CLARITY Extension Study

Inclusion Criteria:

Randomized in Trial 25643 and satisfied one of the following:

Completed randomized treatment course and scheduled visits for the full 96 weeks; or
Did not complete the randomized treatment course in Trial 25643 but elected to receive rescue treatment with Rebif®, another beta-interferon, or glatiramer acetate and completed scheduled clinic visits for the full 96 weeks; or
Did not complete the randomized treatment course in Trial 25643, declined rescue with Rebif®, another beta-interferon, or glatiramer acetate and still completed scheduled clinic visits for the full 96 weeks; or
Did not complete the randomized treatment course in Trial 25643, were not eligible for rescue option with Rebif®, and still completed scheduled clinic visits for the full 96 weeks
Male or female, between 18 and 65 years of age (inclusive, at time of informed consent for Trial 25643)
No medical history or evidence of latent tuberculosis infection (LTBI) or tuberculosis (TB), as evidenced by TB skin test or chest X-ray

All of the following laboratory hematologic parameters evaluated as normal (as define below, inclusively) within 28 days of first dosing of blinded study medication at study Day 1:

Hemoglobin = 11.6 to 16.2 gram per deciliter (g/dL)
Leukocytes (total white blood cell) = 4.1 to 12.3*10^3 per microliter
Absolute lymphocyte count (ALC) = 1.02 to 3.36*10^3 per microliter
Absolute neutrophil count (ANC) = 2.03 to 8.36*10^3 per microliter
Platelet count = 140 to 450*10^3 per microliter
Other protocol-defined inclusion/exclusion criteria may apply

Exclusion Criteria:

Participants who were not enrolled in Trial 25643
Participant has moderate to severe renal impairment
Use of mitoxantrone, total lymphoid irradiation, myelosuppressive therapy, campath-1h, cyclophosphamide, azathioprine, methotrexate or natalizumab at any time during and since Trial 25643
Use of cytokine or anti-cytokine therapy, intravenous immunoglobulin (IVIG) or plasmapheresis at any time during and since Trial 25643
Treatment with oral or systemic corticosteroids or adrenocorticotropic hormone within 28 days before Study Day 1