The BILAG Index measures clinical disease activity in Systemic Lupus Erythematosus (SLE). A single alphabetic score (A through E) is used to denote disease severity for each of the 8 domains. The global BILAG score is the sum of a converted numerical score (A=9, B=3, C=1, D=0, E=0) over 8 domains. MCR = participants who achieved BILAG C scores or better at 24 weeks, maintained this response without developing a flare to 52 weeks, and did not experience a severe flare from Day 1 to Week 24; PCR = participants who achieved BILAG C score or better at 24 wks and maintained response without a flare for 16 consecutive weeks, or maximum of one BILAG B score at 24 weeks and maintained response without a flare to 52 wks, or maximum of 2 BILAG B scores at 24 wks without development of BILAG scores of A or B until Week 52 if the baseline BILAG score was 1A+>=2Bs, or>=2 As, or>=4 Bs, or participants who enrolled with scores of severe disease and did not achieve a single BILAG B at Month 6.

Intent-to-treat (ITT) population

The BILAG Index measures clinical disease activity in SLE. A single alphabetic score (A through E) is used to denote disease severity for each of the 8 domains. The global BILAG score is the sum of a converted numerical score (A=9, B=3, C=1, D=0, E=0) over 8 domains. The AUCMB of BILAG Score Over 52 Weeks was calculated as: 1. Calculate the AUC of the BILAG global score versus time (in days) by 52 weeks. 2. Calculate the Time-Adjusted AUC by dividing the AUC by the number of days a patient was on the study. 3. Minus the Time-Adjusted AUC by the baseline BILAG global score

ITT population

The BILAG Index measures clinical disease activity in SLE. A single alphabetic score (A through E) is used to denote disease severity for each of the 8 domains. The global BILAG score is the sum of a converted numerical score (A=9, B=3, C=1, D=0, E=0) over 8 domains. MCR = participants who achieved BILAG C scores or better at 24 weeks, maintained this response without developing a flare to 52 weeks, and did not experience a severe flare from Day 1 to Week 24. PCR = participants who achieved BILAG C score or better at 24 wks and maintained response without a flare for 16 consecutive weeks, or maximum of one BILAG B score at 24 weeks and maintained response without a flare to 52 wks, or maximum of 2 BILAG B scores at 24 wks without development of BILAG scores of A or B until Week 52 if the baseline BILAG score was 1A+>=2Bs, or>=2 As, or>=4 Bs, or participants who enrolled with scores of severe disease and did not achieve a single BILAG B at Month 6.

ITT population

The BILAG Index measures clinical disease activity in SLE. A single alphabetic score (A through E) is used to denote disease severity for each of the 8 domains. The global BILAG score is the sum of a converted numerical score (A=9, B=3, C=1, D=0, E=0) over 8 domains. PCR = participants who achieved BILAG C score or better at 24 wks and maintained response without a flare for 16 consecutive weeks, or maximum of one BILAG B score at 24 weeks and maintained response without a flare to 52 wks, or maximum of 2 BILAG B scores at 24 wks without development of BILAG scores of A or B until Week 52 if the baseline BILAG score was 1A+>=2Bs, or>=2 As, or>=4 Bs, or participants who enrolled with scores of severe disease and did not achieve a single BILAG B at Month 6. MCR = participants who achieved BILAG C or better at 24 weeks, maintained this response without developing a flare to 52 weeks, and did not experience a severe flare from Day 1 to Week 24.

ITT population

The BILAG Index measures clinical disease activity in SLE. A single alphabetic score (A through E) is used to denote disease severity for each of the 8 domains. The global BILAG score is the sum of a converted numerical score (A=9, B=3, C=1, D=0, E=0) over 8 domains.

ITT population

The BILAG Index measures clinical disease activity in SLE. A single alphabetic score (A through E) is used to denote disease severity for each of the 8 domains. The global BILAG score is the sum of a converted numerical score (A=9, B=3, C=1, D=0, E=0) over 8 domains. A severe flare = participants had BILAG A score(s) present in one or more domains or BILAG B scores present in three or more domains at the same visit following a visit of inactive disease state defined above. A moderate flare = participants had only BILAG B scores present in two domains at the same visit following a visit of inactive disease state.

Number of participants who ever reached C/D/E for all 8 BILAG domains before Day 364 visit. If a participant reached C/D/E at the last visit, then this participant was excluded from the analysis.

Short Form (36) with additional questions specific to lupus (scale = 0-100; with 100 representing the highest level of functioning possible) to measure the ability of rituximab to improve quality of life. A positive value for this outcome measure indicates that symptoms have improved.

ITT population

The BILAG Index measures clinical disease activity in SLE. A single alphabetic score (A through E) is used to denote disease severity for each of the 8 domains. The global BILAG score is the sum of a converted numerical score (A=9, B=3, C=1, D=0, E=0) over 8 domains. MCR = participants who achieved BILAG C scores or better at 24 weeks, maintained this response without developing a flare to 52 weeks, and did not experience a severe flare from Day 1 to Week 24.

ITT population