A new drug for multiple sclerosis could slow the progression of symptoms of a form of the disease for which effective treatments have proved elusive, research suggests.

It is thought about 100,000 people in the UK and 2,500,000 people worldwide have MS, a neurological condition that can affect speech, movement of limbs and vision, among other things.

Secondary progressive MS develops in many people who are initially diagnosed with the relapsing-remitting form, in which individuals experience symptoms in distinct flare-ups, and involves disabilities getting worse over time.

The new findings, based on a large international clinical trial, found a drug called siponimod reduced the risk of disabilities becoming worse over time.



“I think this a potentially landmark-type study,” said Dr Matt Craner, clinical lead of the MS clinical trials unit at the University of Oxford, who was involved in the study.



While Craner admitted that the effects of the drug were modest, he said the findings were important. “You are looking at a population of patients that have no treatments – there is nothing available currently for secondary progressive MS,” he said.

The latest research comes in the same week that doctors revealed the latest results for a promising therapy for relapsing remitting MS, involving cancer drugs and a stem cell transplant.



In the new study, published in the Lancet and funded by Novartis Pharma AG, Craner and colleagues describe how 1,055 adults with secondary progressive MS were given siponimod and 545 were given a placebo. Neither the doctors nor participants were aware at the time which treatment was being given, and participants took the drug for anywhere up to 37 months.

Every three months, participants’ levels of disability were assessed, and an increase was dubbed “confirmed” if it persisted for a further three months.

The team found that while 32% of those in the placebo group experienced a progression in disability during the study, the same was true for only 26% of those in the siponimod group – a 21% reduction in risk of such a progression. The findings were strongest for certain groups, including those who had had recent attacks and those with less disability to start with.

No difference was found between the drug groups when researchers repeatedly looked at the time it took for participants to walk 25 feet.

MRI brain scans at the start of the study, and again at 12 and 24 months, showed that those in the siponimod group had a slower rate of brain shrinkage, suggesting less tissue damage, and had less increase in brain scarring. But, the team note, the study setup means that some of those labelled as being in the placebo group could, by the time of the brain scans, be taking siponimod.

The findings have received a mixed response.

An accompanying commentary by Luanne Metz and Wei-Qiao Liu from the University of Calgary struck a downbeat tone, noting the treatment effect was small and that not all measures, such as the walking test, showed improvements under siponimod. That, they write, means the results “do not suggest that siponimod is an effective treatment for” secondary progressive MS.

But Prof Alasdair Coles, an expert in MS from the University of Cambridge, dismissed the walking measure as a “rubbish test” that could be affected by a host of factors and welcomed the findings.

“At a political level this is fantastic because for the first time a drug which is reasonably safe to take has any impact at all on secondary progressive MS,” he said, adding that it will spur on further research into tackling the condition.

But he had reservations, predicting the National Institute for Health and Care Excellence will not consider the drug cost-effective given the modest size of the effects, and adding that other drugs were known to produce similar results for brain scarring and shrinkage.

What’s more, Coles said, the observed benefits of siponimod might only be down to its anti-inflammatory effects, with results only seen among patients with high levels of inflammation and that only showed up because of the large trial size.



But he said there is an additional, far more exciting, possibility: that siponimod might also promote recovery of the insulating sheaths around neurons – coatings that are damaged in MS – and prevent degeneration of connections between neurons.



“That definitely needs to be run down because we desperately need a treatment that does that,” he said.