Novel flucytosine loaded in-situ gel for the management of ocular infections
DOI:
https://doi.org/10.56782/pps.350Keywords:
Flucytosine, Poloxamer 407, Gellan gum, HPMC K4M, In-situ ocular gel, Simplex lattice designAbstract
Flucytosine, a BCS class II drug, is indicated in fungal infection. Currently, flucytosine is available in tablet dosage form in the market. However, the drug is indicated for the ocular fungal infections. Thus, there is a need to develop a ocular formulation that can retain for longer duration with prolonged drug release. In the present work, in-situ ocular gel containing flucytosine was prepared for cryptococcosis and candidiasis fungal infection. Design of experiment was employed to obtain the optimized formulation. To determine the independent variables impacting the formulation preparation, preliminary trials were conducted using Poloxamer 407, Poloxamer 188, Carbopol 934, gellan gum, and HPMC K4M as polymer and it was optimized using Simplex lattice design. Amount of poloxamer 407, amount of gellan gum and amount of HPMC K4M were taken as independent variable while viscosity (cps), gelling time (sec), drug release in 6 h were taken as dependent variables. The prepared formulations were evaluated for clarity, pH, viscosity, gelling time, gelling strength, gelling temperature, in-vitro drug release, sterility test and stability studies. Results of the prepared in-situ ocular gel formulation of flucytosine demonstrated significant potential as a therapeutic breakthrough for enhancing treatment outcomes in candidiasis and cryptococcosis infections. Stability studies suggested formulation was stable for at least 6 months. Thus, a successful formulation of flucytosine was developed addressing critical challenges of conventional eye drops and offering prolonged drug release with improved retention in the eye.
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