Inside the Ireland facility revolutionizing the way stroke care is approached

About 15 years ago, Michael Gilvarry and the team had a eureka moment.

Gilvarry, now Head of R&D and General Manager at Johnson &Johnson MedTech Neurovascular Galway, and his colleagues were working on devices for thrombectomy, a treatment for stroke in which blood clots are mechanically removed using fine catheters, clot-capturing devices and suction. At the time, thrombectomy was rapidly being adopted becoming a standard treatment for acute ischemic stroke, and medical device companies raced to develop products to help physicians perform the lifesaving procedure.

But there was a problem with how those device-makers were approaching the task, Gilvarry realized. And the problem was fundamental.

From Gilvarry’s point of view, many were designing their thrombectomy portfolio without a sophisticated, thorough understanding of the physical makeup of the blood clots that those products were intended to remove.

“We were designing devices without knowing what the clots were composed of,” Gilvarry says. The prevailing thought at the time was that a clot was a clot; all were essentially the same.

But as thrombectomy became more widely used—and physicians began seeing the clots they were removing, up close—they realized that wasn’t the case at all. Clots causing ischemic stroke are heterogeneous in composition and mechanical properties. Newer blood clots, scientists observed, were bright red and gel-like. But more mature clots could be harder or more fibrous, and often lighter in color. They could also take various shapes—sometimes globular, sometimes long and string-like. Calcified, stiff clots and clots resistant to pulling, for example, could all present special challenges for physicians during thrombectomy.

Researchers began to realize they needed to prioritize the study of stroke-causing clots before they could design and produce the best possible products for their removal. “We’d been putting the design before the science,” Gilvarry says. “We needed to put the science first.”

That’s partly why, in 2014, Johnson & Johnson MedTech launched NTI, its scientific research arm, which is led by an interdisciplinary team of scientists and engineers who collaborate with researchers and clinicians in and outside of Johnson & Johnson. 

Located at a state-of-the-art research facility in Galway, Johnson & Johnson Ireland, “we sit at the intersection of clinical research, academic research and our own internal research and development team,” says Ray McCarthy, R&D Director, NTI Research Lead, J&J MedTech Neurovascular. “Our job is to translate clinical patient needs and academic research into something our development team can innovate around.”

One of the NTI’s founding flagship endeavors has been to study the very problem that interested Gilvarry—blood clots, the cause of stroke—as it had never been studied before. At the facility, Gilvarry, McCarthy and their colleagues are collaborating with physicians from across the world to collect clots retrieved from patients in a clinical setting during thrombectomy, so that they can be banked and systematically analyzed by Johnson & Johnson and other scientists.

Learning about the complex nature of blood clots unlocked additional research pathways for the NTI team. As their understanding developed, NTI scientists figured out how to produce clots that mimicked real ones. Those clot replicas could then be used in simulations of real-life stroke scenarios, which engineers could employ to gain insights into how well their device prototypes were working and how to refine and improve them.

“There’s still a lot we don’t know about the disease, and we're learning as we go,” says Gilvarry. “I think what sets the NTI apart is the approach that we take to understanding the science of these problems before we develop devices for treating them.”

Recognizing the innovative work of the NTI, Johnson & Johnson MedTech deepened its support for the Galway group, announcing in 2022 a €50 million investment into Neurovascular R&D. And the research underway is critical because globally, stroke is the second leading cause of death, and one in four people above age 25 will experience one in their lifetime.

According to McCarthy, since 2022 that investment has been used to attract the brightest minds in the field, advance the facility’s prototype manufacturing capabilities, and broaden the NTI’s research focus to include other neurovascular diseases.

One such challenge is chronic subdural hematoma (cSDH), a condition in which blood slowly collects between the skull and the brain’s surface, often after a head injury. Small, stable cSDHs may be managed conservatively with clinical monitoring and repeat imaging because spontaneous reabsorption can occur. Hematomas that produce significant mass effect or cause progressive neurological deterioration are generally considered for more timely intervention.

In recent years, scientists have been developing a minimally invasive treatment for cSDH that uses a glue-like liquid to block the small blood vessels feeding the hematoma, with the goal of reducing its growth and the chance it will recur.

In the United States, the liquid embolic agent has been used as a safe and effective option for treating cerebral arteriovenous malformation (AVM), a tangle of blood vessels in the brain that disrupt normal blood flow. In some cases, a physician will perform embolization before surgery to reduce blood flow to the lesion and lower the risk of intraoperative bleeding.

Now, NTI researchers are evaluating its use for chronic SDH. Among its potential benefits are that it can act relatively quickly and be delivered through a minimally invasive catheter. When injected into a small artery that feeds the hematoma, the liquid embolic occludes that vessel, reducing blood supply to the hematoma’s membrane. “It’s very straightforward and simple to use,” Emmanouil Kasotakis, Principal Polymer Chemist, Neurovascular & General, Johnson & Johnson MedTech, “and importantly, it has a strong safety record and efficacy across approved indications.”

In its current formulation, the solution must be mixed by the physician before administration. Kasotakis and his team are developing anatomically accurate, real world benchtop models to study how TRUFILL n-BCA is delivered to the middle meningeal artery (MMA).

“The team’s contributions are giving physicians more and better tools to help patients with cSDH,” Gilvarry says. 

“Treating cSDH with liquid embolics is a newer area of research,” says Gilvarry. “We’re approaching it as we do all of our research: by understanding the anatomy of the microcirculation within the brain, replicating that in simulation models and testing variables within those simulations.” 

Going forward, the NTI team plans to leverage the same approach to investigate a host of other neurovascular conditions, which may include hydrocephalus, a buildup of cerebrospinal fluid on the brain, and aneurysm, which occurs when a blood vessel in the brain bursts.

“We’re at the tip of the iceberg in terms of what we can do with our capabilities," McCarthy says. 

Johnson & Johnson’s emphasis on building strong relationships with clinical research partners makes the work all the more rewarding, he adds. “We’re all engineers and scientists who got into this work because we’re interested in solving problems, just like physicians,” McCarthy says. “We all want to come up with better ways of treating patients.” 

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