Clinical Microbiology and Antimicrobial Chemotherapy. 2011; 13(4):335-345
Azithromycin is still one of the most frequently administered antimicrobials. In conditions of counterfeited generic drugs number steady growth in Russia, there is an obvious necessity of their pharmaceutical equivalence study. Objectives.
Comparison of quantitative amount and stability of azithromycin, detection of impurities and insoluble particle contamination in original Sumamed product (Pliva, Croatia) and two generic drugs (Azithral, Alembic Ltd, India, and Azinort, Neon Laboratories Ltd, India).
Nineteen vials of each commercial product were studied. Time of complete dissolution of vial content was measured for each vial. The active azithromycin amount and aqueous solution 12- and 24-hours stability at room temperature, as well as soluble impurities presence were studied by reversed-phase high performance liquid chromatography with UV-detection. Insoluble particle contamination was studied by filtration of azithromycin solution through analytical membranes.
The original Sumamed product (Pliva, Croatia) met all requirements for active substance amount, established active azithromycin quantity was 100.1%±1.9% of the claimed on the label. The generic Azithral product (Alembic Ltd, India) failed the requirements of British Pharmacopoeia for active substance amount, vials of this drug contain 94.3%±2.9% of declared azithromycin. Generic product Azinort, (Neon Laboratories Ltd, India) failed the requirements of British, European and American Pharmacopoeias for active substance amount, established quantity of azithromycin made up 89.3%±4.7% of declared. Duration of complete dissolution of Azithral flasks content takes four times longer than that for the brand product content (18.1 min vs 4.5 min, respectively); Azinort product showed similar to Sumamed time of dissolution (6 min). All three commercial drugs contained comparable quantity of soluble impurities and were free of particle contamination.