Patent ID: 11925728
Assignee: SHANDONG HUAAN BIOTECHNOLOGY CO., LTD.
Field: Medical technology (Instruments)
Classification: CPC A | IPC A

Claim 5:
6. A degradable vascular stent capable of avoiding late restenosis, comprising:
a base region formed by a polylactic acid based polymer; at least one storage region in which an active agent is stored; and
an outer layer of a drug sustained release coating covered on the base region and/or the storage region;
wherein before the mass of the polylactic acid based polymer of the base region is decreased by 10-20%, the active agent in the storage region is retained in structural units of the polylactic acid based polymer;
wherein after the mass of the polylactic acid based polymer of the base region is decreased by 10-20%, the active agent in the storage region is released from the storage region;
wherein the storage region is formed of a mixture of an alkaline salt dispersed in a polylactic acid based polymer; and
wherein after the mass of the polymer of the base region is decreased by 10-20%, the alkaline salt is hydrolyzed to release alkaline monomers.