Preclinical Bioavailability Strategy for Decisions on Clinical Drug Formulation Development: An In Depth Analysis

Area of Science:

• Pharmaceutical Sciences
• Drug Development
• Biopharmaceutics

Background:

• A Biopharmaceutical Classification System (BCS)-like decision tree was previously proposed to guide clinical formulation development.
• This system relies on preclinical bioavailability data from solution and suspension formulations.

Purpose of the Study:

• To validate a proposed BCS-like decision tree for clinical formulation strategy.
• To assess the predictive value of in vitro criteria (solubility, permeability, dose number) for reducing animal studies.
• To evaluate the utility of preclinical bioavailability data in guiding formulation development.

Main Methods:

• Retrospective analysis of 89 Janssen compounds, including bioavailability data (Fabs,sol and Frel,susp/sol) in rats and dogs.
• Evaluation of Biopharmaceutical Classification System (BCS) classification based on solubility in biorelevant media.
• Analysis of clinically tested formulations for 12 Janssen compounds using the proposed decision tree.
• Assessment of the dose number (Do) for a standard human dose (100 mg).

Main Results:

• Bioavailability in dogs correlated well with BCS-like classification based on API solubility.
• The rat model showed less clear alignment between bioavailability and BCS classification.
• The animal bioavailability-based decision tree successfully guided oral formulation type selection, with dogs being the most discriminative species.
• Dose number calculations suggested similar formulation types but did not differentiate between solubility-enhancing or enabling formulations or account for API permeability.

Conclusions:

• A BCS-like decision tree utilizing preclinical bioavailability data, especially from dogs, effectively guides clinical formulation development.
• Early in vitro data (solubility, permeability), preclinical bioavailability, and pharmacokinetic parameters strengthen formulation decisions.
• For compounds with high dose numbers or low bioavailability, evaluating conventional and solubility/permeability-enhancing formulations in early human studies is crucial to avoid overinvestment in complex technologies.