Efficacy and Safety Study of Abatacept to Treat Lupus Nephritis

Number of participants achieving CR was divided by total participants in that arm, expressed as a percentage. CR is defined the following criteria: eGFR is normal or no <85% of the baseline value; eGFR is based on mean creatinine value from day 358 and 365. Proteinuria: UPCR<0.5 mg/mg. Urine sediment: No cellular casts. Corticosteroid dose: Daily dose must be no >10 mg prednisone or equivalent for at least 28 days prior. Subjects with >10mg/day prednisone or equivalent for non-renal disease within 28 days prior to day 365 will be imputed as CR if the following are true: Met all criteria for CR at day 337 and all criteria for CR except corticosteroid dose at day 365; Investigator confirms increase in steroid dose is not related to renal disease. Adjusted odds ratio is estimated from logistic regression model which includes treatment group, baseline ACEi/ARBs use, race and baseline UPCR as a continuous variable.

Adjusted Mean Change from Baseline in UPCR at Day 365 of the double-blind period in nephrotic participants

Adjusted Mean Change from Baseline in Urine protein/creatinine ratio (UPCR) at Day 365 of the double-blind period in the overall population

Adjusted mean change from baseline in British Isles Lupus Assessment Group (BILAG) score over time during Year 1 of the double-blind period based on a repeated measure mixed model and presented at each visit in the first 12-month of the double-blind period. BILAG index measures disease activity in different organs/systems separately. BILAG score is calculated for each of 9 systems depending on the clinical features present and whether they are new (4 points), worse (3 points), the same (2 points), improving (1 point) or not present (0 points) in the last 4 weeks compared with previously. BILAG "A" represents the presence of serious features of lupus. BILAG "B" represents more moderate features of the disease. BILAG "C" includes only mild symptomatic features. BILAG "D" represents prior activity with no current symptoms due to active lupus. BILAG "E" represents an organ that has never been involved. Overall BILAG score ranges from 0-108, with higher scores reflecting a worse outcome.

All AEs were coded and grouped into preferred terms (PT) by system organ class (SOC), using the Medical Dictionary for Regulatory Activities (MedDRA, version 21.0). Investigators determined the intensity of each AE as mild, moderate, severe, or very severe and assessed the relationship to study drug.

Complete Renal Response or Complete Response (CR): defined as meeting ALL of the following criteria: eGFR normal OR no less than 85% of the baseline value; UPCR < 0.5; Urine sediment: No cellular casts; Daily corticosteroid dose must be no greater than 10 mg prednisone or equivalent for at least 28 days prior to assessment. Partial Renal Response or Partial Response (PR): defined as meeting ALL of the following criteria: Participant does not meet criteria for CR; eGFR no less than 85% of the lesser of the values at screening or randomization (Day 1); UPCR < 0.5 OR 50% reduced from baseline and < 1 if baseline value was < 3, OR 50% reduced from baseline and < 3 if baseline value was greater than or equal to 3; Urine sediment: no cellular casts; daily corticosteroid dose no greater than 10 mg/day prednisone or prednisone equivalent for at least 28 days prior to assessment. No Renal Response or No Response (NR): defined as not meeting criteria for CR or PR or withdrawn

The estimate of median time to Complete Renal Response is based on Kaplan-Meier analysis. Complete renal response (CR): defined as meeting ALL of the following criteria: eGFR normal OR no less than 85% of the baseline value; Urine protein/creatinine ratio (UPCR) < 0.5; Urine sediment: No cellular casts; Daily corticosteroid dose must be no greater than 10 mg prednisone or equivalent for at least 28 days prior to assessment.

The estimate of median time to Complete Renal Response in nephrotic participants is based on Kaplan-Meier analysis. Complete renal response (CR): defined as meeting ALL of the following criteria: eGFR normal OR no less than 85% of the baseline value; Urine protein/creatinine ratio (UPCR) < 0.5; Urine sediment: No cellular casts; Daily corticosteroid dose must be no greater than 10 mg prednisone or equivalent for at least 28 days prior to assessment.

