Novartis’ experimental multiple sclerosis therapy siponimod is on the brink of being filed in the US.

An application will be submitted to US regulators early this year seeking permission to market the drug for secondary progressive multiple sclerosis (SPMS), a type of MS characterised by continuous worsening of neurological function over time, independent of relapses.

A filing in Europe is on the cards for later in the year, following scientific consultation with the European Medicines Agency, the Swiss drug giant said.

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.

Full data from the Phase III EXPAND study, published in The Lancet, show significant reductions in the risk of three- (primary endpoint) and six-month confirmed disability progression with siponimod versus placebo and favorable outcomes in other relevant measures of MS disease activity.

According to the data, the drug cut the risk of three-month confirmed disability progression by 21 percent, the risk of six-month confirmed disability progression by 26 percent, and the annualised relapse rate by 55 percent versus placebo.

Novartis says that if approved, siponimod would be the first disease-modifying therapy to delay disability progression in typical SPMS patients, including many who had reached a non-relapsing stage and high level of disability.

"The pivotal EXPAND data provides patients, and the medical community alike, with hope that a much needed, safe and effective treatment option is on the horizon for SPMS, for which treatment options are scarce," said Danny Bar-Zohar, global head, Neuroscience Development for Novartis.