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Dura Substitute Devices - Premarket Notification (510k) Submissions

This guidance provides recommendations for manufacturers submitting premarket notification (510(k)) for dura substitute devices, which are class II devices used to repair the dura mater (membrane surrounding the brain). It covers devices made from both synthetic and natural materials.

What You Need to Know? 👇

What are the key biocompatibility testing requirements for dura substitute devices?

Dura substitutes require cytotoxicity, sensitization, irritation, acute systemic toxicity, mutagenicity, and hemolysis testing. For devices remaining in the body over 30 days, additional subchronic (90-day) and chronic (180-day) toxicity studies with histological analysis are recommended.

How long should clinical follow-up be for dura substitute device studies?

Patients implanted with dura substitutes should typically be followed for one year. However, sponsors may justify shorter follow-up periods depending on similarities and differences to predicate devices, with appropriate scientific rationale provided.

What sterilization validation requirements apply to dura substitute devices?

Manufacturers must specify sterilization method, validation approach, sterility assurance level (SAL), lot monitoring methods, and packaging. A SAL of 10⁻⁶ is important unless scientifically justified. Viral inactivation must demonstrate at least 10⁶ fold reduction.

What animal-derived material documentation is required for dura substitutes?

For animal-derived materials, provide species/tissue source, herd health monitoring, vaccination records, veterinary inspections, feed composition, USDA-approved slaughterhouse certification, BSE-free country certification for bovine materials, animal age at sacrifice, and pre/post-mortem inspection details.

What are the essential animal study endpoints for dura substitute evaluation?

Animal studies must evaluate cerebrospinal fluid leakage, adhesion formation, implant anchorage, device resorption, vascularization, infection incidence, hydrocephalus, hemorrhage, foreign body reactions, and other tissue responses through histological assessment at the intended anatomical site.

For materials not previously used in neurological applications, randomized, concurrently controlled, multicenter clinical trials are recommended. The study should demonstrate similar performance to legally marketed predicate devices with adequate sample size based on expected adverse event incidence.


What You Need to Do 👇

  1. Develop comprehensive testing plan covering physical, mechanical, and biocompatibility requirements
  2. Design and execute animal studies at intended anatomic site
  3. Plan multicenter clinical trial if using novel materials
  4. Establish detailed manufacturing controls and specifications
  5. Validate sterilization process and stability
  6. Prepare comprehensive labeling including detailed surgical instructions
  7. For animal-derived materials, establish robust sourcing controls and documentation
  8. Develop product characterization protocols
  9. Create detailed documentation of all testing and validation activities
  10. Establish post-market surveillance plan for safety monitoring

Key Considerations

Clinical testing

  • Multicenter clinical trials required for materials not previously used in neurological applications
  • One-year follow-up typically required
  • Study should evaluate:
    • CSF leakage
    • Complications (intraoperative and postoperative)
    • Device effectiveness compared to predicate devices
    • Patient populations and inclusion/exclusion criteria clearly defined

Non-clinical testing

  • Physical and mechanical properties testing required:
    • Device thickness
    • Tensile strength
    • Suture retention strength
    • Burst strength
    • Shrink temperature range
    • Surface structure

Human Factors

  • Questionnaire recommended for investigators regarding ease of handling and device conformability

Biocompatibility

  • Testing required per ISO 10993-1:
    • Cytotoxicity
    • Sensitization
    • Irritation
    • Acute systemic toxicity
    • Mutagenicity
    • Hemolysis
  • Additional for >30 days implants:
    • 90-day subchronic toxicity
    • 180-day chronic toxicity

Labeling

  • Must include:
    • Specific indications for use
    • Target populations
    • Comprehensive instructions for:
      • Pre-implant training
      • Patient preparation
      • Implantation procedures
      • Follow-up care

Safety

  • Sterilization validation required with SAL of 10-6
  • Pyrogenicity testing (<0.06 EU/ml)
  • Stability testing for expiration dating
  • Animal studies at intended anatomic site required

Other considerations

  • For animal-derived materials:
    • Source species and tissue information
    • Herd health monitoring
    • BSE-free certification for bovine materials
  • Manufacturing process details
  • Product specifications and characterization

Relevant Guidances 🔗

  • ISO 10993-1: Biological evaluation of medical devices - Part 1: Evaluation and testing
  • ISO 10993-7: Biological evaluation of medical devices - Part 7: Ethylene oxide sterilization residuals
  • AAMI TIR-19: Guidance for ANSI/AAMI/ISO 10993-7

Original guidance

  • Dura Substitute Devices - Premarket Notification (510k) Submissions
  • HTML / PDF
  • Issue date: 2000-11-08
  • Last changed date: 2020-03-18
  • Status: FINAL
  • Official FDA topics: Medical Devices, Premarket
  • ReguVirta ID: 673d5ad11f7acd1a93f901c1cb6aed38
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