In Vitro-In Vivo Correlation (IVIVC) in Transdermal Drug Delivery Systems: Models, Regulatory Perspectives and...

Area of Science:

• Pharmacology and Pharmaceutical Sciences
• Biomedical Engineering
• Drug Delivery Systems

Background:

• Transdermal drug delivery systems (TDDS) offer advantages like avoiding first-pass metabolism but face challenges in development and regulation due to skin variability.
• In vitro-in vivo correlation (IVIVC) is crucial for linking in vitro data to systemic outcomes, aiding formulation and regulatory processes.

Purpose of the Study:

• To provide a comprehensive analysis of IVIVC in TDDS, covering methodologies, modeling, regulatory aspects, and challenges.
• To highlight the limitations of empirical correlations and the advantages of mechanistic and PBPK models for TDDS.

Main Methods:

• Review of experimental methodologies for IVIVC in TDDS.
• Analysis of mechanistic and physiologically based pharmacokinetic (PBPK) modeling strategies.
• Examination of regulatory perspectives and case studies on IVIVC in TDDS.

Main Results:

• Classical empirical IVIVC models often fail for TDDS due to factors like lag time and nonlinear absorption.
• Mechanistic and PBPK models demonstrate greater robustness in predicting transdermal behavior by incorporating skin physiology and formulation effects.
• Predictive IVIVC is achievable but depends heavily on standardized methods, model validity, and accurate physiological representation.

Conclusions:

• IVIVC for TDDS is best viewed as a continuum of translational strategies, not a binary outcome.
• Mechanistic and PBPK approaches are essential for advancing predictive and regulatorily accepted IVIVC models for next-generation transdermal therapeutics.
• Addressing knowledge gaps in standardization and physiological representation is key for robust TDDS IVIVC.