Development of the composition of meloxicam gel based on the results of biopharmaceutical studies

Abstract

The meloxicam concentration and the composition of permeation enhancers in a gel for cutaneous application have been chosen on the basis of the results of pharmacological screening on the model of acute aseptic carrageenan inflammation of the rat’s paw. The efficiency of the analgesic effect of gels increases with increasing the meloxicam content, and the efficiency of the anti-inflammatory activity passes through a maximum at the meloxicam concentration of 1.0-1.5%. The efficiency of the anti-inflammatory and analgesic effects is the highest when gels contain 15% of N-methylpyrrolidone and 25% of ethanol (96%). Due to the content of hydrophilic non-aqueous solvents the gel base possesses the osmotic activity, whereby providing the moderate water absorption by the drug and prolonged release of meloxicam from the gel in experiments in vitro. Such properties of the gel, on the one hand, are an important prerequisite for transdermal absorption of meloxicam, on the other hand, the dehydrating action onto the skin is not expected. Pharmacokinetic studies of 1% gel of meloxicam were conducted compared to the intramuscular (i/m) administration of Movalis injection of 15 mg/1.5 ml. The analytical procedure (liquid chromatography with the solid phase extraction of the active substance from the plasma) has been developed and validated for analytical support of the pharmacokinetic studies. It has been found in the experiment on rabbits that in case of cutaneous application of the gel meloxicam is absorbed slowly and continuously into the systemic circulation at a relatively high extent of transdermal absorption and slow elimination. Therefore, it can be expected that the gel developed provides the effective prolonged therapeutic action.