Stem cells inject hope for future stroke recovery

A promising experimental stem cell treatment from the United States that could help recovery years after a stroke is receiving a lot of media attention. While it’s still in the early stages and needs to go through appropriate clinical trials, it has potential to help stroke patients in the future.

In the study, scientists at Stanford University injected stem cells into the brains of eighteen stroke survivors. Although most of the patients had their strokes at least a year previously, they still gained improvement in motor function after the treatment.

“This wasn’t just, ‘They couldn’t move their thumb, and now they can.’ Patients who were in wheelchairs are walking now,” said neurosurgeon Gary Steinberg, who was the lead researcher.

Cells in the brain and other parts of the human body are specialised and normally aren’t able to take on other roles. But stem cells are different, in that they are able to divide and transform into other specific types of cells. The stem cells used in this experiment came from donor bone marrow, and they are normally used by the body to replace muscle, fat, tendon and bone.

The researchers modified the stem cells to improve their ability to restore brain function, before injecting them into the patients. They then used brain imaging and other tests to see whether the stem cells kicked off ongoing regeneration.

“We know these cells don’t survive for more than a month or so in the brain,” said Professor Steinberg. “Yet we see that patients’ recovery is sustained for greater than one year and, in some cases now, more than two years.”

Because this was an early, small experiment with a handful of patients, more and larger studies are needed to make sure the treatment truly works and to watch out for harmful side effects.

This experiment was a phase 1 clinical trial, which is designed to check whether it’s safe to give patients a treatment that was developed in the laboratory.

Stanford University has now moved on to recruiting 156 stroke survivors for a phase 2 trial, to see whether the results can be replicated in a larger number of patients. A successful phase 2 trial is usually followed by phase 3—which is a rigorous, randomised comparison with standard treatments—before doctors and regulators can be confident that it’s safe and effective enough to use.

Research takes time, and for good reason. However, it is great news that this most recent experiment at least indicated the technique appears good enough to be worth the further study.

“This is an important stem cell research milestone for stroke,” said Professor Simon Koblar, Stroke Foundation Clinical Council Chair and a leading stroke physician from the University of Adelaide.

Professor Koblar and his team are currently planning a similar phase 1 trial of stem cells in Australia. However, instead of bone marrow from an unrelated donor, their experiment will use stem cells extracted from dental pulp in a patient’s own teeth. Professor Koblar and his team hope that those cells will also stimulate recovery in stroke-affected brains.

In the meantime, the Stroke Foundation advises that people considering any changes to their treatment should consult their health professional.

Read more about the Stanford University study at http://med.stanford.edu/news/all-news/2016/06/stem-cells-shown-safe-beneficial-for-chronic-stroke-patients.html.

And for more on the phases of clinical trials, see https://www.australianclinicaltrials.gov.au/what-clinical-trial/phases-clinical-trials.