Even 150 years after it was identified, multiple sclerosis remains somewhat of a mystery, with researchers still unclear what triggers it, why there are so many forms of the disease, and what is the best way to treat and prevent it.
There are several medications currently available to treat the disease, but most aim only to slow its progression, not halt it, and all are considered only modestly effective. And while there are several drug options for the most common form of MS -- relapsing-remitting MS -- there are no approved treatments for primary progressive MS and only one for secondary progressive MS.
But many MS specialists have hope for new treatments still in development. Some are medications already being used to treat other conditions; others are new medications or treatments altogether.
Here’s a look at some of the developments that MS societies are most excited about:
Gene mutation linked to multiple sclerosis
Geneticists at the University of British Columbia have found a direct genetic link to multiple sclerosis, something that was long thought not to exist. It was identified in two Canadian families in which several members have primary progressive MS, a fast-acting form of MS. Seven out of 10 members of those families who carry the mutation on a gene called NR1H3, developed the disease, the researchers reported in the journal, Neuron.
The researchers say with this finding, they can now create animal models to try to mirror the biological processes that cause the disease in humans. As well, those with a family history of MS might soon be able to be screened for the mutation. If they carry it, doctors will be able detect the disease earlier with diagnostic imaging, and start aggressive treatment to delay the onset of symptoms.
Vitamin D deficiency linked to MS
Vitamin D’s link to MS has been under study for some time. Most recently, a large, detailed study published in 2016 found that a woman’s vitamin D deficiency while pregnant could increase the chance of children developing MS. The study, in the journal JAMA Neurology, found that children of mothers who were vitamin D deficient during pregnancy had a 90 per cent higher chance of developing MS in adulthood compared with those of mothers who were not vitamin D deficient.
The link between vitamin D levels and risk of MS suggests that some environmental factors could affect MS risk even before birth. More research into this link is still needed.
Stem cell transplants
Many MS specialists are excited about the possibility of stem cell transplants as a treatment for MS. One recent international study that looked at the long-term outcomes of MS patients who underwent such transplants found that the treatment can be effective at halting the disease in patients about half the time.
The study, published last month in JAMA Neurology, found that five years after 281 patients underwent stem cell transplants, 46 per cent had still not experienced any worsening of symptoms, including 73 per cent of those with relapsing MS and 33 per cent of those with secondary progressive MS.
But the study authors noted that stem cell transplants carry significant risk, since the procedure involves aggressive chemotherapy to tamp down the immune system. Eight deaths occurred among the study group.
Ocrelizumab
Ocrelizumab is a still-unapproved medication called a monoclonal antibody that's similar to Rituximab, a medication already used to treat certain autoimmune diseases. Three studies published earlier this year in the NEJM showed that the experimental drug helped slow progression of relapsing remitting and primary progressive MS.
The studies found that inflammatory lesions in the brain were reduced by 95 per cent compared with those receiving the standard MS treatment of interferon beta 1a. The studies also showed 47 per cent reduction in relapses of symptoms, and up to a 43 per cent reduction in disability, compared to interferon.
The drug, to be sold under the name Ocrevus, is currently in Phase III clinical trials
Siponimod
Siponimod (also known as BAF312) is a tablet being tested as a potential treatment for secondary progressive MS by Novartis Pharmaceuticals. It works by trapping certain types of immune cell (called B and T cells) in the body's lymph nodes and stops them from getting into the brain and spinal cord.
It’s currently being tested in a phase 3 clinical trial called MS EXPAND. Results from that trial were announced at a scientific conference in September 2016. The drug was found to reduce risk of disability progression by 21 per cent compared with placebo in patients with secondary progressive MS. Siponimod also significantly reduced the rate of brain shrinkage and the number of relapses, particularly in people who were taking the higher doses of the drug.
The full results of this study have yet to be published.
Ibudilast
This drug also known as MN-166, is currently used to treat asthma as well as stroke in some countries because of its anti-inflammatory effects. In 2016, it was approved for "fast track" development by the U.S. FDA, as a potential treatment for primary progressive (PPMS) and secondary progressive MS.
The drug could help protect against cell death, which may help reduce reducing nerve cell loss in MS. One phase II trial showed that ibudilast could help prevent lesions from turning into “black holes” in which nerve cells have been damaged beyond repair. Research is ongoing.