The estimate of median time to Partial Response (PR) is based on Kaplan-Meier analysis. Partial renal response (PR): defined as meeting ALL of the following criteria: Participant does not meet criteria for CR; eGFR no less than 85% of the lesser of the values at screening or randomization (Day 1); UPCR < 0.5 OR 50% reduced from baseline and < 1 if baseline value was < 3, OR 50% reduced from baseline and < 3 if baseline value was 3; Urine sediment: no cellular casts; daily corticosteroid dose no greater than 10 mg/day prednisone or prednisone equivalent for at least 28 days prior to assessment

The estimate of median time to Partial Response (PR) in nephrotic participants is based on Kaplan-Meier analysis. Partial renal response (PR): defined as meeting ALL of the following criteria: Participant does not meet criteria for CR; eGFR no less than 85% of the lesser of the values at screening or randomization (Day 1); UPCR < 0.5 OR 50% reduced from baseline and < 1 if baseline value was < 3, OR 50% reduced from baseline and < 3 if baseline value was 3; Urine sediment: no cellular casts; daily corticosteroid dose no greater than 10 mg/day prednisone or prednisone equivalent for at least 28 days prior to assessment

A repeated measure mixed model that included the baseline UPCR value, randomization stratification factors, time, and time by treatment interaction as fixed effects and subject as a random effect was used.

A repeated measure mixed model that included the baseline UPCR value, randomization stratification factors, time, and time by treatment interaction as fixed effects and subject as a random effect was used.

% Change from Baseline = (post baseline - baseline value) / baseline value x 100

Estimated glomerular filtration rate(eGFR), will be calculated by the CKD-EPI formula shown below.50 eGFR is expressed as mL/min per 1.73m2. For the purpose of this study lower limit of normal eGFR is defined as 90mL/min per 1.73m2 eGFR = 141 X min (Scr/k, 1)α X max (Scr/k, 1)-1.209 X 0.993Age X (1.018 [if female]) X (1.159 [if black]) Where Scr is serum creatinine (mg/dL), k is 0.7 for females and 0.9 for males, α is -0.329 for females and -0.411 for males, min indicates the minimum of Scr/k or 1, and max indicates the maximum of Scr/k or 1, age in years.

Sustained response defined as response present at 2 consecutive visits approximately 4 weeks apart. No renal response (NR): defined as not meeting criteria for CR or PR or withdrawn

The estimate of median time is based on Kaplan-Meier analysis

Sustained change to no response is defined as going from CR (or PR) to NR and remaining in NR for at least 2 consecutive visits; visits should be approximately 4 weeks apart. This analysis will be based on time from response CR (or PR) to the first visit in which the no response (NR) was achieved and sustained to the next visit.

BILAG index measures and reports disease activity in different organs/systems separately. The BILAG score is calculated for each of nine systems depending on the clinical features present and whether they are new (4 points), worse (3 points), the same (2 points), improving (1 point) or not present (0 points) in the last 4 weeks compared with previously. A BILAG "A" represents the presence of one or more serious features of lupus. A BILAG "B" represents more moderate features of the disease. A BILAG "C" includes only mild symptomatic features. A BILAG "D" represents only prior activity with no current symptoms due to active lupus. A BILAG "E" represents an organ that has never been involved. Overall BILAG score ranges from 0-108, with higher scores reflecting a worse outcome.

Trough level serum concentration of abatacept prior to the administration of the IV infusion on Days 1 to 365

Cmax: Maximum observed serum concentration following participants receiving active abatacept IV

AUC (TAU): Area under the serum concentration time curve over a dosing interval between Days 337 to 365.

Summary statistics for systolic blood pressure

Summary statistics for diastolic blood pressure

Summary statistics for Heart Rate

Laboratory assessments were analyzed centrally, with the exception of pregnancy testing. Blood draws and urine collections were performed at visits specified in the protocol.

Change from Baseline = Post-baseline - Baseline value.

Laboratory assessments were analyzed centrally, with the exception of pregnancy testing. Blood draws and urine collections were performed at visits specified in the protocol.

Change from Baseline = Post-baseline - Baseline value.

Laboratory assessments were analyzed centrally, with the exception of pregnancy testing. Blood draws and urine collections were performed at visits specified in the protocol.

Change from Baseline = Post-baseline - Baseline value.

Laboratory assessments were analyzed centrally, with the exception of pregnancy testing. Blood draws and urine collections were performed at visits specified in the protocol.

