Short-Stability Study of Rifaximin-Based Samples.

Area of Science:

• Pharmaceutical Sciences
• Drug Delivery Systems
• Antimicrobial Agents

Background:

• Rifaximin, an oral antimicrobial (600-800 mg daily), is Biopharmaceutic Classification System Class IV.
• Rifaximin-based samples were developed using β-cyclodextrin complexation and wet milling to improve drug delivery.

Purpose of the Study:

• To assess the stability and integrity of novel rifaximin-based formulations.
• To evaluate the effectiveness of pharmaceutical technology in drug product development.

Main Methods:

• Stability studies conducted for 6 months under controlled temperature and humidity.
• Simultaneous analysis using High-Performance Liquid Chromatography (HPLC) and microbiological turbidimetry at 0, 3, and 6 months.

Main Results:

• Two formulations followed second-order kinetics, and one followed zero-order kinetics.
• Microbiological analysis was crucial for assessing rifaximin potency, yielding more consistent results than HPLC in one sample.

Conclusions:

• Rifaximin-based samples exhibited stability under controlled environmental conditions.
• Both physical-chemical and microbiological methods effectively monitored drug behavior over the study period.
• Developing these rifaximin formulations presents a financially attractive alternative to new drug discovery.