Vidofludimus is a new drug treatment under investigation for relapsing remitting, secondary progressive and primary progressive multiple sclerosis (MS). It is taken as a tablet once daily.
Vidofludimus for relapsing remitting MS: Phase III
Vidofludimus for secondary progressive MS: Phase II
Vidofludimus for primary progressive MS: Phase II
- Vidofludimus reduces the activity of T-cells and B-cells, which are types of white blood cell involved in the immune response that damages the myelin coating of nerves.
- In relapsing remitting MS, vidofludimus reduced the number of new active lesions on MRI.
- The most common side effects in a clinical study were hair thinning, fatigue, rash and cystitis (urinary tract infection).
Vidofludimus blocks an enzyme (dihydroorotate dehydrogenase, DHODH) which is essential for the growth of activated T-cells and B-cells, white blood cells involved in the immune response that damages the myelin coating of nerves in the brain and spinal cord. The drug is thought to reduce inflammation around the nerves.
The drug also activates a cellular process that helps to protect damaged nerves and may act as a broad antiviral medicine. This means that any Epstein-Barr virus (EBV) in the body is prevented from reactivating. The manufacturers think that this action may help to reduce progression and fatigue.
Vidofludimus has a similar mechanism of action to Aubagio (teriflunomide) but is expected to have a more targeted effect, reducing the risk of side effects.
Vidofludimus is taken as a tablet, once daily.
In the phase II Emphasis study, 210 people with relapsing remitting MS took one of two doses of vidofludimus or placebo for 24 weeks. The main measure was the number of new active lesions seen on MRI. Vidofludimus significantly reduced the number of lesions compared to placebo.
An open-label extension of this trial is ongoing. This means that the participants can continue taking vidofludimus calcium or switch to it if they were on the placebo arm of the trial. They will continue to be monitored and this research will be published.
ENSURE I and 2 – vidofludimus compared to placebo, in relapsing remitting MS
These identical phase III studies will recruit 2100 participants with relapsing remitting and active secondary progressive MS. One half will take vidofludimus and the other half placebo for 18 months. The main measure of these studies is the time to first relapse. Additional measures include worsening of disability, lesions visible on MRI scans, cognition and loss of brain volume.
Recruitment for these trials is still ongoing.
Further details of ENSURE 1
Further details of ENSURE 2
Study website
CALLIPER – vidofludimus compared to placebo, in secondary and primary progressive MS
This phase II study has recruited 467 participants with primary or secondary (active or non-active) progressive MS. One half will take vidofludimus and the other half will take placebo for approximately 6 months. The main aims of the study are to assess the effect of vidofludimus on brain volume change and on disability progression, measured as worsening of disability which persists for six months. The study will also monitor safety and tolerability of vidofludimus and evaluate any effect of the drug on EBV activity.
Estimated completion date is April 2025, but an interim analysis published in February 2024 indicated that people in the study taking vidofludimus calcium had 22.4% reduction in serum neurofilament levels. Neurofilaments are used as an indicator of nerve damage, so the researchers interpret this as showing that vidofludimus calcium acts in a neuroprotective way.
Further details of CALLIPER
The main side effects reported in the phase II clinical trial were:
