Phase II clinical trial of neuroprotection with Phenytoin in acute optic neuritis
A case study of drug repurposing from Dr Raj Kapoor

13 January 2020
Principal Investigator: Dr Raj Kapoor, Institute of Neurology
Unmet Medical Need: Acute demyelinating optic neuritis, (common feature of multiple sclerosis) can damage vision through neurodegeneration in the optic nerve and in its fibres in the retina.
Current treatment: Corticosteroids help vision to recover more quickly, but do not improve on the overall extent of recovery compared to untreated.
Project:
- Inhibition of voltage-gated sodium channels is neuroprotective in preclinical models.
- Is sodium-channel inhibition with phenytoin neuroprotective in patients with acute optic neuritis?
- Ran randomised, placebo-controlled, double-blind phase 2 trial at two leading UK academic hospitals
Funders: National Multiple Sclerosis Society and the UK MS Society
Outcome: Trial results support the concept of neuroprotection using phenytoin to inhibit voltage-gated sodium channels in patients with acute optic neuritis
Next stage: Further investigation in larger clinical trials in optic neuritis and in relapsing multiple sclerosis is warranted.