An experimental oral drug for progressive multiple sclerosis is showing staying power. Open-label extension data from the phase 2 CALLIPER trial show that the disability benefits seen with vidofludimus calcium during the double-blind period held up with continued treatment. The drug's safety profile also remained consistent, with a low discontinuation rate of just 6.5%.
An investigational oral therapy for progressive multiple sclerosis (MS) is building a longer-term track record. New open-label extension (OLE) data from the phase 2 CALLIPER trial, presented at MSToronto2026, show that the favorable disability trends seen with vidofludimus calcium during the double-blind phase were maintained in patients who continued treatment. The drug works by activating Nurr1 and inhibiting DHODH — a dual mechanism targeting both neurodegeneration and inflammation.
The safety profile in the extension period looked reassuring and consistent with the earlier phase, with only 6.5% of patients discontinuing through the January 2026 data cutoff. Exploratory analyses also revealed an intriguing link between the drug and reduced Epstein-Barr virus (EBV)–specific immune activity, which correlated with better cognitive test scores — adding a potential mechanistic angle to the clinical findings.
Key Takeaways:
Why it matters: Progressive MS remains one of the hardest-to-treat neurological conditions, with few approved therapies. These sustained OLE results, combined with a phase 3 trial planned for later in 2026, keep vidofludimus calcium on the radar as a potential new option for this underserved patient population.
