Mesenchymal Stem Cells in the Treatment of ALS

Amyotrophic lateral sclerosis or ALS is a neurological disease that causes muscle weakness, profound disability, and ultimately death. ALS is sometimes referred to as Lou Gehrig’s disease, named for the New York Yankee baseball player who developed the condition later in his life. Notably, physicist Stephen Hawking long suffered from the condition.

ALS affects the nerves that control movement. As nerve cells become dysfunctional and die, a person’s muscles become weak. The disease often starts with weakness in one part of the body before moving to other parts. In 4 out of 5 people with ALS, the first symptom is a weakness of one limb but not the other. Over time, however, the disease spreads to virtually all motor neurons (nerve cells) in the body. Eventually, patients are unable to walk because of muscle weakness and are usually confined to a wheelchair. The condition becomes particularly difficult to manage and potentially life-threatening when it starts to affect lung muscles, which make it hard for patients with ALS to breathe.

There is no cure for amyotrophic lateral sclerosis. For the most part, however, treatment for ALS focuses on reducing the symptoms of the condition rather than treating it. Patients often undergo intensive physical, occupational, and speech therapy regimens to help manage symptoms of ALS. Physicians may prescribe drugs to reduce muscle spasms, sleep problems, and pain associated with the condition. Researchers are constantly looking for ways to improve ALS treatment.

Dr. Petrou and co-authors recently reported clinical trial results in the highly regarded medical journal, JAMA Neurology. The researchers started their research by altering mesenchymal stem cells in the laboratory so that they produce neurotrophic growth factors. In other words, they engineered stem cells to release substances that help nerve cells grow and survive. Then they tested these stem cells in two clinical trials. In the first clinical trial, the doctors used these stem cells to treat six patients with early-stage ALS and six patients with advanced ALS. In the second clinical trial, they tested the stem cells in 14 patients with early-stage ALS.

All patients in both trials tolerated the stem cell treatments very well. There were no serious side effects related to treatment. 87% of the patients responded positively to treatment, which means they showed at least 25% improvement in physical function and/or lung function. These positive results from stem cell treatment are particularly impressive because ALS gets worse over time. Patients generally either stay the same or get worse—it is quite unusual for them to get better. Encouraged by these results, the researchers who worked on this study will now confirm these results in larger clinical trials. The hope is that this stem cell treatment will be available for patients with ALS in the coming years.

Reference: Petrou P. et al. (2016).Safety and Clinical Effects of Mesenchymal Stem Cells Secreting Neurotrophic Factor Transplantation in Patients With Amyotrophic Lateral Sclerosis: Results of Phase 1/2 and 2a Clinical Trials. JAMA Neurology.2016 Mar;73(3):337-44.