Effect of particle dissolution rate on ocular drug bioavailability

Area of Science:

• Ophthalmology
• Pharmaceutics
• Drug Delivery

Background:

• Aqueous ophthalmic solutions have low bioavailability due to tear drainage, turnover, and absorption.
• Drug suspensions may enhance bioavailability but require consideration of dissolution rate, solubility, and residence time.
• The interplay of factors influencing ophthalmic drug suspension dissolution has not been fully elucidated.

Purpose of the Study:

• To develop and validate a kinetic model for predicting ocular drug concentrations from suspensions.
• To investigate the impact of particle size, drug concentration, and drainage rate on ocular drug levels.
• To establish a predictive tool for optimizing ophthalmic drug suspension formulations.

Main Methods:

• Development of a novel kinetic model for ocular drug delivery from suspensions.
• Testing the model using fluorometholone, a steroid drug suspension.
• Simulating the effects of varying particle size, concentration, and drainage rates.

Main Results:

• The developed kinetic model successfully predicts ocular tissue drug levels for suspensions.
• The model demonstrates the influence of particle size, concentration, and drainage on drug bioavailability.
• A reasonable a priori prediction of drug levels is achievable with the proposed model.

Conclusions:

• The kinetic model provides a valuable tool for understanding and predicting ocular drug levels from suspensions.
• This model can aid in the rational design of ophthalmic drug suspensions with improved bioavailability.
• Further research can refine the model for broader applications in ophthalmic drug development.