Anti-inflammatory, analgesic and antipyretic activities of loxoprofen sodium given intramuscularly in animals

A cyclic brush zwitterionic polymer based pH-responsive nanocarrier-mediated dual drug delivery system with lubrication maintenance for osteoarthritis treatment

Enhanced joint synergistic lubrication combined with anti-inflammatory therapy is an effective strategy to delay the progression of early osteoarthritis (OA) but has been rarely reported. The hydration lubrication of zwitterions and inherent super-lubrication properties of the cyclic brush, as well as the enhancement of the steric stability of the cyclic topology, can effectively improve the drug loading and utilization; herein we report a pH-responsive cyclic brush zwitterionic polymer (CB) with SBMA and DMAEMA as brushes and a cyclic polymer (c-P(HEMA)) as the core template, possessing a low coefficient of friction (0.017). After loading with hydrophobic curcumin and hydrophilic loxoprofen sodium it demonstrates high drug-loading efficiency. In vitro and in vivo experiments confirmed the triple function of the CB on superlubrication, sequence controlled release and anti-inflammatory effects demonstrated by Micro CT, histological analysis and qRT-PCR. Overall, the CB is a promising long-acting lubricating therapeutic agent, with potential for OA treatment or other diseases.

The effect of ion-pair formation combined with penetration enhancers on the skin permeation of loxoprofen

CONTEXT

Loxoprofen (LOXO) is a non-steroidal anti-inflammatory drug. Repeated oral administrations induce gastrointestinal side effects. Patches are a promising alternative.

OBJECTIVE

The aim of this study was to investigate the effects of organic amines on the skin permeation of LOXO and finally design a patch with a comparable permeation profile and pharmacodynamic effects to the commercial LOXONA® plaster.

MATERIALS AND METHODS

The effects of organic amines were assessed by flux values of LOXO from isopropyl myristate (IPM), using horizontal diffusion cell and rabbit skin. FTIR spectroscopy was used to confirm ion-pair formation. Anti-inflammatory and analgesic activity assessments were performed in the adjuvant arthritis rat model and acetic acid-induced writhing syndrome in mouse, separately.

RESULTS AND DISCUSSION

Results showed that triethylamine (TEA) was the most potential candidate in IPM, with the highest flux of 499.75 ± 32.40 µg/cm(2)/h. In patch, the highest flux of 369.37 ± 34.32 µg/cm(2)/h was still obtained by LOXO-TEA. Combined with penetration enhancers, the cumulative amounts were further increased in presence of 5% IPM, which exhibited a flux of 840.04 ± 66.38 µg/cm(2)/h as two times of the commercial one. Ultimately, anti-inflammatory and analgesic activity assessment presented that a comparable pharmacodynamic activity with the commercial one could be obtained by the patch we designed. Additionally, we also found that LOXO patch applied topically exerted a systemic effect, and the effect was dose-dependent.

CONCLUSION

It was feasible for LOXO patch design by combination of ion-pair technology and chemical enhancers.