A Study of the Comparability of the Pharmacodynamic, Toxicological, and Pharmacokinetic Properties of the Reference Drug Pulmozyme® and the Biosimilar Drug Tigerase®

The article presents the results of studies of the drug Tigerase® (inhalation solution manufactured by JSC GENERIUM, Russia), conducted to obtain evidence of its similarity (comparability) to the reference drug Pulmozyme® (inhalation solution, manufactured by Hoffmann-La Roche Ltd., Switzerland). Both drugs contain human recombinant deoxyribonuclease I (dornase alfa) as an active substance and are intended for the treatment of cystic fibrosis with pulmonary manifestations (mucoviscidosis). The enzymatic activity of dornase alfa, contained in the studied drugs, was investigated in vitro and ex vivo on samples of purulent sputum of patients. The pharmacokinetic parameters of the drugs in the blood serum, bronchi, and lungs, as well as the main physiological parameters (body weight and temperature, the state of the cardiovascular, respiratory, excretory systems, hematological and biochemical blood parameters, pathomorphological changes in internal organs (including the state of the cornea), and mortality rates) were investigated in comparative studies of subchronic toxicity in juvenile and mature rats with 28-day inhalation at doses of 0.2 mg/kg for mature animals and 0.26 mg/kg for juvenile animals (the dose was 6 times higher than the dose recommended for clinical use). The results of the studies allow us to conclude that the drugs are comparable in enzymatic, mucolytic (secretolytic) DNase activity, safety profile and main pharmacokinetic parameters.