Provided herein is a method of treating or preventing a disease or disorder (e.g., MS) in a subject in need thereof； comprising (a) administering to the subject a first dose of a pharmaceutical composition comprising a fumarate agent (e.g., DIVEF) for a first dosing period； (b) administering a vaccine； and (c) administering to the subject a second dose of the pharmaceutical composition for a second dosing period.
