Biocompatibility and Sterilisation Evidence for Class II and Class III Devices

1. Key takeaways

For Class II and Class III devices, Mexico approaches biocompatibility and sterilisation evidence through a summary plus standard citation format: biocompatibility is presented as a summary organised around the ISO 10993 series, and sterilisation is presented as a validation summary organised around the chosen method, together with the reasoning on packaging and shelf life. The simplified pathway can waive the underlying raw data, but it cannot waive the summaries; sterile devices are excluded from the low-risk exemptions altogether, and the depth of evidence progresses with the device class. Planning the evidence package around this layered structure, rather than around a single uniform list, is what keeps a Class II or Class III dossier complete without over-producing documents that the review does not request.

• Biocompatibility evidence follows the ISO 10993 series and is submitted in summary form.
• Sterilisation evidence covers the method, the validation, and the packaging and shelf life reasoning.
• The simplified pathway waives raw data but not the summaries.
• Sterile devices do not qualify for the low-risk exemptions of the 2025 protocol.

2. Legal basis

Four sources define the evidence framework. The baseline dossier requirements come from items I and VII of Article 179 of the RIS, as amended by the order published on 24 April 2026, which require scientific and technical information demonstrating safety and efficacy and laboratory testing that verifies the product specifications. The system-level requirements come from NOM-241-SSA1-2025, published on 4 April 2025, covering validation and verification and stability studies. The exclusion of sterile devices from the low-risk exemptions comes from the 2025 low-risk protocol, published on 15 July 2025. Finally, the symbols that may appear on labelling come from NOM-137-SSA1-2025, published on 19 May 2026, whose Appendix A contains 70 symbols, including symbols related to sterilisation methods. The table below consolidates these sources.

3. Expert insights

Insight 1: item VII of Article 179 asks for laboratory testing that verifies specifications. The provision positions testing as the verification of product specifications, which complements the systematic evidence of biocompatibility and sterilisation validation. In the dossier, the specification conformity testing and the biological and sterilisation evaluations should be presented as separate chapters rather than merged into one technical section. Keeping them separate mirrors the logic of the regulation, lets the reviewer locate each element against its own source, and avoids the impression that a specification test report is being offered in place of a biological evaluation, or the reverse.

Insight 2: sterility is the dividing line for depth of evidence. Sterile devices do not qualify for any of the low-risk exemptions under the 2025 protocol, and the sterilisation method, the sterilisation validation, and the reasoning on packaging and shelf life all belong in the dossier. The evidence burden for non-sterile Class I consumables is considerably lighter. This dividing line should be established at project start, because it determines not only which documents are prepared but which test laboratories and validation schedules must be booked, and those bookings have the longest lead times of the whole programme.

Insight 3: the simplified pathway waives the raw data, not the conclusions. The simplified pathway may waive the raw biocompatibility test data and the detailed design documentation, but the risk analysis summary and the conformity assessment summary remain on the submission list. Understanding the simplified pathway as a general exemption from documentation will leave the dossier incomplete. The correct mental model is that the conclusions travel, while the data behind them stay with the manufacturer and are retained for inspection when the authority asks.

Insight 4: the validation requirements of NOM-241-SSA1-2025 are more detailed. The 2025 edition makes explicit cross-references to other regulatory documents in two places, validation and verification, and stability studies, and it clarifies which product types the stability studies apply to. A quality system documented against the 2021 edition should be reviewed against these cross-references, since the added specificity can move obligations that previously lived in general procedures into defined, auditable records with their own acceptance criteria.

Insight 5: the sterilisation symbols on the label need a version change. Appendix A of NOM-137-SSA1-2025 incorporates 70 standardised symbols, including symbols related to the sterilisation method, covering ethylene oxide, radiation, steam or dry heat, vapourised hydrogen peroxide and others. Once the new standard takes effect, the sterilisation identification on labelling must be rearranged according to the new symbol system. Label artwork owners should treat this as a controlled change with its own verification step, because a symbol that is present but non-standard is a finding just as a missing symbol is.

4. Practical recommendations

• Structure the dossier in three chapters: specification conformity testing, biological evaluation summary, and sterilisation and shelf life.
• Present the biological evaluation as a summary organised around the ISO 10993 series, noting the type and duration of contact.
• State the sterilisation method, the validation standard and the packaging validation conclusion in the sterilisation chapter, and give the basis of the shelf life reasoning.
• For simplified pathway applications, retain the summaries while keeping the raw data on file for inspection.
• Schedule the label symbol version change around the entry into force of NOM-137-SSA1-2025, which is 360 calendar days after publication.

5. Verification checklist

• □ The three-chapter dossier structure is in place (specifications, biology, sterilisation and shelf life).
• □ The biological evaluation is presented as a summary organised around the ISO 10993 series.
• □ The sterilisation method and validation conclusions are stated.
• □ The packaging and shelf life reasoning is attached.
• □ For the simplified pathway, the summaries are retained and the raw data are kept on file.
• □ The labelling sterilisation symbols are scheduled against NOM-137-SSA1-2025.

Legal information verified as of 28 October 2026.

How GRZAN can help. GRZAN provides medical device and IVD registration, quality system, authorised representative and local testing support for the Mexican market. Our team manages COFEPRIS registrations and equivalence (equivalencia) reviews, coordinates third-party authorised centre routes, and supports post-market vigilance obligations. Business enquiries: info@grzanglobal.com