Safety and Efficacy Study of RXIM002 in Severe, Relapsed or Refractory Autoimmune Diseases

Inclusion Criteria: * Subjects voluntary agreement to provide written informed consent. * Aged 18 to 65 years, either sex. * Adequate organ function meeting screening criteria. * Positive test for cluster of differentiation antigen 19 (CD19). Systemic Lupus Erythematosus (SLE) and Lupus Nephritis (LN): * Have been diagnosed with SLE or LN before screening. * Presence of anti-dsDNA, anti-histone, anti-chromatin, anti-Ro (anti-SS-A), anti-La (anti-SS-B), antinuclear antibody (ANA), or anti-Sm antibodies at screening. * Active disease at screening. * Fulfill relapsed/refractory SLE or LN conditions Lupus Nephritis (LN) : * Kidney biopsy result indicating LN * Evidence of LN disease activity Systemic Sclerosis (SSc): * Have been diagnosed with SSc before screening. * Antinuclear Antibody (ANA) positive at screening or prior to screening. AND, evidence of SSc disease activity. * Fulfill relapsed/refractory SSc conditions. Immune Thrombocytopenia (ITP): * Have been diagnosed with refractory ITP before screening. * Platelet count \<50×10⁹/L at screening. Idiopathic Inflammatory Myopathy (IIM): * Have been diagnosed with IIM before screening. * Presence of at least 1 myositis specific (MSA), associated antibody (MAA), or ANA at screening or prior to screening. * Evidence of IIM disease activity. * Fulfill relapsed/refractory IIM conditions. Membranous Nephropathy (MN): * Have been diagnosed with MN before screening. * Active MN patients meeting screening criteria. * Fulf…