Novel in vitro PK (non-animal PK) Assay for Excipient/Vehicle Formulation Studies

Purpose. A newly developed assay was applied for fast in vitro screening of the effect of various vehicles (e.g., 2-hydroxypropyl-b-cyclodextrin (HP-b-CD), polyethylene glycol 400 (PEG400, etc.) on solubility and absorption of sparingly soluble compounds.

Conclusion. A new in vitro PK method facilitates studying of the complex role excipients play in absorption. Sometimes, individual measurements of permeability and solubility, a task that is especially tedious for sparingly soluble compounds, can be avoided. This practical, low-cost, and relatively high-throughput UV-based assay incorporates the advances achieved in Double-Sink™ PAMPA and is demonstrated to be useful in early lead-investigation screening for formulation effects on absorption.