The phase III EXPAND trial recruited 1651 people with secondary progressive MS. On average, participants had been diagnosed with MS for approximately 17 years, and had had SPMS for about 4 years. Just over half needed walking assistance. Participants took either siponimod (1105) or placebo (546) daily for up to 3 years.
Disability level (EDSS score) was assessed every three months. Disability progression was confirmed if an increase in EDSS was maintained for 3 months.
Researchers found that 32% of those taking placebo experienced a 3 month confirmed increase in disability during the study, compared to 26% of those taking siponimod. This represented a 21% reduction in risk of progression for those taking siponimod.
Siponimod was also more effective than placebo on other measures used in the study:
- reduced risk of 6 month confirmed increase in disability
- reduced loss of brain volume
- reduced MRI-detected brain lesion volume
There was no significant difference between the two groups in the time taken to walk 25 feet.
Low white blood cell count, increased liver enzyme levels, slower heart rate when starting treatment, macular oedema (swelling in the back of the eye affecting vision), high blood pressure, shingles, and convulsions occurred more frequently with siponimod than with placebo.
These results have previously been presented at conferences, but this is the first time they have been published in a peer-reviewed journal, which is the gold standard in clinical research.
This is very encouraging news for people with SPMS. There has never been a positive result in a phase III trial of this kind and it is cause for greater hope that there is a treatment that could have an effect on disability. We look forward to hearing more detail about the trial and whether the positive effects on disability can be sustained over the longer term.
Jo Sopala, Director of Development
What next for siponimod?
Novartis, the manufacturer of siponimod, plans to apply for a European licence for the treatment in the second half of this year. Siponimod will then be appraised for cost effectiveness as an NHS treatment. If these steps are successful siponimod could be available on the NHS towards the end of 2019 at the earliest.
Kappos L, et al.
Siponimod versus placebo in secondary progressive multiple sclerosis (EXPAND): a double-blind, randomised, phase 3 study
Lancet 2018 Mar 22. [Epub ahead of print]