Stem Cells for Stroke Recovery
A phase II trial shows the safety of multipotent progenitor cells in stroke victims – but what about efficacy?
“We lack effective therapies for stroke,” says David Hess, Professor and Chairman of the department of neurology at Augusta University. Hess believes the answer lies with stem cell therapy – and, to that end, a recent paper shares the results of a phase II trial of multipotent adult progenitor stem cells in ischemic stroke patients (1). Although the findings showed that the treatment was safe over a 90-day period, there was no significant improvement versus a placebo. Despite the results, the team remain hopeful. We spoke with Hess to find out why.
Why focus on progenitor cells?
I believe cell therapy is the third wave of therapeutics – after small molecules and biologicals. As there was some evidence that cell therapy was effective against myocardial infarction in the heart, we thought it could be effective against stroke in the brain. Other than tissue plasminogen activator and mechanical thrombectomy – a very effective device-based therapy – there are few efficacious treatment options.
Can you share more details of the trial?
The cells were very safe and well tolerated – which was initially a hurdle we had to overcome – and there was a trend to improved outcomes and reduced infections, especially in patients treated less than 36 hours after their stroke. In keeping with their immunomodulatory effect, the cells reduce the acute neuroinflammatory response that increases tissue injury after stroke, and prevent splenic and immune exhaustion – all of which fit our overall hypothesis; unfortunately, we expanded the time window to 48 hours, so we had many patients treated late. We believe this may have blunted the effect.
What’s next?
Hints from the phase II trial suggest that treating patients under 36 hours will indeed lead to better functional outcomes at three and 12 months. But before these cells could ever be approved for routine human use, we will need to demonstrate their safety and efficacy, which we plan to do in two late-phase trials – one taking place in Japan and the other taking place in North America and Europe.
- DC Hess et al., “Safety and efficacy of multipotent adult progenitor cells in acute ischaemic stroke (MASTERS): a randomised, double-blind, placebo-controlled, phase 2 trial”, Lancet Neurol, [Epub ahead of print] (2017). PMID: 28320635.
My fascination with science, gaming, and writing led to my studying biology at university, while simultaneously working as an online games journalist. After university, I travelled across Europe, working on a novel and developing a game, before finding my way to Texere. As Associate Editor, I’m evolving my loves of science and writing, while continuing to pursue my passion for gaming and creative writing in a personal capacity.