- On continual treatment for ≥6 months with a single standard-of-care subcutaneous (SC) interferon beta (IFN-β) therapy, including IFN β-1b 0.25 mg SC every other day or IFN β-1a 44 μg SC 3 times weekly, and from a clinical perspective be able to continue this therapy (i.e., no significant untoward events attributed to IFN therapy that would preclude continuation of the existing IFN therapy).