Dissolution tests of pharmaceutical tablets using a novel gastric simulator

Area of Science:

• Pharmacology
• Biomedical Engineering
• Drug Delivery Systems

Background:

• Accurate in vitro drug dissolution testing is crucial for predicting in vivo performance.
• Existing methods like USP Apparatus 2 may not fully replicate the complex physiological environment of the human stomach.

Purpose of the Study:

• To develop and evaluate a new device, the in vitro Distal Gastric Simulator (IV-DGS), for simulating human gastric conditions.
• To compare drug dissolution profiles of standard tablets using the IV-DGS versus the United States Pharmacopeia (USP) Apparatus 2.

Main Methods:

• Prednisone USP compendial standard tablets were dissolved in two apparatuses: the IV-DGS and USP Apparatus 2.
• The IV-DGS simulated physiological conditions including peristaltic movement (3 cycles/min) and pressure (approx. 25 mm Hg).
• Dissolution data were modeled using first-order and Weibull models.

Main Results:

• After 12 minutes, USP Apparatus 2 showed 71.5% dissolution, while the IV-DGS achieved 24.9% dissolution.
• The IV-DGS demonstrated a slower dissolution rate but provided more realistic gastric mixing simulation.
• The Weibull model provided a better fit for the dissolution data from both systems.

Conclusions:

• The IV-DGS offers a more physiologically relevant alternative for in vitro drug dissolution studies compared to USP Apparatus 2.
• While results are not directly comparable, the IV-DGS provides valuable insights into drug behavior under simulated gastric conditions.
• Further validation is needed, but the IV-DGS shows promise for improving pre-clinical drug development assessments.