Levofloxacin Hemihydrate In Situ Gelling Ophthalmic Solution: Formulation Optimization and In Vitro and In Vivo...

Area of Science:

• Ophthalmology
• Pharmaceutics
• Drug Delivery Systems

Background:

• Bacterial conjunctivitis necessitates frequent topical drug administration.
• Conventional eye drops have poor bioavailability (<10%) due to rapid precorneal elimination.
• Developing sustained-release ophthalmic solutions can enhance therapeutic outcomes.

Purpose of the Study:

• To design and evaluate an ion-sensitive, in situ gelling ophthalmic solution of levofloxacin hemihydrate (LFH).
• To improve ocular drug bioavailability and therapeutic efficacy for bacterial conjunctivitis treatment.

Main Methods:

• Gellan gum was utilized as an ion-sensitive in situ gelling agent for levofloxacin hemihydrate formulations.
• Formulations were screened for in vitro gelation time, drug release, and stability.
• Pharmacokinetic studies were conducted in New Zealand white rabbits, comparing with a commercial solution.

Main Results:

• The optimized formulations demonstrated rapid in vitro gelation (<15 s) and prolonged drug release (18-24 h).
• Formulations were stable for at least 6 months under various storage conditions.
• In vivo studies showed significantly increased AUC0-24 (22,660.39 h ng/mL) and MRT (12 h) compared to the commercial product.

Conclusions:

• In situ gelling ophthalmic solutions containing levofloxacin hemihydrate offer a promising drug delivery system.
• This approach enhances therapeutic efficacy and patient compliance for bacterial conjunctivitis treatment.
• The developed formulation represents an improvement over conventional topical eye drops.