Stem Cells Reduce Pain from Knee Osteoarthritis

By Pat Anson, PNN Editor

A small new study has demonstrated that stem cells collected from a patient’s own bone marrow can significantly reduce pain caused by osteoarthritis of the knee.

In the first clinical trial of its kind in Canada, researchers collected mesenchymal stromal cells (MSCs) from the spines of 12 middle-aged patients with moderate to severe knee osteoarthritis. These “autologous” cells – stem cells derived from a patient’s own fat or bone tissue – were then processed and injected back into the patients’ knees at different doses.

Researchers then followed the patients for the next 12 months, using MRI imaging, biomarkers, molecular fingerprinting and the patient's own assessment of how they felt.

"Our goal was to test for safety as well as to gain a better understanding of MSC dosing, mechanisms of action and donor selection," said lead author Sowmya Viswanathan, PhD, Arthritis Program at the Krembil Research Institute, University Health Network in Toronto.

At the end of the study period, researchers said there were significant improvements in all 12 patients’ pain levels, stiffness and quality of life. The study also showed that the MSCs were safe at all the doses tested and that the higher the dose, the more effective the outcome.

"We also obtained novel insights into a potential anti-inflammatory mechanism of action of these cells in osteoarthritic knee joints. We noted that donor heterogeneity is an important factor, and our assembled panel of genes helps us identify cells which are potent in osteoarthritis. These are important findings which we hope to translate into a larger, powered clinical trial as part of our next steps," said Viswanathan, who reported the findings in the journal Stem Cells Translational Medicine.

Over 250 million people worldwide suffer from knee osteoarthritis (OA), which causes thinning of cartilage and progressive joint damage. Nearly 40 percent of Americans over the age of 45 have some degree of knee OA.

Knee replacement and arthroscopic knee surgeries are commonly used to treat knee OA, even though many studies show they have limited effectiveness. A 2017 study in The British Medical Journal  of over 7,400 patients who had knee replacement surgery found the procedure often had minimal effects on quality of life and wasn’t worth the cost.

Arthroscopic surgery is less invasive than a total knee replacement, but studies also show it is often not effective. In 2017, an international panel of experts reviewed 25 studies involving nearly two million patients and concluded that arthroscopic surgery does not improve long term pain or function in patients with knee conditions such as osteoarthritis.

Because these conventional treatments often fail, there is growing interest in the use of stem cells to treat knee problems. The FDA, however, takes a dim view of autologous stem cells and released guidance in 2017 that requires the cells to undergo “minimal manipulation.”

The FDA recently sent letters to 20 stem cell manufacturers and clinics warning them they were violating FDA regulations. The agency says the science behind autologous cells is still in its early stages and they have not been proven to be safe and effective.

“There’s a false premise being asserted by some in the field that a product derived from a person’s own body and then manipulated and reinserted for another use different from the one it played in its original location is not subject to FDA regulation just because it originated from the person it was given back to,” then FDA commissioner Scott Gottlieb, MD, and Biologics Center Director Peter Marks, MD, said in a statement.

“We’ve seen too many cases of sponsors claiming that cells aren’t subject to FDA regulation just because the cells originated from the same patient to whom the eventual manufactured product is being given. And we’ve seen too many cases of companies making unsubstantiated claims that these treatments prevent, treat, cure or mitigate disease where the products have sometimes led to serious patient harm.”