Long-Term Extension Study in Participants With Multiple Sclerosis Who Have Completed Study 205MS301 (NCT01064401) to Evaluate the Safety and Efficacy of BIIB019

Relapses are defined as new or recurrent neurological symptoms not associated with fever or infection, lasting at least 24 hours, and accompanied by new objective neurological findings upon examination by the Study Neurologist. The unadjusted ARR was calculated by tabulating the total number of relapses experienced in the group divided by the number of days up to the end of study, and the ratio then multiplied by 365.25. Relapses that occurred after participants received alternative multiple sclerosis (MS) medications were excluded from the analyses. ARR was adjusted for relapse rate, IFN beta use, Expanded Disability Status Scale (EDSS) (<=2.5 vs >2.5) and age (<=35 vs >35) prior to start of study treatment in 205MS301, calculated using the negative binomial model.

Relapses are defined as new or recurrent neurological symptoms not associated with fever or infection, lasting at least 24 hours, and accompanied by new objective neurological findings upon examination by the Study Neurologist. The unadjusted ARR was calculated by tabulating the total number of relapses experienced in the group divided by the number of days up to the end of study, and the ratio then multiplied by 365.25. Relapses that occurred after participants received alternative MS medications were excluded from the analyses. ARR was adjusted for relapse rate, IFN beta use, EDSS (<=2.5 vs >2.5) and age (<=35 vs >35) prior to start of study treatment in 301, calculated using the negative binomial model.

Relapses are defined as new or recurrent neurological symptoms not associated with fever or infection, lasting at least 24 hours, and accompanied by new objective neurological findings upon examination by the Study Neurologist.

Relapses are defined as new or recurrent neurological symptoms not associated with fever or infection, lasting at least 24 hours, and accompanied by new objective neurological findings upon examination by the Study Neurologist.

Sustained disability progression is defined as at least a 1.0-point increase on the Expanded Disability Status Scale (EDSS) from 303 baseline EDSS ≥1.0 that is sustained for 24 weeks, or at least a 1.5-point increase on the EDSS from 303 baseline EDSS of 0, that is sustained for 24 weeks. The EDSS measures the disability status of people with multiple sclerosis on a scale that ranges from 0 to 10. The range of main categories include (0) =normal neurologic exam; to (5) = ambulatory without aid or rest for 200 meters; disability severe enough to impair full daily activities; to (10) = death due to MS. Higher scores indicate more disability.

Sustained disability progression is defined as at least a 1.0-point increase on the Expanded Disability Status Scale (EDSS) from 303 baseline EDSS ≥1.0 that is sustained for 24 weeks, or at least a 1.5-point increase on the EDSS from 303 baseline EDSS of 0, that is sustained for 24 weeks. The EDSS measures the disability status of people with multiple sclerosis on a scale that ranges from 0 to 10. The range of main categories include (0) =normal neurologic exam; to (5) = ambulatory without aid or rest for 200 meters; disability severe enough to impair full daily activities; to (10) = death due to MS. Higher scores indicate more disability.

T2 Hyperintense Lesions were assessed by magnetic resonance imaging (MRI) and were analyzed by a central MRI reader. The number of participants with New or Newly Enlarging T2 Hyperintense Lesions relative to the 303 Baseline in the 303 Treatment Period is reported.

T2 Hyperintense Lesions were assessed by MRI and were analyzed by a central MRI reader. The number of participants with New or Newly Enlarging T2 Hyperintense Lesions relative to the 301 Baseline in the 301 Treatment Period is reported.

Gd+ lesions were evaluated by MRI and were analyzed by a central MRI reader.

Gd+ lesions were evaluated by MRI and were analyzed by a central MRI reader.

T1 hypointense lesions were evaluated by MRI and were analyzed by a central MRI reader. The number of participants with New T1 Hyperintense Lesions relative to the 303 Baseline in the 303 Treatment Period is reported.

T1 hypointense lesions were evaluated by MRI and were analyzed by a central MRI reader. The number of participants with New T1 Hyperintense Lesions relative to the 301 Baseline in the 301 Treatment Period is reported .

To assess brain atrophy, total brain volume was measured by MRI and was analyzed by a central MRI reader. A negative percent change from baseline indicates improvement.

To assess brain atrophy, total brain volume was measured by MRI and was analyzed by a central MRI reader. A negative percent change from baseline indicates improvement.

Volume of T2 hyperintense Lesions was evaluated by MRI and was analyzed by a central MRI reader.

MSFC is a three-part, standardized, quantitative, assessment instrument consisting of (Timed 25-Foot Walk, Nine-Hole Peg Test (9HPT) and Paced Auditory Serial Addition Test (PASAT-3"). 2 timed 25-foot walk scores are averaged. 4 trials of the Peg Test (2 for each hand) are converted to the reciprocals and averaged. The number correct of the PASAT-3 is used. The composite Z-score is calculated by: Z(25-foot walk) + Z (HPT) + Z(PASAT)/3. A positive change from baseline indicates improvement.

MSFC is a three-part, standardized, quantitative, assessment instrument consisting of (Timed 25-Foot Walk, Nine-Hole Peg Test (9HPT) and Paced Auditory Serial Addition Test (PASAT-3"). 2 timed 25-foot walk scores are averaged. 4 trials of the Peg Test (2 for each hand) are converted to the reciprocals and averaged. The number correct of the PASAT-3 is used. The composite Z-score is calculated by: Z(25-foot walk) + Z (HPT) + Z(PASAT)/3. A positive change from baseline indicates improvement.

