Methods and Devices for Delivering Drugs Using Drug-Delivery or Drug-Coated Guidewires

Abstract

The present invention relates to a method of delivering drugs having e.g., anti-proliferative activity in the vascular, preferably, the cardiovascular, system locally or systematically using an at least partially drug-coated guidewire. The drug-coated guidewire, particularly an expansion member or portion thereof, is brought into contact with the target tissue or in circulation and the drugs are quickly released into the area surrounding the device in a short time after the contact step. Once the therapeutic drugs are released, they are quickly and effectively absorbed by the surrounding cells or circulation.

Description

FIELD OF THE INVENTION[0001]The present invention relates to the field of medicinal devices and their use in delivering drugs or agents (including biological substances such as cells) to a particular tissue or body lumen for local or systemic effect. In general, the present invention relates to percutaneous transluminal devices and to methods for treating obstructed (sclerotic) vessel lumina in humans. In particular, this invention relates to a low profile guidewire drug delivery apparatus and methods for using a guidewire having an expansion member on which there is disposed a therapeutic agent. In one aspect the present invention dilates an obstruction within a vessel while simultaneously or subsequently delivering a specified therapeutic agent or medicament dose to or adjacent to the dilatation site.BACKGROUND OF THE INVENTION[0002]It has become increasingly common to treat a variety of medical conditions by introducing an implantable medical device partly or completely into the ...

AI Technical Summary

Benefits of technology

[0015]A method of the present invention comprises contacting the tissue or circulation with a radially-expanding guidewire portion, member, or segment which is coated with a therapeutic drug, agent or biological substance, wherein the agent is released into the circulation or deposited onto the tissues surrounding the device in a short time after the contact (or immediately). The therapeutic agent is then quickly, effectively and efficiently absorbed or taken into the tissue, cells or into circulation. The clear and unambiguous, critically important advantage of the guidewire-based approach taken here relative to other endoluminal or endovascular drug delivery approaches is that use of a guidewire expansion member according to this invention provides a minimal diameter “low profile” therapeutic delivery. In practice of this invention precious radial intraluminal or intravascular space or “real estate” (as it is sometimes called) is not occupied with structures such as balloon layers, catheter bodies, sheaths, and other device structural features. In short, the method / delivery of this invention permits access to smaller, more tightly circuitous luminal structures, e.g., of smaller or more highly occluded vessels. It also permits drug delivery without ischemic / schemic effects such as those caused by, for example, vessel blockage with a balloon.

Problems solved by technology

Diseased and obstructed coronary arteries can restrict the flow of blood to the heart and cause tissue ischemia and necrosis.

Open heart surgery is, of course, very traumatic for patients.

Exposure, however, to a medical device which is implanted or inserted into the body of a patient can cause the body tissue to exhibit adverse physiological reactions.

For instance, the insertion or implantation of certain catheters or stents can lead to the formation of emboli or clots in blood vessels.

Similarly, the implantation of urinary catheters can cause infections, particularly in the urinary tract.

Other adverse reactions to implanted or temporary treatment whether introduced by an operation or by a minimally invasive technique, include cell proliferation which can lead to hyperplasia, occlusion of blood vessels, platelet aggregation, rejection of artificial organs, calcification, and impairment of device function.

For example, when a medical device is introduced into and manipulated through the vascular system, the blood vessel walls can be disturbed or injured.

Additionally, if the medical device is left within the patient for an extended period of time, thrombus may form on the device itself with subsequent cell proliferation, again causing restenosis.

As a result, the patient is placed at risk of a variety of complications, including heart attack or other ischemic disease, pulmonary embolism, and stroke.

Thus, the use of such a medical device can entail the risk of precisely the problems that its use was intended to ameliorate.

The risk of thrombosis is the greatest immediately after angioplasty, because the resultant tissue trauma tends to trigger blood clotting.

Indeed, prior art therapeutic methods generally include slow controlled agent release.

Only limited quantities of therapeutic agents can be delivered because of “wash-out” of the drug into the circulation during balloon placement and due to the limited time the inflated balloon can be left in place due to ischemia caused by the balloon.

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