Clinical Study of CD19/CD20 tanCAR T Cells in Relapsed and/or Refractory AQP4-IgG Seropositive Neuromyelitis Optica Spectrum Disorders (NMOSD)

This study is being conducted to assess anti-CD19/20 CAR T cells safety and efficacy in treating patients with AQP4-IgG seropositive NMOSD. PRIMARY OBJECTIVES: I. To assess the safety of the tanCART-19/20 cells in treating NMOSD patients. II. Determine duration of in vivo survival of tanCART-19/20 cells. SECONDARY OBJECTIVES: I. To assess the efficacy of the tanCART-19/20 cells in treating NMOSD patients. II. The secondary outcome measures: annual relapse rate (ARR), Expanded Disability Status Scale Score(EDDS), Best Corrected Visual Acuity (Log MAR), Spectral-Domain Optical Coherence Tomography (SD-OCT), Flash Visual Evoked Potential (FVEP) and Immunological assessments. OUTLINE: Patients receive anti-CD19/20-CAR (coupled with CD137 and CD3 zeta signalling domains) vector-transduced autologous T cells on days 0 in the absence of unacceptable toxicity. The infusion dose is 1E5-2E6 CAR positive T cells/kg, and dose escalation methods obey the traditional 3+3 design (three doses groups: 1-2E5, 3-6E5, 1-2E6 CAR-T cells). After completion of study treatment, patients are followed intensively for 6 months, every 6 months for 2 years, and annually thereafter for 3 years.