Change from Baseline = Post-baseline - Baseline value.

Laboratory assessments were analyzed centrally, with the exception of pregnancy testing. Blood draws and urine collections were performed at visits specified in the protocol.

Change from Baseline = Post-baseline - Baseline value.

Laboratory assessments were analyzed centrally, with the exception of pregnancy testing. Blood draws and urine collections were performed at visits specified in the protocol.

Change from Baseline = Post-baseline - Baseline value.

LLN= Lower limit of normals ULN= Upper limit of normals Pre RX = Baseline value HEMOGLOBIN g/L 4.0 HB >3 G/DL DECREASE FROM PRE RX HEMATOCRIT vol 6.3 HCT <0.75X PRE RX ERYTHROCYTES x10*12 c/L 5.2 RBC <0.75X PRE RX PLATELET COUNT x10*9 c/L 5.0 PLAT <0.67X LLN OR >1.5X ULN, OR IF PRE RX<LLN THEN USE 0.5X PRE RX AND <100,000/MM3 LEUKOCYTES x10*9 c/L 6.2 WBC <0.75X LLN OR >1.25X ULN, OR IF PRE RX<LLN THEN USE <0.8X PRE RX OR >ULN, OR IF PRE RX>ULN THEN USE >1.2X PRE RX OR <LLN EOSINOPHILS (ABSOLUTE) x10*9 c/L 8.3 EOSA IF VALUE > .750 X10*3 c/uL BASOPHILS (ABSOLUTE) x10*9 c/L 8.3 BASOA IF VALUE > 400/MM3 MONOCYTES (ABSOLUTE) x10*9 c/L 8.3 MONOA IF VALUE > 2000/MM3 LYMPHOCYTES (ABSOLUTE) x10*9 c/L 8.3 LYMPA IF VALUE < .750 X10*3 c/uL OR IF VALUE > 7.50 X10*3 c/uL

N = the number of participants with at least 1 on treatment lab result for each analyte

LLN= Lower limit of normals ULN= Upper limit of normals Pre RX = Baseline value ALKALINE PHOSPHATASE (ALP) U/L 5.0 ALP >2X ULN, OR IF PRE RX>ULN THEN USE >3X PRE RX ASPARTATE AMINOTRANSFERASE (AST) U/L 5.0 AST >3X ULN, OR IF PRE RX>ULN THEN USE >4X PRE RX ALANINE AMINOTRANSFERASE (ALT) U/L 5.0 ALT >3X ULN, OR IF PRE RX>ULN THEN USE >4X PRE RX G-GLUTAMYL TRANSFERASE (GGT) U/L 5.0 GGT >2X ULN, OR IF PRE RX>ULN THEN USE >3X PRE RX BILIRUBIN, TOTAL umol/L 5.1 TBILI >2X ULN, OR IF PRE RX>ULN THEN USE >4X PRE RX BILIRUBIN, DIRECT umol/L 5.1 DBILI >1.5X ULN, OR IF PRE RX>ULN THEN USE >2X PRE RX BLOOD UREA NITROGEN mmol/L 5.1 BUN >2X PRE RX CREATININE umol/L 5.0 CREAT >1.5X PRE RX

N = the number of participants with at least 1 on treatment lab result for each analyte

LLN= Lower limit of normals ULN= Upper limit of normals Pre RX = Baseline value SODIUM, SERUM mmol/L 4.0 NA <0.95X LLN OR >1.05X ULN, OR IF PRE RX<LLN THEN USE <0.95X PRE RX OR >ULN, OR IF PRE RX>ULN THEN USE >1.05X PRE RX OR <LLN POTASSIUM, SERUM mmol/L 4.1 K <0.9X LLN OR >1.1X ULN, OR IF PRE RX<LLN THEN USE <0.9X PRE RX OR >ULN, OR IF PRE RX>ULN THEN USE >1.1X PRE RX OR <LLN CHLORIDE, SERUM mmol/L 5.0 CL <0.9X LLN OR >1.1X ULN, OR IF PRE RX<LLN THEN USE <0.9X PRE RX OR >ULN, OR IF PRE RX>ULN THEN USE >1.1X PRE RX OR <LLN

N = the number of participants with at least 1 on treatment lab result for each analyte

