1. Testing Your Device: What the FDA Looks For

2. Bio Vice President, Regulatory and Clinical Affairs MCRA
Graduated Tulane University in Biomedical Engineering; MS in Bioengineering Clemson
Develop comprehensive regulatory strategies for complex musculoskeletal devices and biologics
Review and write regulatory submissions (510(k)s, IDEs, PMAs) for orthopedic, spinal, and biological companies across the world
Design and implement mechanical, biomechanical, and animal testing and clinical study strategy and initiation for orthopedic and spinal companies
Former Branch Chief, Orthopedic Devices Branch, DSORD, CDRH
Former Spine Team Leader, DSORD, CDRH
Developed and/or reviewed over 1,000 submissions
MCRA
Current Consultant to 200 Companies
Founded February 25, 2004
36 Employees and Independent Experts
Offices in Washington, DC  New York  Connecticut
My name is Rosco Barthalemew Glennius Quissenart Stiegman
Integrated Services: US & International Regulatory, Reimbursement , Compliance, Clinical Services  Quality Assurance

3. Background 510(k) Concept
Demonstration of substantial equivalence of your device to a valid predicate
What’s a valid predicate?
A spinal system that is currently being used in the same fashion (intended use) for the same indications
Need to demonstrate equivalency in design and performance
Examples: material, mechanical characteristics, mechanism of action, sizes, sterilization, labeling
If “significant” difference, burden on company to demonstrate the risks of the differences can be mitigated.
Need to focus on stiffness, yield load, ultimate load, and failure mode
May need to have side by side testing
Have to demonstrate substantial equivalence in 2 cycles
“3 Strikes and you’re out” (original submission + 2 responses)

4. Demonstrating Mechanical Equivalence
Points to Consider
When developing testing protocol and plan, consider:
Case Material
Worst Case Size
Other Worst Case Considerations
Design Features
Mechanism of Action
Failure Modes
Wear Capabilities
Non-Standardized Testing
Demonstrating Substantial Equivalence

5. Materials & Sizes What the FDA Looks for
Test the worst case material for each test
What does that mean?
Weakest material – Polymer versus Metal
Depends on the test!
Higher stiffness but lower yield?
Higher yield due to lower stiffness?
Most devices use same material; so material selection not common
Test the worst case size for each test
Smallest size usually worst case
Depends on the test
FDA: Tall device for torsion vs smallest footprint for compression
FEA becoming more popular: Taller devices can have more holes/visualization windows, confounds basic mechanics
Interbody Cage: Dual cages or single cage?

6. Other Considerations What the FDA Looks for Sterilization
Device must be fully sterilized
If different sterilization processes used, which process is more-worst case?
FDA very sensitive to gamma sterilization of polymers
Laser Marking
Demonstrate laser marking does not affect performance
Size vs. Indication
AIS indications: pediatric population
Larger screws too big for anatomy
Small screws too small for skeletally mature
Coatings
HA on polymer?
Porous coating on metal?
Nitinol?

7. Justify All Testing, Sizes, and Constructs
Design Features
What the FDA Looks for
Constructs (ASTM F1717)
Standard 76mm length for pedicle screw systems
Does system include offset connector? Transverse connector?
Cages (ASTM F2077)
FEA more common to identify worst-case
Basic mechanics less reliable to predict worst-case height due to holes
Anterior Cervical Plates (ASTM F1717)
Screw back-out prevention
TDRs (ASTM F2423)
Design dependent, but smallest insert or size usually worst-case
OCT (ASTM F2706)
Plate, hooks, screws?
Justify All Testing, Sizes, and Constructs

8. Characterize how the device works
Mechanism of Action
What the FDA Looks For
Characterize how the device works
Testing must be compared to predicate device with same indications and intended use
How does the device stabilize the spine?
Interbody
Screws
Blades
Nothing
Interspinous
Anterior/Posterior
Just because in same anatomical location, the treatment effect difference
Example: Interspinous Devices can not be compared to pedicle screws
Example: Interbody cage with screws compared to interbody cage w/no screws

9. Characterize how the device breaks/fails
Failure Modes
What the FDA Looks For
Characterize how the device breaks/fails
Demonstrating better results not good enough
Began with Dynamic Stabilization Devices
FDA expects failure modes to be identical to predicate devices
Common failure modes
Screw breakage
Rod bending
Cage cracking
“Bone” fracture
New failure mode?
Usually due to novel design feature or material
Company must present risk assessment proactively
FDA may request clinical data

10. When is wear data needed?
Wear Considerations
What the FDA Looks For
When is wear data needed?
Articulating devices or mixed-material devices
Example: Cages with screws
Titanium alloy screws interfaced with PEEK cage
Wear in compression, torsion, compression-shear
TDRs
Usually softer articulating surface (e.g., PE on metal) wears
Standards dictate tested wear pattern
Metal on metal?
Must address wear specific to the tested material
Has to be same material
Limited published data to address wear safety
If no public information available, rabbit neurotoxicity study with same wear particulate needed

11. Non-standardized testing
What the FDA Looks For
Purpose
Substantial Equivalence?
Safety?
Testing for a 510(k)
Non-standard testing requires predicate to be tested side-by-side
Or ability to recreate “unique” testing with reference to results
Occasionally, FDA asks for specific test to address specific issue
Bottom-line: Need for non-standardized testing = difficult SE argument
Testing for an IDE
Need to demonstrate safety
Non-standard testing more prevalent since standards don’t exist yet for newer devices (e.g., interspinous process devices)
Must justify test set-up, protocol, results based on worst-case expected, clinically relevant loading/motion

12. Demonstrating Substantial Equivalence
What the FDA Looks For
FDA’s Questions:
Is there a valid predicate?
Does predicate have same indications and intended use?
How does the design compare to the predicate?
How does the device perform compared to the predicate?
Was standard method used?
If deviations, how does it affect results and comparisons
Was worst-case device tested?
Mechanical results comparison to predicate a MUST
Reviewers tend not make comparisons on their own
Seek Assistance Because Setting a Bad Precedent Could Kill a Submission

13. Thank you