ACUITY

Treatment tested

• OCS-05 +SoC (corticosteroid) IV administration
• ACT-01

Placebo or sham

• Placebo + SoC (corticosteroid) IV administration

Other measures (13)

Main Inclusion Criteria: * Diagnosed with a unilateral optic neuritis * Onset of visual loss symptoms in the last 12 days before randomization Main Exclusion Criteria: * Optic neuropathy of non-demyelinating origin * Known Neuromyelitis optica with autoantibodies against aquaporin-4 (AQP4-Abs) * Patients with widespread and symmetric white matter alterations in the screening MRI suggestive of other demyelinating disorders (e.g. metabolic disorders, mitochondrial disorders) * Active, chronic disease (or stable but treated with immune therapy) of the immune system other than Multiple Sclerosis (MS) or Myelin Oligodendrocyte Glycoprotein Antibody associated Disorder (MOGAD)(e.g. Sjögren's disease, systemic lupus erythematosus) or with a known immunodeficiency syndrome (AIDS, hereditary immune deficiency, drug induced immune deficiency) * An alternative cause of visual loss (e.g. compressive or infiltrative lesion of the optic nerve, infections, genetic forms of visual loss. * Diagnosed with macular edema, severe myopia (>6 δ) or other disease of the retina at inclusion * Known diabetic retinopathy * Known glaucoma * Female patients of child-bearing potential who are unwilling to use an effective contraception while enrolled on study and for the duration of the study. * Male patients not willing to use contraception (abstinence, condom etc..) while enrolled in the study and receiving the experimental drug, and for at least 2 days after the last experimental drug administration. * Breastfeeding or pregnant women

To evaluate the safety and tolerability of OCS-05 compared to placebo in patients with optic neuritis receiving the standard of care