Long term physicochemical stability study of novel ophthalmic formulations combining ceftazidime and vancomycin with and without cyclodextrins

Abstract

Ceftazidime (CZ) and Vancomycin (VM) are used to treat bacterial keratitis; however, their physicochemical incompatibility does not allow their co-administration. This incompatibility can be managed by buffering the mixture at an alkaline pH or by using cage molecules such as cyclodextrins (CD). The objective of this work was to compare the stability during 168 days of frozen storage of two formulations combining VA and CZ at a final concentration of 25 mg/mL: a CD-free formulation, at a pH=8.5 and a formulation with CD.

Keywords

• cyclodextrins
• vancomycin
• ceftazidime
• ophthalmic solution
• physicochemical stability
• bacterial keratitis