Stents and magnetic fields might also deliver combination therapies. Nanoparticles could carry different agents simultaneously or at different times. Since the stents remain in place, physicians could retreat patients, delivering therapeutic agents through catheters under magnetic guidance. Because the magnetic effect concentrates its delivery package at the specific site of a stent, physicians could achieve stronger effects with lower overall doses of a given agent. Contributing to the technique's efficiency, the polymer-based nanoparticles provided sustained drug release over the 14-day course of the study.
Levy envisions a future therapy called vascular magnetic intervention, in which a patient would receive regular treatments from a vascular surgeon or interventional cardiologist who delivers doses of therapeutic nanoparticles under a low-level, uniform magnetic field.
Although currently stents are primarily used for heart patients, Levy cited a great unmet need among the millions of patients with chronic peripheral artery disease. In diabetes patients with poor circulation, for example, drug-eluting stents have had "disappointing results," Levy says, because leg arteries are larger than coronary arteries, and insufficient drug doses are included in the stent coating. "Our technique offers opportunities for a novel approach in which we can vary doses and repeat the treatments," he adds.
In children, stents are used to mechanically enlarge anatomic structures for conditions such as peripheral pulmonary artery stenosis, the heart defect coarctation of the aorta, and atrial septal defects created by interventional techniques to provide oxygenated blood. Levy suggests the magnetically guided nanoparticles might d
|Contact: John Ascenzi|
Children's Hospital of Philadelphia