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Beyond QSARs: Quantitative Knowledge-Activity Relationships (QKARs) for enhanced drug toxicity prediction
Ting Li1, Yanyan Qu1,2, Alexander Chen1
1National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, United States.
Quantitative Knowledge-Activity Relationships (QKARs) outperform traditional Quantitative Structure-Activity Relationships (QSARs) in predicting drug toxicity. QKARs leverage domain knowledge, improving accuracy for drug-induced liver injury and cardiotoxicity predictions.
Area of Science:
- Computational toxicology
- Drug safety assessment
- Artificial intelligence in pharmacology
Background:
- Quantitative Structure-Activity Relationships (QSARs) traditionally predict toxicity based on chemical structure.
- QSARs' structure-centric approach limits accuracy for drugs with minor structural changes but significant toxicity differences.
- Advances in AI offer new methods to integrate broader chemical knowledge for enhanced toxicity prediction.
Purpose of the Study:
- Introduce a novel framework, Quantitative Knowledge-Activity Relationships (QKARs), for predicting drug toxicity.
- Evaluate QKARs' performance against QSARs for drug-induced liver injury (DILI) and drug-induced cardiotoxicity (DICT).
- Explore the integration of knowledge-based and structure-based data for improved predictive accuracy.
Main Methods:
- Developed QKAR models using domain-specific knowledge representations for DILI and DICT.
- Applied five distinct machine learning algorithms to assess model complexity's impact on performance.
- Compared QKAR performance against QSARs using identical datasets and endpoints.
- Investigated combined knowledge and structure-based models (Q(K+S)ARs).
Main Results:
- QKAR models utilizing comprehensive drug knowledge showed superior prediction accuracy.
- Model complexity showed minimal association with performance across different machine learning algorithms.
- QKARs consistently outperformed QSARs for both DILI and DICT.
- QKARs effectively distinguished drugs with similar structures but varying liver toxicity profiles.
Conclusions:
- QKARs represent a robust alternative to traditional QSARs for drug toxicity assessment.
- Leveraging domain-specific knowledge significantly enhances toxicity prediction accuracy.
- Integrating knowledge-based and structure-based data offers further improvements in predictive modeling.
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