ENHANCEMENT OF SOLUBILITY OF BCS CLASS II DRUG VIA TOPICAL DELIVERY FROM SUPERSATURATED DRUG DELIVERY SYSTEM: A NEWER APPROACH FOR THE TREATMENT OF OSTEOARTHRITIS

Abstract

The present research was aimed to develop topical supersaturated spray formulation for delivery of naproxen (BCS class
II drug) for the treatment of osteoarthritis. From saturated solutions of topical formulations, maximum drug flux is
achieved under ideal circumstances, therefore, the enhanced drug penetration through diffusion would expect from
supersaturated drug delivery systems. Nevertheless, upon penetration into skin, these supersaturated formulations tend
to crystallize because of the characteristic lack of stability, which might be overcome by adding anti nucleant polymers.
To delay or inhibit crystallization, Hydroxypropyl methylcellulose (HPMC) has been used in this study, which has also
been found effective in maintaining the high activity state at a high degree of saturation (DS). The solubility behavior of
naproxen in ethanol-propylene glycol (PG) mixtures was carefully evaluated by calculating the dielectric constant, as
well as various other physical properties. Supersaturated topical spray-on system for Naproxen was formulated by using
the co-solvency method, where 9:1 ethanol: PG ratio was used as a solvent. The prepared system was checked for all
physicochemical evaluations including stability and in vitro drug diffusion. In vitro study showed 99.95% drug release at
6 minutes. The optimized formulation passed stability study over a year. The supersaturated spray formulation developed
with ethanol/PG and HPMC E5 consequently epitomizes a boosting methodology targeting to increase stability as well as
the permeability flux of a BCS class II drugs.