Efficacy and Safety of Daclizumab in Participants With RRMS Switching From 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.