Balloon catheter providing decreased irritation and improved drug release and drug penetration

A drug-delivering medical device for delivering agents to treat a target site via a blood vessel, comprising:

• a balloon catheter;
• and
• an inflatable balloon positioned on the balloon catheter,
• the inflatable balloon having a hydrophilic surface,
• at least one portion of the hydrophilic surface being coated with a plurality of nano-carriers, including:
• a first set of nano-carriers comprising a pro-healing agent,
• a second set of nano-carriers comprising an anti-proliferative agent, and a third set of nano-carriers comprising one or both of an anti-inflammatory agent and an anti-thrombogenic agent,
• the first set of nano-carriers having a first average diameter ranging from 800 nm to 1500 nm suitable for penetrating an intima layer of a blood vessel through inter-tissue pores present in the intima layer,
• the second set of nano-carriers having a second average diameter ranging from 300 nm to 800 nm suitable for penetrating a media layer of the blood vessel through a vasa vasorum associated with the media layer and the inter-tissue pores present in the intima layer, and
• the third set of nano-carriers having a third diameter ranging from 10 nm to 300 nm suitable for penetrating an adventitia layer of the blood vessel through the inter-tissue pores present in the intima layer, the vasa vasorum associated with the media layer and a vasa vasorum associated with the adventitia layer;
• wherein a first time required for the third set of nano-carriers to release from the hydrophilic surface upon coming in proximity of the target site is less than a second time required for the second set of nano-carriers and the first set of nano-carriers to release from the hydrophilic surface;
• wherein the third set of nano-carriers exhibit a rapid rate of release from the hydrophilic surface and wherein the second set of nano-carriers and the first set of nano-carriers exhibit slower rates of release from the hydrophilic surface as compared with the rate of release of the third set of nano-carriers;
• at least one adjacent portion of the hydrophilic surface being uncoated and exposable to a blood or a tissue environment for rapid dissolution from the inflatable balloon and for rapid dissolution from underneath the nano-carriers of an adjacent coated portion of the hydrophilic surface, the rapid dissolution from underneath providing an increase in the rapidity of release of the nano-carriers of the adjacent coated portion;
• each nano-carrier of the plurality of nano-carriers comprising a respective agent surrounded by an encapsulating medium,
• wherein a surface of each nano-carrier is devoid of the respective agent and 30% to 80% of the plurality of the nano-carriers are released from the hydrophilic surface within 15-90 seconds when the inflatable balloon is inflated upon coming in proximity to the target site in the blood vessel;
• and
• wherein the third set of nano-carriers penetrating into the adventitia layer remain in the adventitia layer for a prolonged time and act as a reservoir of the one or both of the anti-inflammatory agent and the anti-thrombogenic agent to slowly release the one or both of the anti-inflammatory agent and the anti-thrombogenic over the prolonged time.