Experimental SPMS Medication Shows Positive Results

A Phase III study with siponimod, an experimental oral treatment for MS, is showing positive results for individuals with secondary-progressive multiple sclerosis (SPMS). According to an August 25th press release from Novartis, the pharmaceutical company developing siponimod, the Phase III EXPAND study met its primary endpoint, which was to reduce the risk of confirmed disability progression at three months, versus a placebo. This improvement in the time to three-month confirmed disability progression was determined according to measurements on the expanded disability status scale (EDSS).

These study results are significant because no disease-modifying therapy is available in the United States for the long-term treatment of SPMS. This form of MS follows relapsing-remitting MS (RRMS) and is characterized by a slow and steady progression, with or without relapses. If relapses do occur, they usually do not fully remit.

Novartis states that the EXPAND trial is the largest randomized, double-blind, placebo-controlled study to date with individuals diagnosed with SPMS and included 1,651 people with SPMS from 31 countries. Study participants received either 2 mgs of the oral medication siponimod, taken once daily, or a placebo. These were given in a 2:1 ratio, so twice as many participants were on the active medication versus the placebo.

Siponimod, also known as BAF312, is in a class of immunomodulatory drugs called “S1P-receptor modulators.” According to MSAA’s MS Research Update in 2016, the structure of these medications is similar to a naturally occurring component of cell-surface receptors on white blood cells. These medications block potentially damaging T cells from leaving lymph nodes, lowering their number in the blood and tissues. They may reduce damage to the central nervous system (CNS) and enhance the repair of damaged nerves within the brain and spinal cord.

MSAA’s MS Research Update in 2016 also notes that another oral treatment for MS, Gilenya® (fingolimod), was the first S1P-receptor modulator approved for treating relapsing forms of MS and study data suggest that it may have neuro-protective effects. Siponimod is a similar medication to Gilenya and has a relatively short half-life, which means that the drug does not stay in the body as long. Researchers hope that this will minimize cardiac issues that are often seen with these types of medications.

While Novartis announced that the study met its primary endpoint, specific details on the results were not included. According to the press release, secondary endpoints include delay in the time to six-month confirmed disability progression versus placebo, time to confirmed worsening of at least 20 percent from baseline in the timed 25-foot walk test (T25FW), T2 lesion volume, annualized relapse rate (ARR), and the safety and tolerability of siponimod in people with SPMS. Initial results of the EXPAND study, including primary and key secondary endpoints, will be presented at the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) annual meeting, which will be held this September in London, England.

MSAA’s Chief Medical Consultant Dr. Jack Burks explains, “The possibility of having a treatment available to individuals with secondary-progressive MS is very exciting and brightens the future for everyone with this form of the disease. Readers should note that while the three-month data are encouraging, we await the results of the six-month findings, other secondary endpoints, and safety data. Additionally, we will get more insight into siponimod’s effectiveness with non-relapsing as well as relapsing SPMS patients. I look forward to learning about these and other details when new data are presented at ECTRIMS next month.”

For general information or to speak with a trained Client Services Specialist, please call MSAA’s Helpline at (800) 532-7667, extension 154. Questions to MSAA’s Client Services department may also be emailed to MSquestions@mymsaa.org.

Written by Susan Courtney, MSAA Senior Writer

Reviewed by Jack Burks, MD, MSAA Chief Medical Consultant

Portions of MSAA’s MS Research Update 2016, coauthored by Stephen Krieger, MD and Michelle Fabian, MD, were also included in this article.