Transition to Rebif New Formulation

Inclusion Criteria: * Subject with relapsing forms of Multiple Sclerosis (MS) * Expanded disability status scale (EDSS) score \< 5.5 at study entry * Subjects who have been administering Rebif 44 mcg three times a week for at least 6 months prior to study enrolment * Subject currently using Rebiject II and who will use their own Rebiject II for the Rebif New Formulation injections * Subject is between 18 and 60 years old inclusive * Female subjects must be neither pregnant nor breast-feeding and must lack childbearing potential, as defined by either: post-menopausal or surgically sterile, or use a highly effective method of contraception. * Subject is willing to follow study procedures * Subject is willing and must not present any contra-indication to taking ibuprofen during 4 weeks of the study * Subject has given written informed consent Exclusion Criteria: * Secondary Progressive Multiple Sclerosis without superimposed attacks * Use of any other injectible medications during the week prior to the screening period, during the screening or treatment periods * Subject receiving MS therapy in addition (i.e. combination therapy) to Rebif within 3 months prior to study enrolment or at any time during study protocol * History of any chronic pain syndrome * Subjects that use any investigational drug or experimental procedure within 12 weeks of visit * Subject received corticosteroids or adrenocorticotrophic hormone (ACTH) within 30 days of visit 1 * Subject with flu-like symptoms (FLS) associated with any cause (i.e. no current flu and no FLS related to Interferon in the week prior to baseline) * Subject has abnormal liver function, defined by a total bilirubin \> 1.5 times the upper limit of normal, aspartate aminotransferase (AST) or alanine aminotransferase (ALT) \> 2.5 times the upper limit of the normal values. * Subject has inadequate bone marrow reserve, defined as a total white blood cell count \< 3.0 x 109/L, platelet count \< 75 x 109/L, haemoglobin \< 100 g/L. * Subject suffers from an active autoimmune disease other than MS * Subject suffers from major medical or psychiatric illness * Subject has seizures history or is currently experiencing seizures not adequately controlled by anti-epileptics * Subject is pregnant or attempting to conceive * Visual or physical impairment that precludes completion of diaries and questionnaires by himself/herself * Contraindication to ibuprofen:known hypersensitivity to the active ingredient ibuprofen * Known hypersensitivity to non-steroidal anti-inflammatory drugs which can lead to asthmatic attacks, gastric and/or intestinal ulcers, gastro-intestinal bleeding, cerebro-vascular bleeding or other active bleeding, severe hepatic dysfunction, severe kidney dysfunction, severe cardiac insufficiency, or systemic lupus erythematosus