A Phase 1 Study of HB2198 in Participants With Moderately to Severely Active Systemic Lupus Erythematosus (SLE)

Inclusion Criteria: * • Meet 2019 ACR / 2023 EULAR SLE classification criteria * Moderate or high disease activity (SLEDAI 2K ≥6; PGA ≥1) * LN participants: biopsy confirmed active Class III/IV ± V or Class V LN; proteinuria ≥0.8 g/g; eGFR ≥30 mL/min/1.73 m² * ERL participants: inadequate response/intolerance to ≥1 standard SLE therapy * Positive ANA (≥1:80) or SLE associated autoantibodies * Required minimum lab values (lymphocytes ≥500/µL, B cells ≥25/µL, ANC ≥1000/mm³, IgG ≥600 mg/dL, etc.) * Women of childbearing potential: negative pregnancy test; contraception required * Voluntary informed consent Exclusion Criteria: * (Key) Inclusion Criteria: * Meet 2019 ACR / 2023 EULAR SLE classification criteria * Moderate or high disease activity (SLEDAI 2K ≥6; PGA ≥1) * LN participants: biopsy confirmed active Class III/IV ± V or Class V LN; proteinuria ≥0.8 g/g; eGFR ≥30 mL/min/1.73 m² * ERL participants: inadequate response/intolerance to ≥1 standard SLE therapy * Positive ANA (≥1:80) or SLE associated autoantibodies * Required minimum lab values (lymphocytes ≥500/µL, B cells ≥25/µL, ANC ≥1000/mm³, IgG ≥600 mg/dL, etc.) * Women of childbearing potential: negative pregnancy test; contraception required * Voluntary informed consent (Key) Exclusion Criteria: * Anti CD19 or anti CD20 therapy within 6 months * Active CNS lupus * Significant cardiovascular, pulmonary, hepatic, or uncontrolled systemic disease * Active infection or recent serious infection * Positive HBV DNA or HCV RNA; HIV infection * Major surgery within 4 weeks * Prior organ or stem cell transplant * Current pregnancy or breastfeeding * Recent IVIg or plasmapheresis (\<3 months) * Live vaccine within 30 days * Any condition judged unsuitable by Investigator