Siponimod Enters Crowded Market of DMTs for SPMS

Siponimod is effective at reducing relapses in patients with active secondary-progressive multiple sclerosis (SPMS), but the drug will face challenges in an increasingly crowded, high-cost category of medication. 

Those are the takeaways from the Institute for Clinical and Economic Review, which reviewed siponimod back in June 2019 and published its findings in the Journal of Managed Care & Specialty Pharmacy in March.

While the US Food and Drug Administration (FDA) approved the disease modifying therapy (DMT) for the treatment of relapsing forms of MS, including active SPMS, the ICER report, like the phase III trial on which it is based, focused on both active and non-active patients.

The findings, though mixed, were in line with those of other DMTs. The ICER panel found that the drug is superior to best supportive care in patients with active SMPS, though some panelists noted concerns about the design of the trial. In the case of non-active SPMS, the panel found insufficient evidence that it improved upon the best supportive care.

Related: In Secondary-Progressive Multiple Sclerosis, Questions Abound, But so do Breakthroughs

David Whitrap, a spokesman for ICER, said one challenge in treating SPMS is that MS treatments generally target the active relapses of the disease, but it’s been much more difficult to find treatments to stop the underlying progression that seems to be ongoing even in “non-active” SPMS.

“Relapsing MS seems to clearly have an autoimmune component, and so we give therapies targeting the immune system,” he told Managed Healthcare Executive. “Non-active SPMS progressively results in disability, so having a therapy that stopped that progression would be a huge deal for patients.”

The ICER report noted that the phase III EXPAND trial for siponimod found the therapy reduced the risk of 3-month confirmed disability progression on the Expanded Disability Status Scale (EDSS). It also decreased disease activity as measured by MRI, such as the number of gadolinium-enhancing lesions on T1-weighted scans. The study did not find observable improvement in certain mobility measures, such as the timed 25-foot walk test and the 12-point Multiple Sclerosis Walking Scale. 

Whitrap said the issue facing siponimod is that it’s in a high-cost, highly competitive drug category. The ICER report used the wholesale acquisition cost of $88,561 in its analysis of siponimod. That translated into an estimated cost of $433,000 per quality-adjusted life year compared to best supportive care in patients with active SPMS. The estimated cost per life year gained was $1.57 million. ICER did not evaluate the cost-effectiveness of the drug in patients with relapsing-remitting MS, for which the therapy is also approved. The institute also declined to calculate a price benchmark, Whitrap said.

“Because our assessment did not align neatly with the FDA’s label, we did not recommend an official ‘value-based price benchmark,’” he explained.

Whitrap noted that one competitor in particular, fingolimod, has a similar mechanism of action and will soon have generic forms. The FDA approved three generic versions of fingolimod back in December. ICER’s report suggests payers might want to grant preferential formulary status to these generics once they become available on the market.