Inclusion Criteria:

Participants eligible for inclusion in this study must meet all of the following criteria:

- Adult male and female participants aged 18 years or older at the time of baseline.

-Weigh at least 35 kg at screening.

Have a confirmed clinical diagnosis of SLE according to European League Against Rheumatism/American College of Rheumatology (EULAR/ACR) Systemic lupus erythematosus (SLE) classification criteria.

Have a positive anti-nuclear antibody (ANA) test result; ANA titer ≥ 1:80 at screening visit
based on central laboratory result.

Active LN at screening, as defined by meeting the 3 following criteria:

- Biopsy within 6 months prior to screening period indicating ISN/RPS class III or IV
active glomerulonephritis with or without co-existing class V features, or pure class
V membranous LN. If no biopsy was performed within 6 months prior to screening period,
a biopsy will need to be performed during the screening period after having met all
other inclusion/exclusion criteria.

- UPCR ≥ 1.0 on 24h urine collection at Screening.

- eGFR ≥ 25mL/min/1.73 m^2.

Participants must be currently on, or willing to initiate SoC induction therapy for LN
according to the institutional practices using MPA

Receipt of at least one dose of pulse methylprednisolone i.v. (500-1000 mg) or equivalent
for treatment of current episode of active LN during past 60 days prior screening.

Able to communicate well with the Investigator to understand and comply with the
requirements of the study.

Exclusion Criteria:

Participants meeting any of the following criteria are not eligible for inclusion in this
study.

Severe renal impairment as defined by i.) Stage 4 Chronic Kidney Disease (CKD), or ii.)
presence of oliguria (defined as a documented urine volume < 400 mL/24 hrs), or iii.)
End-Stage Renal Disease (ESRD) requiring dialysis or transplantation.

Sclerosis in > 50% of glomeruli on renal biopsy.

Use of other investigational drugs within 5 half-lives of enrollment, or within 30 days or
until the expected pharmacodynamic effect has returned to baseline.

Prior use of any B cell depleting therapy within 36 weeks prior to randomization or as long
as B cell count < 50 cells/µL.

Prior treatment with any of the following within 12 weeks prior to randomization:

- belimumab, abatacept, TNF-α mAb, immunoglobulins (i.v./s.c.) plasmapheresis;

- any other immuno-suppressants (i.v. or oral cyclophosphamide, calcineurin inhibitors,
JAK inhibitors or other kinase inhibitors);

- thalidomide treatment and/or one of the following DMARDs: methotrexate or an imidazole
derivative (e.g., azathioprine, mizoribine).

Receipt of more than 3000 mg i.v. pulse methylprednisolone (cumulative dose) within 12
weeks prior to Baseline.

History of major organ transplant or hematopoietic stem cell/bone marrow transplant or are
due to receive transplantation.

Any one of the following laboratory values at screening:

- Hemoglobin levels < 8.0 g/dL;

- Platelet count < 75 x 1000/µL;

- Absolute neutrophil count (ANC) < 1.0 x 1000/µL;

Active viral, bacterial or other infections requiring systemic treatment at the time of
screening, or history of recurrent clinically significant infection or of bacterial
infections with encapsulated organisms.

History of known intolerance/hypersensitivity to MPA, oral corticosteroids, or any
component of the study drug(s) or its excipients.

Receipt of live/attenuated vaccine within a 4-week period prior to randomization.

History of primary or secondary immunodeficiency, including a positive HIV test result.

History of malignancy of any organ system (other than localized basal cell carcinoma or
squamous cell carcinoma of the skin or or in-situ cervical cancer), treated or untreated,
within the past 5 years, regardless of whether there is evidence of local recurrence or
metastases.

Any surgical, medical (e.g., uncontrolled hypertension, heart failure or diabetes),
psychiatric or additional physical condition that the Investigator feels may jeopardize the
patient in case of participation in this study.

Chronic infection with hepatitis B (HBV) or hepatitis C (HCV). Positive serology for
hepatitis B surface antigen (HBsAg) excludes the participant.

Evidence of active tuberculosis (TB) infection (after anti-TB treatment, participants with
history of TB may become eligible according to national guidelines).

Pregnant or nursing (lactating) women.

Women of child-bearing potential, defined as all women physiologically capable of becoming
pregnant, unless they are using highly effective methods of contraception during dosing and
for 6 months after stopping of investigational medication.

Eligibility last updated 10/10/22. Questions regarding updates should be directed to the study team contact.