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Evaluation of dependent variable, time effect, covariates, and covariation structure in concentration-QTc modeling: A
Dalong Patrick Huang1, Shan Xiao2, Qianyu Dang1
1US Food and Drug Administration, Office of Biostatics, Office of Translational Sciences, Center for Drug Evaluation and Research, Silver Spring, MD, USA.
New drug safety analysis using concentration-QTc (C-QTc) modeling requires careful strategy. This study reveals that C-QTc models ignoring time effects can increase false negatives, impacting QTc prolongation risk assessment.
Area of Science:
- Pharmacology and Toxicology
- Clinical Trial Methodology
- Biostatistics
Background:
- The International Council for Harmonisation (ICH) E14 R3 guideline permits concentration-QTc (C-QTc) modeling for assessing drug-induced QTc prolongation risk.
- Current C-QTc modeling approaches may not fully capture temporal dynamics of drug effects on the QT interval.
- Optimizing C-QTc modeling is crucial for accurate drug safety evaluations.
Purpose of the Study:
- To evaluate the performance of various C-QTc modeling strategies under different conditions.
- To assess the impact of including time effects in C-QTc models.
- To identify optimal C-QTc modeling approaches for reliable QTc prolongation risk assessment.
Main Methods:
- A simulation study was conducted to compare different C-QTc models.
- Models varied in dependent variables (e.g., ΔQTc), covariates, and covariance structures.
- Performance was evaluated based on the control of false negative and false positive rates.
Main Results:
- C-QTc models using ΔQTc as the dependent variable without time effects demonstrated an inflated false negative rate.
- The choice of dependent variable, covariates, and covariance structure significantly influenced the control of false positive and false negative rates.
- Specific C-QTc modeling strategies were identified as superior for managing these error rates.
Conclusions:
- Appropriate C-QTc modeling is essential for accurate assessment of QTc prolongation risk.
- Incorporating time effects into C-QTc models is recommended to avoid inflated false negative rates.
- The study provides recommendations for C-QTc modeling strategies that effectively control both false negative and false positive rates in drug development.
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