Implantable drug delivery catheter system with capillary interface

A drug delivery system for delivering drugs to a location under a mammal's skin, the drug delivery system comprising:

• a drug feed device including a drug supply and a pump, the pump adapted to produce a positive pressure flow of drugs out of the drug supply;
• a catheter having at least one lumen in fluid communication with the feed device for receiving a flow of drugs, a portion of the catheter adapted disposed under the skin of a mammal;
• a drug delivery device adapted to be mounted under the skin of a mammal, the drug delivery device including:
• a support structure forming a drug reservoir, the support structure having a drug port on it which is attached to the catheter and provides fluid communication between the lumen in the catheter and the drug reservoir, the support structure having openings which permit drugs to flow out from the drug reservoir and into the mammal;
• and
• a capillary interface disposed about the support structure, the capillary interface including an outer membrane pore structure which is adapted to facilitate the ingrowth of vascular tissue, and an inner membrane pore structure which is adapted to inhibit the ingrowth of vascular tissue while permitting the flow of drugs from the support structure out through the capillary interface, the outer and inner membrane pore structures including a plurality of pores, the pores on the outer membrane pore structure being substantially aligned with the pores on the inner membrane pore structure.

A non-permanent drug delivery catheter system for implantation across the skin of a mammal, adapted to promote growth of highly vascular tissue immediately adjacent to a drug delivery lumen without formation of a fibrous tissue capsule, the system providing rapid and controlled drug absorption kinetics targeted to the subcutaneous tissues, the drug delivery system comprising:

• a flexible drug delivery catheter external to the body, with a drug delivery lumen, and a proximal connector for attachment to an insulin pump or syringe,
• a base platform for attachment to the external surface of the skin, adapted with a drug delivery lumen to permit the flow of drug from the lumen of the flexible drug delivery catheter, to the lumen of the support structure reservoir located within the subcutaneous tissues of the body, further adapted with a sharp tipped needle that penetrates a silastic membrane within the base and forms a stylet for percutaneous insertion of the support structure reservoir through the skin,
• a support structure having a plurality of holes to permit the flow of drug into the vascular tissues,
• a small pore inner membrane structure, adapted to adhere to the underlying support structure, the membrane structure having a pore size, thickness, and chemical composition to provide a controlled rate of outward drug diffusion, said inner membrane structure adapted to maintain an open pore structure by inhibiting adhesion and ingrowth of cells and extra cellular components, thereby permitting controlled and directional flow of drug from the support structure into the vascular tissue;
• and
• an outer membrane with a larger interconnecting pore structure, adapted to adhere to and interconnect with the pore structure of the inner membrane and adapted to optimize ingrowth of vascular tissue immediately adjacent to the small pores of the inner membrane, thereby permitting drug to flow from the support structure reservoir, through the inner membrane, to the immediately adjacent vascular tissue.

A non-permanent drug delivery catheter system for implantation across the skin of a mammal, adapted to promote the growth of highly vascular tissue immediately adjacent to a drug delivery lumen without the formation of a fibrous tissue capsule, the system providing rapid and controlled drug absorption kinetics targeted to subcutaneous tissues, the drug delivery system comprising:

• a flexible drug delivery catheter with a drug delivery lumen, a portion located external and a portion located internal to the body of a mammal and, said flexible drug delivery catheter having a proximal connector for attachment to an insulin pump or syringe;
• a support structure located internal to the body of said mammal, said support stucture having a plurality of holes to permit the flow of drug into the vascular tissues,
• a small pore inner membrane structure, adapted to adhere to the underlying support structure, the membrane structure having a pore size, thickness, and chemical composition to provide a controlled rate of outward drug diffusion, said inner membrane structure adapted to maintain an open pore structure by inhibiting adhesion and ingrowth of cells and extracellular components, thereby permitting controlled and directional flow of drug from the support structure into the vascular tissue;
• and
• an outer membrane with a larger interconnecting pore structure, adapted to adhere to and interconnect with the pore structure of the inner membrane and adapted to optimize ingrowth of vascular tissue immediately adjacent to the small pores of the inner membrane, thereby permitting drug to flow from the support structure reservoir, through the inner membrane, to the immediately adjacent vascular tissue.