EVALUATION OF BIOPHARMACEUTICAL PARAMETERS OF A NEW INTRANASAL ANTIVIRAL DRUG BASED ON AN IN SITU SYSTEM

Abstract

Intranasal antiviral administration is a modern method for delivery of both immunobiological and synthetic substances. This route in medication delivery has a number of advantages: it is non-ivasive, highly practical, bioavailable and provides protective immunity at the entry gates of respiratory infections. The problem of intranasal delivery systems is short drug retention time under the effect of mucociliary clearance that results into limited absorbtion and prolongation capability. Аnatomical structure of the nasal cavity as well as the effect of mucociliary clearance result into an early evacuation of the administered drug so the active substance is not fully delivered. The solution to the problem is the usage of in situ delivery systems with stimulus typical for nasal cavity applied: temperature, ionic composition, pH. These systems make a phase transition at the area of application with viscosity increase enough for continuous effect on the mucous membrane. Earlier an intrasal ribavirin delivery system has been designed at the Institute of Pharmacy named after A. Nelubin. Ribavirin is an active substance known for more than forty years, approved by the FDA and included in the clinical guidelines for the treatment of diseases caused by SARS-CoV-2. The purpose of that research was to define the main biopharmaceutical parameters of the designed composition. The delivery system included ribavirin (10 mg/ml), poloxamer 407 – 16%, chitosan formate – 4%. The evaluation of biopharmaceutical characteristics was carried out according to the parameters рН, phase transition temperature, gelation time, viscosity, mucoadhesion and also spray torches, distribution area and retention on an in vitro model, releasing in the Franz cell test. Results of the evaluation of indicators: pH of the system – 7,07±0,12; sol-gel transition end temperature 30,7±0,4℃; gelation time - 36±15 s; increase in viscosity after phase transition - 7 times; mucoadhesion - 8,6±1,5 Н; distribution area - 44,9±5,3 cm2; retention on an in vitro model - 85,0±3,5%. During the determination of the release of ribavirin, it was shown that in the first 5 minutes about 62.5% is released, then the release is gradual and by six hours it reaches 84.7%. Based on the obtained data, it can be concluded that the developed composition is potentially promising and that it can be further evaluated in preclinical studies.