A single intravenous infusion of 4.5 mg/kg of the new antineoplastic drug platidium induces structural-metabolic changes in the liver of rats (necrosis of hepatocytes, decrease of the glycogen and RNA content and accumulation of lipids in the cytoplasm of the hepatic cells, and increased activity of aspartate- and alaninaminotransferase in blood serum). An additional toxic factor (CCl4) applied one month after platidium infusion revealed incompleteness of reparative processes in the liver. The hepatoprotector essentiale weakens the injurious effect of the cytostatic on the hepatocytes and stimulates regeneration of the liver.