LLN= Lower limit of normals ULN= Upper limit of normals Pre RX = Baseline value PROTEIN, URINE Unknown UPRO IF MISSING PRE THEN USE >=2, OR IF VALUE >=4, OR IF PRE RX =0 OR 0.5 THEN USE >=2, OR IF PRE RX =1 THEN USE >=3, OR IF PRE RX =2 OR 3 THEN USE >=4 GLUCOSE, URINE N/A UGLU IF MISSING PRE THEN USE >=2, OR IF VALUE >=4, OR IF PRE RX =0 OR 0.5 THEN USE >=2, OR IF PRE RX =1 THEN USE >=3, OR IF PRE RX =2 OR 3 THEN USE >=4 BLOOD, URINE N/A UBLD IF MISSING PRE THEN USE >=2, OR IF VALUE >=4, OR IF PRE RX =0 OR 0.5 THEN USE >=2, OR IF PRE RX =1 THEN USE >=3, OR IF PRE RX =2 OR 3 THEN USE >=4 RBC, URINE hpf 5.0 URBC IF MISSING PRE THEN USE >=2, OR IF VALUE >=4, OR IF PRE RX =0 OR 0.5 THEN USE >=2, OR IF PRE RX =1 THEN USE >=3, OR IF PRE RX =2 OR 3 THEN USE >=4 WBC, URINE hpf 5.0 UWBC IF MISSING PRE THEN USE >=2, OR IF VALUE >=4, OR IF PRE RX =0 OR 0.5 THEN USE >=2, OR IF PRE RX =1 THEN USE >=3, OR IF PRE RX =2 OR 3 THEN USE >=4

LLN= Lower limit of normals ULN= Upper limit of normals Pre RX = Baseline value CALCIUM, TOTAL mmol/L 5.2 CA <0.8X LLN OR >1.2X ULN, OR IF PRE RX<LLN THEN USE <0.75X PRE RX OR >ULN, OR IF PRE RX>ULN THEN USE >1.25X PRE RX OR <LLN PHOSPHORUS, INORGANIC mmol/L 5.2 PHOS <0.75X LLN OR >1.25X ULN, OR IF PRE RX<LLN THEN USE <0.67X PRE RX OR >ULN GLUCOSE, SERUM mmol/L 4.1 GLUC <65 mg/dL, OR >220 mg/dL PROTEIN, TOTAL g/L 5.0 TPRO <0.9X LLN OR >1.1X ULN, OR IF PRE RX<LLN THEN USE 0.9X PRE RX OR >ULN, OR IF PRE RX>ULN THEN USE 1.1X PRE RX OR <LLN ALBUMIN g/L 3.0 ALB <0.9X LLN, OR IF PRE RX<LLN THEN USE <0.75X PRE RX CHOLESTEROL, TOTAL (TC) mmol/L 5.2 CHOL >2X PRE R

N = the number of participants with at least 1 on treatment lab result for each analyte

All AEs were coded and grouped into preferred terms (PT) by system organ class (SOC), using the Medical Dictionary for Regulatory Activities (MedDRA, version 21.0). Investigators determined the intensity of each AE as mild, moderate, severe, or very severe and assessed the relationship to study drug.

Lupus treatment failure is defined as any of the following: Death, unless due to physical trauma or violence; Renal Flare; sustained doubling of creatinine from baseline (greater of Screening or Study Day 1 value); initiation of rescue therapy for treatment of active lupus nephritis after Study Week 20.

Overall treatment failure is defined as lupus treatment failure plus discontinuation of study drug for any reason except death due to physical trauma or violence, pregnancy or administrative decision by Sponsor.

First treatment failure (or Lupus treatment failure) is defined as any of the following: Death, unless due to physical trauma or violence; Renal Flare; sustained doubling of creatinine from baseline (greater of Screening or Study Day 1 value); initiation of rescue therapy for treatment of active lupus nephritis after Study Week 20.

Overall treatment failure is defined as lupus treatment failure plus discontinuation of study drug for any reason except death due to physical trauma or violence, pregnancy or administrative decision by Sponsor.

The hazard ratio is estimated using the Cox proportional hazards model which includes treatment group, stratification variables (baseline ACEis/ARBs use, RACE) and baseline UPCR.

