf life testing?