For all randomized subjects, there is a rescue option of treatment with Rebif® (interferon beta-1a 44 microgram (mcg) given subcutaneously three times a week), if the subject experienced more than one qualifying relapse, and/or experienced a sustained increase in their EDSS score of greater than or equal to (>=) 1 point, or >=1.5 points if baseline EDSS score is 0, (over a period of three months or greater), during a calendar year beginning at Week 24.