The estimate of median time is based on Kaplan-Meier analysis

Number of participants achieving CR was divided by total participants in that arm, expressed as a percentage. CR is defined the following criteria: eGFR is normal or no <85% of the baseline value; eGFR is based on mean creatinine value from day 358 and 365. Proteinuria: UPCR<0.5 mg/mg. Urine sediment: No cellular casts. Corticosteroid dose: Daily dose must be no >10 mg prednisone or equivalent for at least 28 days prior. Subjects with >10mg/day prednisone or equivalent for non-renal disease within 28 days prior to day 365 will be imputed as CR if the following are true: Met all criteria for CR at day 337 and all criteria for CR except corticosteroid dose at day 365; Investigator confirms increase in steroid dose is not related to renal disease. Adjusted odds ratio is estimated from logistic regression model which includes treatment group, baseline ACEi/ARBs use, race and baseline UPCR as a continuous variable.

Number of participants achieving CR was divided by total participants in that arm, expressed as a percentage. CR is defined the following criteria: eGFR is normal or no <85% of the baseline value; eGFR is based on mean creatinine value from day 358 and 365. Proteinuria: UPCR<0.5 mg/mg. Urine sediment: No cellular casts. Corticosteroid dose: Daily dose must be no >10 mg prednisone or equivalent for at least 28 days prior. Subjects with >10mg/day prednisone or equivalent for non-renal disease within 28 days prior to day 365 will be imputed as CR if the following are true: Met all criteria for CR at day 337 and all criteria for CR except corticosteroid dose at day 365; Investigator confirms increase in steroid dose is not related to renal disease. Adjusted odds ratio is estimated from logistic regression model which includes treatment group, baseline ACEi/ARBs use, race and baseline UPCR as a continuous variable.

LLN= Lower limit of normals ULN= Upper limit of normals Pre RX = Baseline value HEMOGLOBIN g/L 4.0 HB >3 G/DL DECREASE FROM PRE RX HEMATOCRIT vol 6.3 HCT <0.75X PRE RX ERYTHROCYTES x10*12 c/L 5.2 RBC <0.75X PRE RX PLATELET COUNT x10*9 c/L 5.0 PLAT <0.67X LLN OR >1.5X ULN, OR IF PRE RX<LLN THEN USE 0.5X PRE RX AND <100,000/MM3 LEUKOCYTES x10*9 c/L 6.2 WBC <0.75X LLN OR >1.25X ULN, OR IF PRE RX<LLN THEN USE <0.8X PRE RX OR >ULN, OR IF PRE RX>ULN THEN USE >1.2X PRE RX OR <LLN EOSINOPHILS (ABSOLUTE) x10*9 c/L 8.3 EOSA IF VALUE > .750 X10*3 c/uL BASOPHILS (ABSOLUTE) x10*9 c/L 8.3 BASOA IF VALUE > 400/MM3 MONOCYTES (ABSOLUTE) x10*9 c/L 8.3 MONOA IF VALUE > 2000/MM3 LYMPHOCYTES (ABSOLUTE) x10*9 c/L 8.3 LYMPA IF VALUE < .750 X10*3 c/uL OR IF VALUE > 7.50 X10*3 c/uL

N = the number of participants with at least 1 on treatment lab result for each analyte

LLN= Lower limit of normals ULN= Upper limit of normals Pre RX = Baseline value ALKALINE PHOSPHATASE (ALP) U/L 5.0 ALP >2X ULN, OR IF PRE RX>ULN THEN USE >3X PRE RX ASPARTATE AMINOTRANSFERASE (AST) U/L 5.0 AST >3X ULN, OR IF PRE RX>ULN THEN USE >4X PRE RX ALANINE AMINOTRANSFERASE (ALT) U/L 5.0 ALT >3X ULN, OR IF PRE RX>ULN THEN USE >4X PRE RX G-GLUTAMYL TRANSFERASE (GGT) U/L 5.0 GGT >2X ULN, OR IF PRE RX>ULN THEN USE >3X PRE RX BILIRUBIN, TOTAL umol/L 5.1 TBILI >2X ULN, OR IF PRE RX>ULN THEN USE >4X PRE RX BILIRUBIN, DIRECT umol/L 5.1 DBILI >1.5X ULN, OR IF PRE RX>ULN THEN USE >2X PRE RX BLOOD UREA NITROGEN mmol/L 5.1 BUN >2X PRE RX CREATININE umol/L 5.0 CREAT >1.5X PRE RX

