A Study of Rapcabtagene Autoleucel in Active, Refractory Systemic Lupus Erythematosus (SLE) or Lupus Nephritis (LN) Patients (AUTOGRAPH - SLE/LN)

Key Who May Qualify: - Men and women with SLE, aged \>= 18 years and =\< 75 years at screening, fulfilling the 2019 European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) classification criteria for SLE at screening. - Participant must be positive for at least one of the following autoantibodies at screening: antinuclear antibodies (ANA) at a titer of \>= 1:80 (on HEp-2 cells or an equivalent positive test), or anti-dsDNA (above the ULN); or anti-Sm (above the ULN) as determined by a central laboratory. - Active lupus nephritis without signs of significant chronicity or active systemic lupus erythematosus - SLEDAI-2K Criteria at screening: SLEDAI-2K score \>= 6 points (Gladman et al 2002, Touma et al 2011), excluding points attributed to "fever", "lupus headache", "alopecia", and "organic brain syndrome". - Inadequate response at screening to at least two therapies Key Who Should NOT Join This Trial: - Any acute, severe lupus related-flare at screening that needs immediate treatment other than pulse GCs and/or makes the immunosuppressive washout impossible and, thus, makes the participant ineligible for CD19 CAR-T therapy - Inyour organs (liver, kidneys, etc.) are working well enough based on blood tests during screening and prior to randomization - History or current diagnosis of ECG or cardiac abnormalities indicating significant risk of safety for participants prior to randomization - Human weakened immune system virus (HIV) positivity at screening. - Acute or chronic infection with hepatitis B (HBV) or hepatitis C (HCV) at screening. - Grade 2 or higher thromboembolic event in the past 4 weeks prior to screening. Other protocol-defined inclusion/exclusion criteria may apply. Always talk to your doctor about whether this trial is right for you.