Using default methodologies to derive an acceptable daily exposure (ADE)

Area of Science:

• Pharmaceutical Science
• Toxicology
• Drug Development

Background:

• Establishing health-based acceptable daily exposure (ADE) typically requires comprehensive nonclinical and clinical data.
• In early drug development, limited or absent data necessitates alternative approaches for ADE derivation.
• Default methods provide crucial decision-making support when chemical-specific health effect data is lacking.

Observation:

• Various default ADE approaches exist, including toxicity estimates, fractions of therapeutic dose, cleaning limits, Threshold of Toxicological Concern (TTC), and Occupational Exposure Banding (OEB).
• Each method has unique derivation, application, strengths, and limitations that must be considered.
• These default strategies are employed when faced with toxicological and clinical data gaps.

Findings:

• Default ADE methods must be as protective, or more so, than those derived from complete data packages to ensure patient safety.
• Approaches like TTC and OEB, grounded in toxicological data, are preferred for early development ADEs.
• Reliance on these toxicological data-based defaults supports decision-making while further data is collected.

Implications:

• The use of validated default ADE approaches is critical for safeguarding patient health during early-stage drug development.
• Hazard banding tools and TTC provide robust frameworks for managing risks associated with data-poor compounds.
• Standardizing the application of protective default ADE strategies can enhance regulatory compliance and drug safety assessments.