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Development and validation of minimal disease activity, disease flare, and minimal clinically important difference
Farzana Nuruzzaman1, Natalie Rosenwaser2, Xing Wang3
1Division of Pediatric Rheumatology, Renaissance School of Medicine, Stony Brook University, Stony Brook, NY, USA.
Insights
New definitions for minimal disease activity (MDA), flare, and minimal clinically important difference (MCID) in chronic nonbacterial osteomyelitis (CNO) were established. These criteria are crucial for future clinical trials evaluating CNO therapies.
Area of Science:
- Rheumatology
- Pediatric Rheumatology
- Immunology
Background:
- Chronic nonbacterial osteomyelitis (CNO) requires standardized outcome measures.
- Current definitions for disease activity, flare, and clinically meaningful improvement are lacking.
Purpose of the Study:
- To establish consensus definitions for minimal disease activity (MDA), flare, and minimal clinically important difference (MCID) in CNO.
- To provide criteria for evaluating treatment efficacy in CNO clinical trials.
Main Methods:
- A panel of 20 CNO experts and 7 patients/caregivers utilized a group consensus voting technique.
- Data from an international observational CNO registry across three cohorts were analyzed.
- Consensus required at least 80% agreement among participants.
Main Results:
- Key variables for defining MDA, flare, and MCID were identified through general surveys.
- A ≥30% improvement in critical parameters and a ≥3-point increase in the CNO Clinical Disease Activity Score were deemed meaningful.
- Consensus data supported these quantitative thresholds.
Conclusions:
- Preliminary definitions for MDA, flare, and MCID in CNO have been established.
- These definitions can serve as targets and outcome measures for CNO therapies.
- Further validation in diverse cohorts and testing in clinical trials are necessary.
Objectives:
To create definitions for minimal disease activity (MDA), flare, and minimal clinically important difference (MCID) for chronic nonbacterial osteomyelitis (CNO). It is necessary to establish these criteria before starting clinical effectiveness trials for therapies in CNO.
Methods:
Three separate cohorts' samples from an international observational CNO registry were presented to a panel of 20 experts in CNO, including 7 patients/caregivers via online and in-person voting using the group consensus voting technique to define MDA, flare, and MCID, respectively. Experts classified the cases in each cohort as meeting the state for that specific cohort, ie, MDA or not, or flare or not, or meeting MCID or not. A consensus of ≥80% was required.
Results:
General surveys identified the most important variables to include to define MDA, flare, and MCID. Clinical improvement of ≥30% in these critical parameters and improvement of the CNO Clinical Disease Activity Score by at least 3 were considered meaningful by providers and consensus data.
Conclusions:
This study provides the preliminary definitions of MDA, disease flare, and MCID in CNO, which can serve as targets and potential outcomes from treatments. These definitions must now be validated in other cohorts and tested in clinical trials.