IN-SITU OPHTHALMIC GEL FORMING SOLUTION OF MOXIFLOXACIN HYDROCHLORIDE FOR SUSTAINED OCULAR DELIVERY

Human eye is a challenging subject for topical administration of the drugs because of its peculiar anatomical arrangements of surface tissue and impermeability of the cornea. Topical instillation of drugs through eye drops is the most important and well-accepted route of administration for the treatment of various eye disorders. Conventional ophthalmic drug delivery systems often result in poor bioavailability and therefore poor therapeutic response. Several new preparations have been developed to prolong the contact time of the medicament on the ocular surface. Successful results have been obtained with inserts and collagen shields. However, these preparations have some disadvantages, such as poor patient compliance, especially by geriatric patients. This problem can be overcome by using in situ gel forming systems of polymers that exhibit reversible phase transition. Such system can be formulated as eye drops suitable for administration by instillation into the eye, which upon exposure to the eye converts to the gel phase. The advantage of these formulations is that unlike inserts and films they do not require sophisticated equipments for manufacture and they are easily scalable. The objective of the present study was to develop an ion activated in situ gelling system for Moxifloxacin Hydrochloride, so as to increase the precorneal residence time, reduced dosing frequency and improved patient compliance. In situ gel forming solution of Moxifloxacin Hydrochloride was developed using Sodium Alginate (Keltone LVCR, Protanal®) as the gelling agent in combination with Hydroxypropyl Methylcellulose (HPMC)- Methocel E50LV which acted as a viscosity-enhancing agent. The  prepared  formulations  were  evaluated  for  pH , gelling  capacity,  drug  content,  in vitro diffusion studies, ex vivo diffusion studies, bioadhesion test, sterility and antimicrobial efficacy studies. Key Findings: The rheological behaviors of all formulations consisting of gelling polymer were not found to be affected by the incorporation of drug and sterilization. The developed formulation providedabout90% in vitro release and 85% ex-vivo release in 12 hours. Results of the present study indicate that Moxifloxacin Hydrochloride retained its antimicrobial efficacy when formulated as an in situ gelling system. Conclusion: In situ gel forming solutions developed for Moxifloxacin Hydrochloride using polymers like Sodium alginate and HPMC prolong the release and reduce dosing frequency of the drug. Thus, the developed in situ gel forming solution is an effective alternative for conventional ophthalmic drug delivery systems