Magnetically targeted delivery of therapeutic agents to injured blood vessels for prevention of in-stent restenosis.

Magnetic guidance is a physical targeting strategy with the potential to improve the safety and efficacy of a variety of therapeutic agents--including small-molecule pharmaceuticals, proteins, gene vectors, and cells--by enabling their site-specific delivery. The application of magnetic targeting for in-stent restenosis can address the need for safer and more efficient treatment strategies. However, its translation to humans may not be possible without revising the traditional magnetic targeting scheme, which is limited by its inability to selectively guide therapeutic agents to deep localized targets. An alternative two-source strategy can be realized through the use of uniform, deep-penetrating magnetic fields in conjunction with vascular stents included as part of the magnetic setup and the platform for targeted delivery to injured arteries. Studies showing the feasibility of this novel targeting strategy in in-stent restenosis models and considerations in the design of carrier formulations for magnetically guided antirestenotic therapy are discussed in this review.