In the competitive world of health care technology, Sanford Health and six other health care systems hope to provide a minimally invasive option to high-risk vascular disease patients who currently have limited clinical options. They’re doing it through a very noncompetitive approach: working together and sharing what they learn.
The investigational device that prompted the collaboration is the Medtronic Valiant TAAA Stent Graft System. Patrick Kelly, M.D., a vascular surgeon at Sanford Health in Sioux Falls, South Dakota, invented the initial concept for the device. Medtronic, a global leader in medical technology, then licensed the technology from Dr. Kelly to further develop the device.
It is designed to treat a thoracoabdominal aortic aneurysm, or TAAA. That is a complex condition that causes a dangerous bulging of the aorta extending from the chest down into the abdomen. The condition typically involves the branch arteries that supply blood to multiple internal organs. Left untreated, the aneurysm can rupture and cause sudden death.
The standard of care is complex open surgery, which is associated with a high rate of complications and mortality. And 40% of patients are not considered candidates for open surgical repair. Dr. Kelly’s concept has the potential to open the door for more of those people to be treated utilizing a minimally invasive approach.
Sanford Health received U.S. Food and Drug Administration approval in 2014 to run a physician-sponsored investigational device exemption, or PS-IDE. That allows physicians to study the early clinical performance of the device before it is used in a larger patient population. Rather than go it alone, Sanford Health in collaboration with Medtronic has developed a streamlined process that allows more surgeons to test the device and more patients to be treated with it.
The six other health systems taking part: New York University, Massachusetts General Hospital, University of Southern Florida, Vanderbilt University, The Christ Hospital and The Johns Hopkins Hospital.
“We’ve helped bring all of those sites together to have a common database that we’re collecting and analyzing. And we’re also taking our lessons learned from a case in New York and applying it to a case Sioux Falls, for example, and just learning together as we go through it,” said Katie Pohlson, who oversees regulatory issues for Sanford Health’s commercialization team.
The approach isn’t unique, but the results of the collaboration are.
“We’ve just done a good job of establishing this network of independent PS-IDE sites and bringing it further than most people. Most people just focus on one individual site,” she said. “We’ve been able to build a team of cooperative investigators to bring this forward.”
Stent graft testing
The goal is to evaluate the potential to provide patients with TAAA access to a minimally invasive treatment, while also evaluating how the aortic stent graft works in a real-world population.
“We’re consenting patients appropriately, collecting data and periodically looking to make sure we are seeing safety and preliminary signs of efficacy. If there are concerns, that would end the trial or maybe put it on hold and put some more patient protection measures in place. That’s really the purpose of a PS-IDE, is to study a research device in a controlled fashion,” Pohlson said.
The net effect will be to lower the risks of the technology and help determine patient selection for a larger trial, she added. “This way we learn, ‘Who should we be treating with this device? What kind of outcomes can we expect? What should we be looking at when we look at market approval? How should we roll this out?'”
Pohlson presented last year at a conference hosted by the Children’s Hospital of Philadelphia. She shared Sanford Health’s success in establishing these collaborations and how to apply them to other medical specialties.
“We’ve had people reaching out to us asking for our experience and how we’ve navigated obtaining a PS-IDE and the unique structure we’ve established in order to get early feasibility clinical data,” Pohlson said.
“The thing that’s unique with what we’re doing is we’ve really taken this from a physician-modified device and it’s now being further developed by industry. We’ve helped set the stage for running these independent studies and provided these templates to other sites, so they can have the same success we’ve had in running an independent trial and pooling all of that data together in a consistent manner.
“It can be pooled together to get common results that can be compared and analyzed as one cohesive cohort, instead of multiple kind of choppy pieces where maybe one site is collecting one piece of data and another site is collecting it in another way. We’ve really standardized the approach to data collection, patient selection, outcomes that we’re looking at in the study.”
In a house, if a pipe has a hole in it or is clogged, the solution is to reline the pipe. In arteries and veins, an aortic stent graft does the same thing for an aneurysm.
Dr. Kelly said most competing devices all try to mimic the aorta but often don’t fit because the artery is contorted. “The problem with that is we’re trying to fix something abnormal,” he said.
The stent graft system doesn’t look anything like human anatomy because it’s non-anatomical.
“It’s a construct of a metal scaffolding over the top of it,” he said. “My stance has always been, ‘If I try to build a graft that looks like a person’s aorta, then I’m limited by their aorta.'”
Help more people
That design allows physicians to place it in more places that are otherwise hard to fix.
“What becomes challenging is if that dilated segment is in the segment (of an artery or vein) where there are major branches going to the arms or the legs or the kidneys. A great example of this is it’s a lot easier to fix a highway when it’s a straight segment than to fix a highway that has a major intersection,” he said. “We’re not limited by people’s anatomy.”
Hence, many older people who otherwise would not qualify for open surgery may have an improved quality of life and a chance at longer life with an endovascular approach like TAAA.
“It allows us to fix the same type of aneurysm through a couple little poke-holes in the groin and maybe a little incision in the arm,” Dr. Kelly said. “Which means, we have the potential to expand it from only being able to treat people 65, 70 years old to offering it to patients that are in their 70s and 80s that maybe have some other medical problems.”
Dr. Kelly has continued to evolve the device over the years, including developing the second-generation version called the Unitary device. This device is intended for aneurysms that extend up to the branch arteries but don’t fully extend into the chest. It covers less of the aorta and hopefully will reduce the risk of devastating complications such as paraplegia. The Unitary device is currently offered only at Sanford Health as part of the PS-IDE.
The stent graft containing technology licensed by Medtronic received acceptance in 2019 into the FDA’s Breakthrough Devices Program. It’s intended to help patients receive more timely access to breakthrough technologies that have the potential to provide more effective treatment or diagnosis for life-threatening or irreversibly debilitating diseases or conditions.
Dr. Kelly has treated more than 100 patients with both devices, and the early results are promising, Pohlson said.
“We want to know how this impacts other people that we may not see in South Dakota,” she said.
“We are broadening the number of patients involved and providing access to patients across the country. It’s difficult for people that are a little bit older. They may be in poor health, so for them to travel to South Dakota doesn’t really make sense. We’re also expanding the number of users. It’s important to understand how this device works in Dr. Kelly’s hands as the inventor but also in other experienced users’. Is it something that’s reproducible? That’s part of research, is figuring out, ‘Can you reproduce it and get reliable results?'”
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