Professor receives grant to study localized, high-intensity drug delivery for treatment of vascular restenosis

The National Heart, Lung, and Blood Institute of the National Institutes of Health has awarded Bryan Tillman, MD, PhD, associate professor of Surgery in the Division of Vascular Surgery at The Ohio State University College of Medicine, his second R01 grant. The grant will help to fund a study of a stent, developed with co-investigator Saami Yazdani, PhD, associate professor of Engineering at Wake Forest University, that can prevent restenosis, a condition that causes scar tissue to form and block blood vessels after vascular interventions.   

More than 250,000 angioplasties, stents and open bypasses are performed each year to open occluded vessels for preservation of life and limb. Yet, more than half of them will fail in less than five years due to restenosis.  

“I will use this four-year, $2.7 million grant to study the use of a retractable drug infusion stent that is designed to be removable and preserve blood flow while delivering drugs effectively,” Dr. Tillman says. “And to examine more effective drug delivery to specific regions, including the vascular wall or vascular beds.”   

The study, titled A Retrievable, Chambered Stentgraft to Achieve Localized, High Intensity Drug Delivery for Treatment of Vascular Restenosis, aims to improve patient outcomes while reducing complications in a variety of medical conditions, such as chemotherapy, vasoactive agents, gene vectors and immunomodulatory agents.

Innovative stent design

The stent intends to offer more effective therapies for restenosis and other conditions, with the potential to reduce drug loss in the bloodstream and improve medication exposure time. The existing drug-coated balloon procedure has limitations because it can only be used for a brief period, as it restricts blood flow, and drugs wash off the balloon. This novel stent intends to infuse any type of liquid drug that’s currently not possible with a drug-infused balloon or permanent stent approach.   

“The ability to open blocked veins and arteries as well as to prevent the scar tissue that forms after surgeons perform procedures that go in through the veins is key,” Dr. Tillman says. “This could improve the treatment of recurrent vascular narrowing.” 

Broader implications

Dr. Tillman also recently received a Transformational Project Award from the American Heart Association to use a novel drug-delivery stent graft he developed at The Ohio State University Wexner Medical Center. This study investigates how inflammation contributes to aneurysm development. Aneurysms are a leading cause of death in the United States, and the scientific community hasn’t developed a strong understanding of the mechanisms behind aneurysm growth and rupture.  

That is why this innovative work that has the potential to reduce drug loss in the bloodstream could usher in the use of higher dose medications and improve exposure time.  Ultimately this may offer medical treatments to halt aneurysm growth and rupture.  

“Our goal is to offer more effective therapy for restenosis and – more broadly – new approaches for focused drug delivery in treating a variety of other conditions,” Dr. Tillman says.