Design of a novel felbinac cataplasm with high permeability for the treatment of arthritis

Abstract

The purpose of this study was to design a novel felbinac cataplasm with higher permeability than commercial product SELTOUCH® through using chemical enhancer strategy to reduce the times of administration and improve the compliance of patients. The novel felbinac cataplasm with high adhesion and good biocompatibility was prepared by calendar coating method. On the basis of previous research, the high-performance liquid chromatography (HPLC) analytical method of felbinac was established. According to 2020 Chinese pharmacopoeia (Ch. P), the paddle plate method was used to study the in vitro dissolution. The results showed the release of drug from self-made felbinac cataplasm could reach 90%. Subsequently, the effects of different kinds of penetration enhancers (N-methylpyrrolidone (NMP), isopropyl myristate (IPM) and propylene glycol (PG)) with the same percentage on the penetration of felbinac cataplasm were investigated. Propylene glycol (PG) was proved to be the most effective permeation enhancer among them. After screening different percentages of PG, 1% was added as the amount of permeation enhancer and the 12 h cumulative permeation amount was 189.03 µg/cm2 which was two times of the reference cataplasm (94.44 µg/cm2). The self-made felbinac cataplasm also had good stable permeability after placing at room temperature for 4 months. Finally, the tissue distribution study showed no matter in plasma, skin or muscle, the drug concentration of self-made cataplasm group was higher than reference cataplasm group. These data indicated that the self-made cataplasm provided a new reference for the development of felbinac dosage forms and promising alternative strategy for arthritis therapy.