Case study 6. Transporter case studies: in vitro solutions for translatable outcomes.

Area of Science:

• Pharmacology and Drug Development
• Biochemistry and Molecular Biology

Background:

• Drug transporter interactions are critical for new drug candidate assessment.
• Regulatory agencies (FDA, EMA) require evaluation of multiple clinically relevant transporters.
• Drug transporters exhibit broad and overlapping specificities, complicating assessment.

Purpose of the Study:

• To highlight the complexities in evaluating drug candidate interactions with transporters.
• To guide the selection of appropriate in vitro test systems and probe substrates.
• To illustrate the interpretation of in vitro data for both uptake and efflux transporters.

Main Methods:

• Review of regulatory requirements for transporter interaction studies.
• Discussion of various in vitro test systems and their advantages/disadvantages.
• Analysis of case examples involving transporter kinetics and drug interactions.

Main Results:

• No single test system or probe is universally applicable due to transporter complexity.
• Multiple test systems and probes may be necessary for comprehensive evaluation.
• Successful interpretation of in vitro data is key to predicting clinical relevance.

Conclusions:

• Accurate assessment of drug-transporter interactions demands a nuanced understanding of available tools.
• Optimal in vitro experimental design is essential for regulatory submissions and predicting clinical outcomes.
• Further research and data are needed to fully elucidate transporter kinetics and drug interactions.