[Comparative evaluation using in vitro dissolution tests of various sustained release theophylline preparations]

Area of Science:

• Pharmaceutical Sciences
• Drug Delivery Systems
• Pharmacokinetics

Background:

• Sustained-release theophylline formulations are crucial for managing respiratory diseases.
• Evaluating dissolution profiles is essential for ensuring therapeutic efficacy and bioequivalence.
• New sustained-release theophylline formulations require rigorous comparison with existing market products.

Purpose of the Study:

• To compare the dissolution properties of two novel sustained-release theophylline tablets (A and B) against established market preparations.
• To assess theophylline release kinetics and determine if they align with optimal dissolution rates described in literature.
• To identify potential formulation differences affecting drug release for sustained-release theophylline.

Main Methods:

• Dissolution testing utilizing the rotating basket apparatus.
• Application of the "half-change" method for dissolution rate assessment.
• Comparative analysis against reference theophylline products (Theo-Dur, Euphyllin, Aminophyllinum-retard) and literature data.

Main Results:

• The sustained-release tablet B (150 mg theophylline) demonstrated dissolution characteristics consistent with market preparations and literature.
• The sustained-release tablet A (300 mg theophylline) exhibited a significantly slower dissolution rate compared to its market comparator.
• Dissolution profiles indicated that tablet A did not meet the optimal release rate criteria outlined in the literature.

Conclusions:

• Sustained-release tablet B (150 mg) shows promising dissolution properties comparable to existing theophylline products.
• Sustained-release tablet A (300 mg) requires formulation optimization to achieve desired theophylline release kinetics.
• Dissolution testing is a critical tool for quality control and development of sustained-release drug products.