Overview
ISO/TS 37137-1:2021 - "Biological evaluation of absorbable medical devices - Part 1: General requirements" provides guidance for performing biological risk assessments of absorbable medical devices within the ISO 10993 framework. The technical specification clarifies key terms such as absorb, degrade, degradation product, and leachable (see Annex A) and sets expectations for identification, characterization and testing of materials and their degradation products throughout the device lifecycle.
Key topics and requirements
- Integration with ISO 10993-1: Biological evaluation of absorbable devices must follow ISO 10993-1 and related parts; any departure from standard methods needs written justification in the biological risk assessment.
- Terminology and scope: Clear definitions for absorb/degrade/degradation products and leachables to ensure consistent assessment and reporting.
- Degradation product characterization: Identify chemical identity, quantity, toxicity and particulate presence for substances released during manufacturing, shelf-life or in vivo degradation.
- Test article and sample considerations: Use final product (as‑marketed, including packaging and sterilization) where possible; sample preparation must preserve particulates unless welfare or technical considerations require otherwise.
- Extraction and in vitro testing: Recognize that standard extraction conditions were developed for non-degradable materials-absorbable devices may require testing at multiple degradation stages and potentially adjusted extract conditions (dilution, pH, osmolality). Any extract adjustment must be justified and documented, with appropriate controls.
- Interpretation of in vitro results: Account for how degradation products can alter test systems (e.g., pH/osmolality changes) and consider follow-up testing or alternate approaches as part of the risk assessment.
- Special considerations: Sterilization effects, drug–device combination products, particulates handling, and the influence of processing/format on biocompatibility.
Applications and who uses this standard
- Medical device manufacturers developing absorbable implants (polymers, ceramics, metals) - for preclinical testing strategy, material selection and design controls.
- Regulatory and quality teams preparing biological risk assessments and regulatory submissions.
- Biocompatibility scientists and testing laboratories designing test matrices, extraction protocols and interpreting results.
- Notified bodies and regulators evaluating safety dossiers and conformity with biological evaluation expectations.
Practical applications include planning degradation-product analyses, defining in vitro/in vivo test timing, documenting justifications for non-standard methods, and supporting claims of safety in regulatory submissions.
Related standards
ISO/TS 37137-1 is intended to be used with the ISO 10993 series, including (but not limited to):
- ISO 10993-1, -3, -4, -5, -6, -7, -9, -10, -11, -12, -13, -14, -15, -16, -17, -18 and ISO/TS 10993-19, -20, plus ISO/TR 10993-22.
Keywords: ISO/TS 37137-1:2021, absorbable medical devices, biological evaluation, degradation products, leachables, ISO 10993, biocompatibility, extraction, sterilization, device risk assessment.