August 29, 2017
Small study shows that treatment with an anti-oxidant slows brain tissue loss in individuals with secondary progressive MS
Antioxidants are substances that are man-made or naturally found in food and are taken to prevent or delay damage to cells in the body. LipoicAcid (LA) is an over the counter antioxidant supplement which has been recently shown to reduce inflammation and disability in mice that have an MS-like disease. To build on these findings, Dr. Rebecca Spain and her colleagues at Oregon Health & Science University in Portland, Oregon, examined if LA can reduce the rate of atrophy or brain loss in individuals with secondary progressive MS. Atrophy is considered an important outcome in progressive MS clinical trials, as it is correlated with the level of damage that has occurred as a result of the disease. The results of the pilot clinical trial were published in the Neuroimmunology and Neuroinflammation journal.
In a single-site, phase II, double-blind clinical trial, researchers randomly assigned 51 individuals to orally receive either LA (1200 mg) or placebo daily for two years. The primary outcome measure was the percentage of brain volume loss as determined by MRI. The team also looked at changes in disability and safety of LA.
The results showed that participants who received LA had a 68% decrease in the amount of brain volume loss compared to individuals on placebo. While individuals treated with LA showed slight improvements in the time taken to walk 25 feet compared to the placebo group, these finding were not statistically significant. Furthermore, participants who were given LA fell down fewer times than individuals who were given placebo.
In terms of safety, there was a greater occurrence of stomach upset in the LA group versus the placebo group, as well as occurrence of vomiting, dehydration and skin rash. There was one case of kidney failure and one case of kidney inflammation in the LA treated group.
Overall, this study achieved its primary endpoint of slowing brain volume loss following LA treatment. The researchers noted that the reduction in brain volume loss they observed is comparable with trials involving the drug ocrelizumab, which is being reviewed by Health Canada for primary progressive MS. However, the ocrelizumab clinical trials were much larger, therefore additional clinical trials of LA in individuals with progressive MS are needed to confirm its efficacy. The dose of LA that is currently being investigated in clinical trials for treatment of SPMS is 1200 mg/day, which is double the Health Canada maximum recommended daily intake of 600 mg/day. Thus larger trials will be critical to providing more insight into the safety of higher doses of LA. Nevertheless, these results are encouraging in that they illustrate the benefits of repurposing existing drugs to offer viable treatment options for people with progressive MS as early as possible.
Spain R et al. (2017) Lipoic acid in secondary progressive MS. Neurol Neuroimmunol Neuroinflamm. 4(5): e374.