Novartis has unveiled further findings from a late-stage trial of its experimental multiple sclerosis drug BAF312 (siponimod), showing that the drug cut the risk of disability progression in adults with secondary progressive forms of the disease.

Secondary progressive multiple sclerosis (SPMS) is a type of MS characterised by continuous worsening of neurological function over time, independent of relapses. Most people with relapsing remitting forms of MS will eventually go on to develop SPMS; on average, around 65 percent will develop SPMS 15 years after being diagnosed, according to the MS Society.

Siponimod is a selective modulator of specific types of the sphingosine-1-phosphate (S1P) receptor, commonly found on the surface of specific cells in the central nervous system responsible for causing damage that drives loss of function in SPMS. The drug enters the brain binding to these specific receptors, which may prevent the activation of these harmful cells, potentially helping to reduce loss of physical and cognitive function associated with the condition.

Top-line data from the Phase III EXPAND study show that treatment with siponimod reduced the risk of three-month confirmed disability progression by 21 percent compared with placebo, and there was also a consistent reduction in the risk across predefined subgroups, including patients without relapse, the firm said.

Also observed was a significant difference in favour of siponimod versus placebo in annualised relapse rate, the percent change in brain volume, and change from baseline in the volume of T2 lesions, though the difference in change from baseline in the Timed 25-Foot Walk test was not significant.

In the trial, which Novartis claims is the largest randomised, controlled study in SPMS to date, the drug was found to be generally safe and well tolerated, with a profile comparable to others in the same class.

"There are very few available treatment options to delay disease progression in SPMS, and there is a high unmet need for effective therapies with an acceptable safety profile for people with the condition," said Vasant Narasimhan, global head Drug Development and chief medical officer at Novartis.

"These data are a positive stride forward in an unserved disease area, and we look forward to evaluating next steps with health authorities."