Stent coatings containing HMG-CoA reductase inhibitors

Abstract

Stents with coatings comprising a combination of a restenosis inhibitor comprising an HMG-CoA reductase inhibitor and a carrier. Also provided are methods of coating stents with a combination of an HMG-CoA reductase inhibitor and a carrier. A preferred example of a restenosis inhibitor is cerivastatin. The stent coatings have been shown to release restenosis inhibitors in their active forms.

Description

[0001] 1. Field of the Invention[0002] The present invention generally relates to stent coatings that include bioactive compounds that inhibit restenosis.[0003] 2. Description of the Related Art[0004] Stents are often used in the treatment of atherosclerosis, a disease of the vascular system in which arteries become partially, and sometimes completely, occluded with substances that may include lipids, cholesterol, calcium, and various types of cells, such as smooth muscle cells and platelets. Atherosclerosis is a very common disease that can be fatal, and methods of preventing the accumulation of occluding compounds in arteries are being investigated.[0005] Percutaneous transluminal angioplasty (PTA) is a commonly used procedure to break up and / or remove already formed deposits along arterial walls. PTA can also be used to treat vascular occlusions not associated with atherosclerosis. During PTA, a catheter is threaded through a patient's arteries until the occluded area to be treat...

AI Technical Summary

Benefits of technology

[0030] An artery 10 containing a coated stent 22 prepared according to an embodiment herein is shown in FIG. 2. The stent has a coating 24 containing a polymer and a bioactive compound that inhibits restenosis. By using a stent having this coating 24, the tears 16 shown in FIG. 1 in the endothelium 12 may be reduced or eliminated. Additionally, the mass 18 created by a proliferation of smooth muscle cells 14, as shown in FIG. 1, is eliminated or substantially reduced.

[0052] Cerivastatin has other properties, in addition to its ability to inhibit the proliferation of smooth muscle cells that can contribute to restenosis, making it a desirable component of stent coatings. For example, cerivastatin has anti-thrombotic activity. Stents can often be sites of thrombus formation in the body because of the immunologically-triggered aggregation of different cell types and blood components at the site of a foreign object in the body. Thus, including cerivastatin in a stent coating may help prevent thrombus formation at the site of the stent. Cerivastatin also promotes endothelialization, or the repair of the endothelium 12 after it is damaged, such as by the delivery and expansion of the stent in an artery or other body lumen. It is contemplated that the endothelialization triggered by cerivastatin can help repair the endothelium, and thus reduce tears in the endothelium through which smooth muscle cells and other cell types can migrate into the arterial lumen and proliferate, leading to restenosis.

Problems solved by technology

However, there is a risk that the artery may re-close within a period of from one day to approximately six months of the procedure.

A problem with known biodegradable and biostable stent coatings is that both types of coatings are susceptible to breaking and cracking during the temperature changes and expansion / contraction cycles experienced during stent formation and use.

Stents located within any lumen in the body may not always prevent partial or complete restenosis.

In particular, stents do not always prevent the re-narrowing of an artery following PTA.

However, delivering drugs in this manner may result in undesirable side effects in other areas of the body unrelated to the vascular occlusion.

Also, the administered dose of a drug that is delivered systemically is less effective in achieving the desired effect in the local area of the body in which it is needed.

For example, an anti-restenosis drug delivered systemically may be sequestered or metabolized by other parts of the body, resulting in only a small amount of the drug reaching the local area in which it is needed.

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