Isolation of the proteinases inhibitors, available for medicinal purposes, was described, where the inhibitor of the Kunitz type was obtained from bovine pancreas and the inhibitor of the Bowman-Birk type from soybeans. Screening of the immobilization procedures was carried out, which enabled the authors to produce the polymeric conjugates of the proteinase inhibitors exhibiting the maximal rate of activity against pancreatic proteinases and granulocyte elastases. Pharmacokinetics of the proteinase inhibitors obtained was studied. High molecular derivatives of the inhibitors from the bovine pancreas circulated in rat blood in larger quantities and longer, their total clearance was 5 times than native inhibitor preparations. The preparations containing these inhibitors from bovine pancreas exhibited a high therapeutic efficiency in treatment of rats with hemorrhagic pancreatitis and acute liver failure in rabbits.