Mini-tablets versus pellets as promising multiparticulate modified release delivery systems for highly soluble drugs

Area of Science:

• Pharmaceutical Sciences
• Drug Delivery Systems
• Materials Science

Background:

• Mini-tablets (≤6mm diameter) classification as single- or multiple-unit dosage forms remains ambiguous.
• Lack of standardized pharmacopoeial evaluation procedures for mini-tablets hinders their development.
• Venlafaxine hydrochloride (Vx), an antidepressant with poor bioavailability, was chosen as a model drug for controlled release studies.

Purpose of the Study:

• To evaluate mini-tablets as oral controlled delivery systems.
• To compare the performance of mini-tablets with pellets using venlafaxine hydrochloride.
• To assess the manufacturing, stability, and economic viability of mini-tablets versus pellets.

Main Methods:

• Formulation of venlafaxine hydrochloride-loaded mini-tablets and pellets with varying polymer hydrogel cores and ethyl cellulose coatings.
• Comparative in vitro drug release studies of mini-tablets, formulated pellets, and Effexor®XR pellets.
• Assessment of formulation stability and manufacturing considerations.

Main Results:

• Mini-tablets exhibited extended Vx release (<60% at 8h), comparable to Effexor®XR pellets.
• Pellets required significantly thicker coatings for equivalent drug release retardation compared to mini-tablets.
• Mini-tablets demonstrated superior storage stability and advantages in manufacturing, quality, and cost-effectiveness.

Conclusions:

• Mini-tablets are a viable and advantageous alternative to pellets for oral controlled drug delivery.
• The study highlights the need for standardized pharmacopoeial evaluation methods for mini-tablets.
• Mini-tablets offer improved drug release control, stability, and industrial feasibility.