The EDSS measures the disability status of people with multiple sclerosis as assessed by the Study Neurologist based on 8 functional systems that ranges from 0=normal neurologic exam; to 5=ambulatory without aid or rest for 200 meters; disability severe enough to impair full daily activities; to 10=death due to MS. Higher scores indicate more disability. A negative change from Baseline indicates improvement.

Participants without clinical or radiological activity are defined as disease-free. Clinical activity includes assessment of relapses and of disease progression. Radiological activity includes assessments of Gd+ lesions and new or enlarging T2 lesions.

The 29-item MSIS-29 is a disease specific participant-reported outcome measure that has been developed and validated to examine the physical (coordination and mobility) and psychological (mental) impact of MS from a participant's perspective; it measures 20 physical items and 9 psychological items. The results for each of the physical and psychological scores are transformed to a score of 0 to 100 (worse state of health). A negative change from Baseline indicates improvement.

The EQ-5D is a self-administered questionnaire consisting of 5 domains pertaining to specific health state profile : mobility, self-care, usual activities, pain/discomfort and anxiety/depression. The participants recorded their level of current health for each domain where: 1=no problems, 2=some problem and 3=severe problems. The health score is derived from the individual scores for each of the 5 domains transformed to a score of 0=worst health state to 1=perfect health state. A positive change from Baseline indicates improvement.

The participant rated their current heath state using the EQ VAS 20-centimeter horizontal line from 0 (worst imaginable health state) to 100 (best imaginable health state). A positive change from baseline indicates improvement.

Heath resource utilization was assessed by the number of hospitalizations, emergency room visits, and unscheduled neurologist visits for MS-related and non-MS-related visits.

Heath resource utilization was assessed by the number of hospitalizations, emergency room visits, and unscheduled neurologist visits for MS-related and non-MS-related visits.

Participants answered the question: "How satisfied or dissatisfied are you with the ability of the medication to prevent or treat the condition?" using the following scale: Dissatisfied (Extremely dissatisfied, Very dissatisfied, Dissatisfied) or Satisfied (Somewhat satisfied, Satisfied, Very Satisfied and Extremely satisfied). The number of participants in the Dissatisfied and Satisfied categories is reported.

The HRPQ was used by the participant to assess the impact of MS or its treatments on employment. The participant recorded their scheduled work hours. Data is reported by part time or full time employment.

The HRPQ was used by the participant to assess the impact of MS or its treatments on employment. The participant recorded whether their MS or its treatments caused them to miss work. Data is reported by part time or full time employment.

The HRPQ was used by the participant to assess the impact of MS or its treatments on employment. The participant recorded the hours they missed work due to MS or its treatments. Data is reported by part time or full time employment.

The HRPQ was used by the participant to assess the impact of MS or its treatments on employment. The participants assessed the percent impact of MS and its treatments on their work output using a VAS where 0= MS or its treatments had no impact on how much I accomplished to 100=MS or its treatments kept me from accomplishing anything. Data is reported for part time or full time employment.

The HRPQ was used by the participant to assess the impact of MS or its treatments on performing household chores. The participant recorded their planned hours for household chores.

The HRPQ was used by the participant to assess the impact of MS or its treatments on performing household chores. The participant recorded whether MS or its treatments kept them from completing household chores.

The HRPQ was used by the participant to assess the impact of MS or its treatments on performing household chores. The participant recorded the hours where they were not able to perform household chores due to MS or its treatments.

The HRPQ was used by the participant to assess the impact of MS or its treatments on performing household chores. The participant assessed the percent impact of MS and its treatments on how much they accomplished using a VAS where 0= MS or its treatments had no impact on how much I accomplished to 100=MS or its treatments kept me from accomplishing anything.

Clinical Laboratory assessments included tests of hematology, blood chemistry, renal function, and thyroid function. The investigator determined if the results were clinically significant.

The VAS is a 10 cm-long horizontal line labeled with 2 extremes of pain at either end: 0 =no pain on the left and 100=very painful on the right. The participant rates their perceived pain of each injection by placing a vertical mark on the line to indicate the level of pain.

The investigator assessed the injection site after the first dose and before the fourth dose for the presence of erythema (None, Mild, Moderate, Severe), pigmentation (None, Hypo, Hyper), Induration (None, Mild, Moderate, Severe), Tenderness (None, Mild, Moderate, Severe) and Temperature (Normal, Warm, Hot). The number of participants in each grade is reported.

Blood samples were collected for ADAbs and were analyzed using a laboratory test. The number of participants ADAb positive at any post-baseline timepoint is reported.

Blood samples were collected for NAbs and were analyzed using a laboratory test. The number of participants NAb positive at any post-baseline timepoint is reported.

SDMT is a screening test for cognitive impairment. Participants are given 90 seconds in which to pair specific numbers with given geometric figures using a key. Scores range from 0 to 110 (best). A positive change from baseline indicates improvement.

SDMT is a screening test for cognitive impairment. Participants are given 90 seconds in which to pair specific numbers with given geometric figures using a key. Scores range from 0 to 110 (best). A positive change from baseline indicates improvement.

The PASAT 3 assesses auditory information processing speed. A random series of numbers from 1 to 9, inclusive, are presented and the participant is instructed to consecutively add pairs of numbers so that each number is added to the one that immediately preceded it. In the 3- second PASAT, numbers are presented at a rate of 1 every 3 seconds. The total possible score is the number of correct responses from 0 to 60 (best). A positive change from baseline indicates improvement.

The PASAT 3 assesses auditory information processing speed. A random series of numbers from 1 to 9, inclusive, are presented and the participant is instructed to consecutively add pairs of numbers so that each number is added to the one that immediately preceded it. In the 3- second PASAT, numbers are presented at a rate of 1 every 3 seconds. The total possible score is the number of correct responses from 0 to 60 (best). A positive change from baseline indicates improvement.