Q: you also mentioned that low molecular weight heparin is derived from common heparin. Could you please explain the generality and difference of low molecular weight heparin in clinical application?

　　A: although all low molecular weight heparin is produced by the degradation of ordinary heparin, different parent heparins can separate different low molecular weight heparin and affect the composition of the final low molecular weight heparin. Moreover, different production processes can depolymerize common heparin to obtain unique internal and external terminal base structures. Kexai ® is a low molecular weight heparin sodium salt prepared by alkaline degradation of heparin phenyl methyl ester from pig intestinal mucosa. Its chemical structure is unique among currently approved low molecular weight heparins, characterized by a unique polysaccharide sequence and a structural modification known as "fingerprinting," which is highly sensitive to production processes. Now, with advances in analytical technology, it is possible to rediscover these fingerprints, and the special manufacturing process that makes enoxaparin so unique that it cannot be copied. This conclusion has been unequivocally affirmed by the authorities and guidelines. The SFDA's decision to change the generic name of kexel from "low molecular weight heparin sodium" to "enoxaparin sodium" also highlights the differences between low molecular weight heparin from another aspect and cannot be generalized.