Abstract: The present invention relates to sulphated glycosamino glycuronan with antithrombotic activity consisting essentially of salts of dermatan sulphate, chondroitin sulphate and heparan sulphate, characterized bya) an average molecular weight between 4000 and 8000 daltons;b) a nitrogen content between 2.4 and 3.0%;c) a sulphur content between 7.5 and 9.5%;d) a sodium content between 9 and 11%;e) a dermatan sulphate content between 5 and 25%;f) a chondroitin sulphate content less than 9%;g) an anti-Xa activity between 11 and 20 .mu./mg; andh) an antithrombin III dependent antithrombin activity of less than 1 .mu./mg.

Abstract: A new anti-thromboticum based on a mixture of oligo- and polysaccharides is provided. The invention also relates to methods for preparation thereof and to pharmaceutical compositions including the said anti-thromboticum.The new product is of natural origin and can be obtained from mammal tissue, particularly intestinal mucous. The product is useful because of its high "benefit/risk" ratio (i.e. the ratio between the anti-thrombotic activity and the haemorrhagic activity).