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Retinal Prostheses: Clinical, Non-Clinical, and Safety Recommendations for Electrical Stimulation Devices

This guidance is specifically focused on retinal prostheses that are implanted on or beneath the retina, or on/beneath the outer surface of the globe, using electrical stimulation to provide visual perception for people with degenerative retinal conditions. It does not apply to prostheses that stimulate the optic nerve, visual cortex, or other brain areas.

  1. Develop comprehensive pre-clinical testing plan including animal studies, durability testing, and biocompatibility evaluation
  2. Design clinical protocol with:
    • Clear inclusion/exclusion criteria
    • Defined safety and effectiveness endpoints
    • Statistical analysis plan
    • Long-term follow-up strategy
  3. Create detailed device description documentation including:
    • Engineering drawings
    • Material specifications
    • Software documentation
    • Manufacturing process description
  4. Establish risk management process and documentation
  5. Develop complete labeling package including:
    • Surgical procedure
    • Warnings and precautions
    • Patient information
    • Training materials
  6. Create sterilization validation protocol
  7. Prepare IDE submission package with all required elements
  8. Consider requesting Pre-Submission meeting with FDA to discuss study design and requirements

Key Considerations

Clinical testing

  • Follow subjects for minimum 3 years
  • Evaluate visual performance at intervals of max 3 months for first year, max 6 months thereafter
  • Include assessments of:
    • Visual function (acuity, grating, spatial mapping)
    • Functional vision in real-world situations
    • Patient reported outcomes
  • Use independent professionals for orientation/mobility assessments
  • Include statistical analysis plan with sample size justification

Non-clinical testing

  • Conduct animal testing on active finished device before human trials
  • Perform acute tests (24h) and long-term tests (6+ months) in animal models
  • Evaluate histology and device functionality post-explantation
  • Conduct accelerated lifetime tests for durability
  • Validate welding/bonding processes
  • Test flexion under simulated use conditions

Human Factors

  • Evaluate usability of portable controller
  • Assess tactile controls and indicators
  • Consider impact resistance and water resistance
  • Ensure ease of battery replacement
  • Validate all patient and clinician software

Software

  • Describe physician fitting software and patient controls
  • Include fail-safes and protection against programming errors
  • Validate software according to level of concern
  • Include resets/presets and device feedback mechanisms

Labelling

  • Include contraindications, warnings, precautions
  • Describe surgical procedure in detail
  • Provide patient information and implant card
  • Include electromagnetic compatibility warnings
  • Detail storage conditions and battery information

Biocompatibility

  • Provide material biocompatibility profiles
  • Conduct bacterial endotoxin testing
  • Perform leachables testing
  • Conduct pyrogen testing
  • Test material stability in saline environment

Safety

  • Identify primary safety endpoint
  • Track surgical complications and adverse events
  • Define acceptable risk levels
  • Report unanticipated adverse effects within 10 days
  • Monitor device hermeticity

Other considerations

  • ISO 15004-1:2006: Ophthalmic instruments - Fundamental requirements and test methods
  • IEC 60601-1-2:2001: Medical Electrical Equipment - Electromagnetic compatibility
  • ISO 10993-7: Biological Evaluation of Medical Devices - Ethylene Oxide Sterilization Residuals
  • ISO 17665-1:2006: Sterilization of health care products - Moist heat
  • ISO 11135-1:2007: Sterilization of health care products - Ethylene oxide
  • ISO 11607-1/2:2006: Packaging for terminally sterilized medical devices
  • ASTM F1980-07: Standard Guide for Accelerated Aging of Sterile Barrier Systems

Original guidance

  • Retinal Prostheses: Clinical, Non-Clinical, and Safety Recommendations for Electrical Stimulation Devices
  • HTML / PDF
  • Issue date: 2013-03-06
  • Last changed date: 2020-02-28
  • Status: FINAL
  • Official FDA topics: Medical Devices, Ophthalmic, Investigational Device Exemption (IDE)
  • ReguVirta summary file ID: e13dd67789cd29e513af7961e968e722
This post is licensed under CC BY 4.0 by the author.