This invention provides a method of treating a subject afflicted with multiple sclerosis or presenting a clinically isolated syndrome comprising administering to the subject laquinimod as an add-on therapy to or in combination with flupirtine. This invention also provides a package and a pharmaceutical composition comprising laquinimod and flupirtine for treating a subject afflicted with multiple sclerosis or presenting a clinically isolated syndrome. This invention also provides laquinimod for use as an add-on therapy or in combination with flupirtine in treating a subject afflicted with multiple sclerosis or presenting a clinically isolated syndrome. This invention further provides use of laquinimod and flupirtine in the preparation of a combination for treating a subject afflicted with multiple sclerosis or presenting a clinically isolated syndrome.