An Extension Protocol for Multiple Sclerosis Patients Who Participated in Genzyme-Sponsored Studies of Alemtuzumab

Inclusion Criteria:

   - 1.Received alemtuzumab in CAMMS323 or CAMMS324, completed the 2-year study period, and
   had not subsequently received disease modifying treatments (other than glatiramer
   acetate or interferon beta); or

   - 2.Received Rebif® in CAMMS323 or CAMMS324, completed the 2-year study period, and had
   not subsequently received alternative disease modifying treatments (other than
   glatiramer acetate or another interferon beta); or

   - 3.Participated in CAMMS223.

   - NOTE: Criteria 1 and 2 above meant that participants who enrolled in CAMMS323 or
   CAMMS324 but did not complete the 2-year study period or went on to receive non-study
   drug DMTs after randomization were not eligible for inclusion in the Extension Study.
   Participants who enrolled in CAMMS324 after participation in CAMMS223 must meet
   criteria 1 or 2 to be eligible for inclusion in the Extension Study.

Exclusion Criteria:

   - Any alemtuzumab participant from CAMMS223, CAMMS323, or CAMMS324 who had received
   alemtuzumab off-label (ie, outside of one of the prior Genzyme-sponsored studies), or
   was participating in any other investigational study, unless approved by Genzyme. In
   addition, these participants must be screened for disqualifying safety concerns before
   receiving alemtuzumab retreatment.

   - Any Rebif® participants from CAMMS223, CAMMS323, or CAMMS324 who met any of the
   following criteria. In addition, these participants must be screened for disqualifying
   safety concerns before receiving alemtuzumab treatment. a) Did not wish to receive
   alemtuzumab; b) Ongoing participation in any other investigational study, unless
   approved by Genzyme; c) Had received alemtuzumab off-label (ie, outside of one of the
   prior Genzyme-sponsored studies); d) Known bleeding disorder or therapeutic
   anticoagulation; e) Diagnosis of idiopathic thrombocytopenia purpura or other
   autoimmune hematologic abnormality; f) History of malignancy, except basal cell skin
   carcinoma; g) Intolerance of pulsed corticosteroids, especially a history of steroid
   psychosis h) Significant Autoimmune disorder (other than MS); i) Major psychiatric
   disorder or epileptic seizures not adequately controlled by treatment; j) Active
   infection or high risk for infection k) Unwilling to use a reliable and acceptable
   contraceptive method during and for at least 6 months following each alemtuzumab
   treatment cycle (fertile participants only).