Transition to Rebif New Formulation

To assess patient satisfaction with respect to the incidence of flu-like symptoms (FLS) in patients with multiple sclerosis transitioned from current Rebif (subcutaneously injected interferon beta-1a, 44 mcg three-times-weekly) to the new formulation of Rebif (RNF) while receiving ibuprofen either prophylactically or only when necessary (PRN) after the occurence of flu-like symptoms.


Eligibility Criteria:
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