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Clearance prediction for Amgen molecules against Extended Clearance Classification System (ECCS) and future
Prashant Agarwal1, Kazuya Ishida2, Darren L Reid1
1Drug Product Technologies, Process Development, Amgen, Inc., 360 Binney St, Cambridge, MA 02142 USA.
The Extended Clearance Classification System (ECCS) helps predict drug elimination pathways. Evaluating 42 Amgen molecules showed ECCS has limitations, requiring updates as drug development evolves.
Area of Science:
- Pharmacokinetics and Drug Metabolism
- Medicinal Chemistry
- Drug Discovery and Development
Background:
- Accurate prediction of drug elimination pathways is crucial for efficient drug discovery.
- The Extended Clearance Classification System (ECCS) offers a framework for identifying major drug elimination routes.
- ECCS aims to guide the development of new chemical entities by predicting their metabolic fate.
Purpose of the Study:
- To critically analyze the chemical space covered by the ECCS framework.
- To assess the applicability and limitations of ECCS in predicting major elimination pathways.
- To evaluate the performance of ECCS using a set of 42 Amgen small molecules.
Main Methods:
- Retrospective analysis of 42 Amgen small molecules using the ECCS framework.
- Evaluation of the ECCS framework's ability to predict the major elimination pathway for these molecules.
- Critical assessment of the chemical space defined by ECCS and its constraints.
Main Results:
- The study assessed the performance of the ECCS framework in retrospectively predicting elimination pathways.
- Analysis revealed constraints and limitations in the chemical space defined by the ECCS.
- The evaluation identified the need for periodic review and revision of the ECCS.
Conclusions:
- The ECCS framework shows potential but requires updates to remain relevant.
- Evolving drug development trends, driven by target constraints, are shifting molecules outside traditional 'drug-like' physicochemical spaces.
- Periodic review and revision of ECCS are essential to maintain its predictive accuracy and applicability in modern drug discovery.
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