A Study in Subjects With Relapsing-Remitting Multiple Sclerosis (RRMS) to Assess the Efficacy, Safety and Tolerability of Glatiramer Acetate (GA) Injection 40 mg Administered Three Times a Week Compared to Placebo

The study is designed to assess the efficacy of Glatiramer Acetate (GA) injection 40 mg administered three times a week compared to placebo in subjects with RRMS, as measured by the number of confirmed relapses during the 12 month placebo controlled period. The study has two periods:

* Placebo Controlled Period: 12 months of 40 mg administered three times a week by subcutaneous injection or matching placebo.
* Open Label Extension Period: All subjects will continue treatment with GA 40 mg administered three times a week, until this dose strength is commercially available for the treatment of relapsing remitting multiple sclerosis (RRMS) patients or until the development of this GA dose regimen is stopped by the Sponsor

Participants who were randomized to the GA 40 mg treatment arm in the Double-Blind Period, continue that treatment in the Open-Label Extension Period and are referred to as "Early Start" participants. Participants randomized to the Placebo arm in the Double-Blind Period and switched to GA 40 mg subcutaneous injections three times a week in the Open-Label Extension are referred to as "Delayed Start" participants.

Eligibility Criteria:
Inclusion Criteria:

1. Subjects must have a confirmed and documented MS diagnosis as defined by the Revised McDonald criteria with a relapsing-remitting disease course.
2. Subjects must be ambulatory with an EDSS score of 0-5.5 in both screening and baseline visits.
3. Subjects must be in a relapse-free, stable neurological condition and free of corticosteroid treatment \[intravenous (IV), intramuscular (IM) and/or per os (PO)\] or ACTH 30 days prior to screening (month -1) and between screening and baseline (month 0) visits.
4. Subjects must have experienced one of the following:

   At least one documented relapse in the 12 months prior to screening, or At least two documented relapses in the 24 months prior to screening, or One documented relapse between 12 and 24 months prior to screening with at least one documented T1-Gd enhancing lesion in an MRI performed within 12 months prior to screening.
5. Subjects must be between 18 and 55 years of age, inclusive.
6. Women of child-bearing potential must practice an acceptable method of birth control.
7. Subjects must be able to sign and date a written informed consent prior to entering the study.
8. Subjects must be willing and able to comply with the protocol requirements for the duration of the study

Exclusion Criteria:

1. Subjects with progressive forms of MS.
2. Use of experimental or investigational drugs, and/or participation in drug clinical studies within the 6 months prior to screening.
3. Use of immunosuppressive (including Mitoxantrone and Fingolimod) or cytotoxic agents within 6 months prior to the screening visit.
4. Use of natalizumab (Tysabri®) or any other monoclonal antibodies within 2 years prior to screening.
5. Use of cladribine within 2 years prior to screening.
6. Previous treatment with immunomodulators (including IFNβ 1a and 1b, and IV Immunoglobulin (IVIg) within 2 months prior to screening.
7. Previous use of GA or any other glatiramoid.
8. Chronic (more than 30 consecutive days) systemic (IV, PO or IM) corticosteroid treatment within 6 months prior to screening visit.
9. Previous total body irradiation or total lymphoid irradiation.
10. Previous stem-cell treatment, autologous bone marrow transplantation or allogenic bone marrow transplantation.
11. Pregnancy or breastfeeding.
12. Subjects with a clinically significant or unstable medical or surgical condition that would preclude safe and complete study participation, as determined by medical history, physical exams, ECG, abnormal laboratory tests and chest X-ray. Such conditions may include hepatic, renal or metabolic diseases, systemic disease, acute infection, current malignancy or recent history (5 years) of malignancy, major psychiatric disorder, history of drug and/or alcohol abuse and allergies that could be detrimental according to the investigator's judgment.
13. A known history of sensitivity to Gadolinium.
14. Inability to successfully undergo MRI scanning.
15. A known drug hypersensitivity to Mannitol.