Physicochemical and Microbiological Stability of Vancomycin 10-mg/mL Intravitreal Syringes

Area of Science:

• Ophthalmology
• Microbiology
• Pharmaceutical Science

Background:

• Bacterial endophthalmitis is a critical medical emergency requiring prompt treatment to prevent blindness.
• Standard treatment involves intravitreal injections of vancomycin and ceftazidime to cover a broad spectrum of bacteria.

Purpose of the Study:

• To assess the physicochemical and microbiological stability of vancomycin 10 mg/mL in intravitreal syringes.
• To determine optimal storage conditions for maintaining an immediate stock of vancomycin for clinical use.

Main Methods:

• Vancomycin 10 mg/mL syringes were stored at various temperatures (room temperature, 4°C, -20°C) for six months.
• Concentration, osmolarity, and microbiological growth were evaluated.
• An accelerated degradation study at 42°C for 51 days assessed concentration changes.
• High-performance liquid chromatography (HPLC) was used for concentration quantification.

Main Results:

• Vancomycin 10 mg/mL in polypropylene syringes demonstrated chemical, physical, and microbiological stability for up to six months when stored at -20°C.
• Stability was maintained for 14 weeks when stored at 4°C.
• Accelerated degradation studies at 42°C provided further insights into long-term stability.

Conclusions:

• Pre-filled vancomycin syringes offer a stable formulation for extended storage.
• Storage at -20°C allows for a six-month shelf-life, while 4°C storage provides a 14-week shelf-life.
• These findings support the development of readily available vancomycin stocks for emergency ophthalmic care.