Permitted Daily Exposure Values: Application Considerations in Toxicological Risk Assessments

Area of Science:

• Pharmaceutical Toxicology
• Drug Safety Assessment
• Risk Management

Background:

• Permitted daily exposure (PDE) values are utilized by toxicologists for qualifying impurities in drug substances and products.
• Understanding the limitations of PDE values is crucial for their effective use in risk assessment.

Purpose of the Study:

• To provide an educational overview of the development and application of PDE values in toxicological risk assessment.
• To highlight the importance of comprehensive safety data analysis and the appropriate selection of toxicity studies for PDE calculation.

Main Methods:

• Review of toxicological principles for impurity qualification.
• Analysis of safety data from proxy impurities to illustrate PDE development.
• Discussion of the scope and limitations of PDE values in drug safety.

Main Results:

• PDE values are derived from comprehensive safety data and appropriate toxicity studies when genotoxicity is not a concern.
• PDE values primarily address systemic toxicity and may not be suitable for local toleration or reproductive endpoints.
• PDE values should not be conflated with analytical limits or acceptable impurity levels.

Conclusions:

• PDE values are valuable tools in drug safety risk assessment when used with a clear understanding of their limitations.
• Proper application requires thorough data evaluation, appropriate study selection, and recognition of PDE scope.
• This primer aims to enhance the effective and appropriate use of PDE values in pharmaceutical safety evaluations.