Legend discontinues the development of the IMP.

This is a prospective, single-arm, open-label, dose-exploration and expansion clinical study of LCAR-AIO in adult subjects with relapsed/refractory neurological autoimmune diseases.

This is a prospective, single-arm, open-label exploratory clinical study to evaluate the safety, tolerability, pharmacokinetics and efficacy profiles of LCAR-AIO, a chimeric antigen receptor (CAR) -T cell therapy in subjects with relapsed/refractory neurological autoimmune diseases. Patients who meet the eligibility criteria will receive LCAR-AIO infusion. The study will include the following sequential stages: screening, apheresis, pre-treatment (cell product preparation: lymphodepleting chemotherapy), treatment (LCAR AIO infusion) and follow-up.

Inclusion Criteria:

1. Subjects voluntarily participate in clinical research.
2. Age 18-70 years.
3. Adequate organ function at screening.
4. Clinical laboratory values meet criteria at screening visit.
5. Indications include:

MS;

1. Have been diagnosed of MS at least 6 months before screening.
2. Fulfill relapsed/refractory MS conditions.

NMOSD/MOGAD:

1. Have been diagnosed of NMOSD/MOGAD at least 6 months before screening.
2. AQP-4 IgG (NMOSD), or MOG-IgG (MOGAD) should be positive by CBA (Cell based transfection immunofluorescence assay).
3. Fulfill relapsed/refractory NMOSD/MOGAD conditions.

MG:

1. Have been diagnosed of MG at least 6 months before screening.
2. AChR-IgG or MuSK-IgG should be positive.
3. Fulfill relapsed/refractory NMOSD/MOGAD conditions.

Exclusion Criteria:

1. Active infections such as hepatitis and tuberculosis.
2. Other autoimmune diseases.
3. Serious underlying diseases such as tumor, uncontrolled diabetes and clinically significant cardiovascular disease.
4. Female subjects who were pregnant, breastfeeding, or planning to become pregnant while participating in this study or within 1 year of receiving LCAR-AIO treatment.