Multifunctional Medical Device Having Zero-Order Kinetics For Controlled Delivery Of Pharmaceutical Agents

Life Sciences : Drug Delivery

Available for licensing


  • Salomon Stavchansky, Ph.D. , Pharmaceutics
  • Paul Ho, Ph.D. , Mechanical Engineering
  • Phillip Bowman, Ph.D. , Pharmaceutics
  • Ashish Rastogi , Pharmaceutics
  • Zhiquan Luo , Physics

Background/unmet need

A number of implantable drug delivery devices are capable of delivering a drug to the body lumen. These devices deliver the drug locally, improve their efficacy, and decrease side effects when compared to other routes of administration such as oral, renal, topical or systemic. A problem with the current devices is that the delivery rate cannot be controlled beyond a certain point. A popular drug delivery device is a drug-eluting stent, which is used to open up a clogged atherosclerotic coronary artery. The drug helps to prevent re-clogging of the artery. However, the initial release of the drug is very rapid, releasing 20% to 40% of the total drug in a single day. Such high concentrations of the drug lead to cytotoxicity at the targeted site.

Additionally, there is a need for a drug delivery device which can be tailored to deliver any therapeutic, diagnostic, or proplylactic agent for several years at a controlled rate. Hence, the need for repeated dosing of a medication can be eliminated and patient compliance improved. Such a device would also decrease the risk, pain, and expense for patients.

Invention Description

Researchers at The University of Texas at Austin have developed a controlled-release drug delivery device that provides zero-order drug release kinetics. The drug is packaged inside of an impermeable matrix with at least one hole on the surface, which allows the drug to move out of the reservoir at zero order. The UT inventors have laboratory data which displays the controlled release kinetics of the device. Variations in the size, number, and spacing of the holes enables the controlled release of a drug at the target site.

This device is advantageous because it provides local drug delivery, which allows for a decrease in side effects and an increase in drug efficacy. In addition, the novel technology offers zero-order drug release kinetics, is polymer free, and can be utilized to provide long-term activity, lasting for years if necessary. This novel UT Austin technology can be utilized for a variety of implanted drug delivery devices such as for the brain or ear. The device has numerous medical applications, including insulin delivery for management of diabetes, drug-eluting implants for cancer therapy, drug-eluting stents to treat atherosclerosis, pain management applications such as management of lower back pain by implantation into CNS or invertebrae or discs, and much more. As such, millions of patients could benefit from its usage every year around the world.


  • No polymer, and hence no variation in polymer layer coated on the stent surface
  • No dose dumping due to polymer cracks
  • Drug release controlled by hole size, number of holes, diameter of tubes, and distance between adjacent holes
  • Multiple drug applications possible
  • Superior design; less injury
  • Biocompatible materials
  • Drug release is unidirectional.
  • Drug release can range from several hours to several years, depending on the utility.


  • Local drug delivery means fewer side effects, increased efficacy
  • Controlled release of the drug
  • Zero-order drug release kinetics
  • Polymer free
  • Long-term activity

Market potential/applications

Pharmaceutical and biotechnology companies with interest in drug delivery and microtechnology may be interested in this technology.

Development Stage

Proof of concept

IP Status

  • 1 U.S. patent application filed
  • 1 U.S. patent issued: 9,005,649