The introduced bis-lactobionic acid amides represent a new group of synthetic polyanions with a molecular weight of 2387 to 2514d. The compounds are homogeneous and chemically defined. 2. The in vitro blood coagulation parameters (APTT, Heptest, anti-Xa, thrombin time, and anti-IIa) are only marginally altered by these compounds. 3. In a rat model of venous thrombosis using endothelial damage as the thrombogenic stimulus, the antithrombotic activity of the bis-lactobionic acid amides was shown in a dose- and time-dependent manner. 4. LW 10082 and LW 10121 prolong the bleeding time at dosages about 10 times less than that of heparin. The safety/efficacy index appears to be wider for these compounds than for heparin. 5. In subchronic toxicologic studies in rats, LW 10082 was well tolerated up to a dosage of 100 mg/kg body weight. 6. The anticoagulant and antithrombotic activities of the bis-lactobionic acid amides decrease gradually with the increasing number of methylene groups in the alkylene chain.