N = the number of participants with at least 1 on treatment lab result for each analyte

LLN= Lower limit of normals ULN= Upper limit of normals Pre RX = Baseline value SODIUM, SERUM mmol/L 4.0 NA <0.95X LLN OR >1.05X ULN, OR IF PRE RX<LLN THEN USE <0.95X PRE RX OR >ULN, OR IF PRE RX>ULN THEN USE >1.05X PRE RX OR <LLN POTASSIUM, SERUM mmol/L 4.1 K <0.9X LLN OR >1.1X ULN, OR IF PRE RX<LLN THEN USE <0.9X PRE RX OR >ULN, OR IF PRE RX>ULN THEN USE >1.1X PRE RX OR <LLN CHLORIDE, SERUM mmol/L 5.0 CL <0.9X LLN OR >1.1X ULN, OR IF PRE RX<LLN THEN USE <0.9X PRE RX OR >ULN, OR IF PRE RX>ULN THEN USE >1.1X PRE RX OR <LLN

N = the number of participants with at least 1 on treatment lab result for each analyte

LLN= Lower limit of normals ULN= Upper limit of normals Pre RX = Baseline value PROTEIN, URINE Unknown UPRO IF MISSING PRE THEN USE >=2, OR IF VALUE >=4, OR IF PRE RX =0 OR 0.5 THEN USE >=2, OR IF PRE RX =1 THEN USE >=3, OR IF PRE RX =2 OR 3 THEN USE >=4 GLUCOSE, URINE N/A UGLU IF MISSING PRE THEN USE >=2, OR IF VALUE >=4, OR IF PRE RX =0 OR 0.5 THEN USE >=2, OR IF PRE RX =1 THEN USE >=3, OR IF PRE RX =2 OR 3 THEN USE >=4 BLOOD, URINE N/A UBLD IF MISSING PRE THEN USE >=2, OR IF VALUE >=4, OR IF PRE RX =0 OR 0.5 THEN USE >=2, OR IF PRE RX =1 THEN USE >=3, OR IF PRE RX =2 OR 3 THEN USE >=4 RBC, URINE hpf 5.0 URBC IF MISSING PRE THEN USE >=2, OR IF VALUE >=4, OR IF PRE RX =0 OR 0.5 THEN USE >=2, OR IF PRE RX =1 THEN USE >=3, OR IF PRE RX =2 OR 3 THEN USE >=4 WBC, URINE hpf 5.0 UWBC IF MISSING PRE THEN USE >=2, OR IF VALUE >=4, OR IF PRE RX =0 OR 0.5 THEN USE >=2, OR IF PRE RX =1 THEN USE >=3, OR IF PRE RX =2 OR 3 THEN USE >=4

LLN= Lower limit of normals ULN= Upper limit of normals Pre RX = Baseline value CALCIUM, TOTAL mmol/L 5.2 CA <0.8X LLN OR >1.2X ULN, OR IF PRE RX<LLN THEN USE <0.75X PRE RX OR >ULN, OR IF PRE RX>ULN THEN USE >1.25X PRE RX OR <LLN PHOSPHORUS, INORGANIC mmol/L 5.2 PHOS <0.75X LLN OR >1.25X ULN, OR IF PRE RX<LLN THEN USE <0.67X PRE RX OR >ULN GLUCOSE, SERUM mmol/L 4.1 GLUC <65 mg/dL, OR >220 mg/dL PROTEIN, TOTAL g/L 5.0 TPRO <0.9X LLN OR >1.1X ULN, OR IF PRE RX<LLN THEN USE 0.9X PRE RX OR >ULN, OR IF PRE RX>ULN THEN USE 1.1X PRE RX OR <LLN ALBUMIN g/L 3.0 ALB <0.9X LLN, OR IF PRE RX<LLN THEN USE <0.75X PRE RX CHOLESTEROL, TOTAL (TC) mmol/L 5.2 CHOL >2X PRE R

N = the number of participants with at least 1 on treatment lab result for each analyte

Participants who experienced a positive antibody response relative to baseline (ECL Assay)