Clinical Study Design and Benefit-Risk Considerations for Weight Loss Medical Devices (DRAFT)
This guidance provides recommendations for clinical study design and benefit-risk considerations for medical devices with indications associated with weight loss, including weight loss, weight reduction, weight management, or obesity treatment in patients who are overweight or have obesity.
This is a draft guidance. Not for implementation.
Recommended Actions
- Develop comprehensive clinical study protocol addressing:
- Study design and controls
- Patient selection criteria
- Duration and follow-up schedule
- Primary and secondary endpoints
- Adverse event monitoring and classification
- Statistical analysis plan
- Establish data safety monitoring board and endpoint adjudication committee
- Implement robust adverse event tracking system using modified Clavien-Dindo classification
- Create detailed plan for documenting and analyzing:
- Weight loss metrics (% TBWL, BMI changes)
- Adverse events and complications
- Device removals
- Patient-reported outcomes
- Consider submitting Q-Submission to FDA to discuss study design before implementation
- For pediatric studies, develop additional safeguards and monitoring procedures
- Use evaluation matrices to assess benefit-risk profile based on weight loss and adverse events
- Document all aspects needed for benefit-risk determination including:
- Clinical benefits (weight loss, comorbidity changes)
- Device and procedure risks
- Patient preference information
- Alternative treatment options
Key Considerations
Clinical testing
- Pivotal studies should be double-blinded, randomized, controlled trials (RCTs)
- Sham-controlled study recommended due to anticipated placebo effect
- No more than 50% of pivotal study data should be collected outside US
- Study duration and follow-up should be adequate based on indication:
- “Weight loss”: 12 months or more
- “Short term weight loss”: 6-12 months
- “Weight management”: less than 6 months
- Co-primary effectiveness endpoints recommended:
- Superiority margin of mean % total body weight loss over control
- Performance goal for responder rate based on individual subject success
Safety
- Adverse events should be classified using modified Clavien-Dindo system based on treatment required
- Data safety monitoring board (DSMB) recommended
- Independent endpoint assessment/adjudication committee recommended
- Document all adverse events and categorize as device-related, procedure-related, or not related
- Tabulate serious adverse events and unanticipated adverse device effects
- Document time to onset and duration of GI-related adverse events
- Track all unanticipated device removals and reasons
Other considerations
- For pediatric studies:
- Device should not be studied until adult data shows minimal risk
- Risk of permanent implant removal should be well defined
- Document history of failing lifestyle modification
- Include lead-in period to assess compliance
- Study duration minimum 12 months for permanent devices
- Screen for genetic causes of obesity
- Assess maturity level and psychosocial factors
Relevant Guidances
- Non-Clinical Testing Recommendations for Weight Loss and Obesity Treatment Devices (Draft)
- Design Considerations for Medical Device Pivotal Clinical Studies
- Benefit-Risk Determinations for Medical Device Premarket Review
- Patient Preference Information in Medical Device Development, Clinical Trials, and Regulatory Decision Making
Related references and norms
- ISO 14155: Clinical investigation of medical devices for human subjects - Good clinical practice
Original guidance
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