Efficacy and Safety of Daclizumab in Participants With RRMS Switching From Natalizumab
Efficacy and Safety of Daclizumab in Participants With RRMS Switching From Natalizumab
The primary objective of the study is to evaluate the effects of treatment with daclizumab on
 the proportion of participants relapse-free at 6 months in Relapsing-Remitting Multiple
 Sclerosis (RRMS) participants, who switched from treatment with natalizumab to daclizumab due
 to safety concerns. The secondary objectives of this study in this study population are to
 evaluate the effects of daclizumab on the following: 1) Multiple Sclerosis (MS) relapse
 activity including the annualized relapse rate (ARR) and the proportion of participants
 experiencing relapses requiring hospitalization and/or steroid treatment; 2) MS-related
 outcomes measured using magnetic resonance imaging (MRI); 3) Safety and tolerability in
 participants previously treated with natalizumab.
Key Inclusion Criteria

 -  Must have documented diagnosis of RRMS (McDonald 2010 Criteria) at screening [Polman
 2011].

 -  Must have been treated with natalizumab for at least the 12 months prior to screening
 and have not missed 2 or more consecutive scheduled doses.

 -  Must be naïve to daclizumab and other forms of daclizumab such as Zenapax® prior to
 enrollment.

 -  Must have a confirmed Expanded Disability Status Scale (EDSS) score of 0 to 5.5,
 inclusive, at screening.

 -  Female participants of childbearing potential must practice effective contraception
 from Day -1 and be willing and able to continue contraception for duration of the
 study.

 Key Exclusion Criteria

 -  Current participation in another investigational study.

 -  Diagnosis of primary progressive, secondary progressive, or progressive relapsing MS
 (as defined by Lublin and Reingold) [Lublin 2014].

 -  Females breastfeeding, pregnant, or planning to become pregnant; or women who have a
 positive pregnancy test result during screening.

 -  History of drug or alcohol abuse (as defined by the Investigator) within 1 year prior
 to screening.

 -  History of severe hypersensitivity (e.g., anaphylaxis or anaphylactoid reactions) to
 the active ingredient or any of the excipients.

 -  History of severe opportunistic infections (including progressive multifocal
 leukoencephalopathy (PML)) or any clinically significant, cardiac, endocrinologic,
 hematologic, hepatic, immunologic, metabolic, urologic, pulmonary, neurologic (other
 than MS), dermatologic, psychiatric, and renal, or other major disease, as determined
 by the Investigator.

 -  Discontinued natalizumab due to suspicion of PML.

 -  Known active malignancies (participants with cutaneous basal cell carcinoma that has
 been completely excised prior to study entry remain eligible).

 -  The participant is using another MS therapy concomitantly.

 -  Known history of human immunodeficiency virus (HIV).

 -  Positive test result for Hepatitis C virus (test for hepatitis C virus antibody [HCV
 Ab]) or hepatitis B virus (test for hepatitis B surface antigen [HBsAg] and/or
 hepatitis B core antibody [HBcAb]).

 -  The participant has been treated with immunosuppressive or immunomodulating treatments
 including mitoxantrone, azathioprine, methotrexate, cyclophosphamide, or mycophenolate
 mofetil.

 NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.