An Clinical Study of YTS109 Cell Injection in Subjects With Refractory Systemic Lupus Erythematosus

An Exploratory Clinical Study of YTS109 Cell Injection in Subjects With Refractory Systemic Lupus Erythematosus.

This study is a exploratory clinical trial in subjects with Refractory Systemic Lupus Erythematosus. The objective is to evaluate the safety, initial efficacy and PK/PD characteristics of YTS109 cells in the treatment of Refractory Systemic Lupus Erythematosus.

Eligibility Criteria:
Inclusion Criteria:

1. Age ranges from 18 to 65 years old (including threshold), regardless of gender.
2. Meet the EULAR/ACR 2019 SLE Classification Criteria Cohort 1: Refractory Lupus Nephritis Defined as failure to achieve remission after 3-6 months of treatment with ≥2 immunosuppressants (e.g., corticosteroids, CTX, tacrolimus, MMF, cyclosporine) and/or biologics, with Urine protein/creatinine ratio (UPCR ≥1.0 g/g) and renal pathology criteria:ISN/RPS 2003 Class III/IV proliferative lupus nephritis (or combined with type V features) (with ≤50% glomerulosclerosis).

Cohort 2: Refractory Thrombocytopenia

Requires treatment failure with:

Failed treatment with at least 1 course of MP shock (1g for 3 days) or high-dose glucocorticosteroids (1mg/kg/d equivalent dose of glucocorticosteroids) in combination with 1 or more mmunosuppressive agents. At least 2 consecutive routine blood tests for platelets less than 50 × 10⁹/L and \> 30 × 10\^9/L were performed prior to enrolment. other non-SLE causes of thrombocytopenia, such as infections, myelosuppression and hypersplenism, were excluded.

3.Essential Organ Function Criteria:

1. .Bone Marrow: Neutrophils ≥1×10⁹/L (within 2 weeks, excluding granulocyte colony-stimulating factor use).

   Hemoglobin ≥60 g/L.
2. .Liver: ALT/AST ≤3×ULN (disease-related elevations permitted). TBIL ≤1.5×ULN (disease-related elevations permitted).
3. .Renal: CrCl ≥30 mL/min (Cockcroft-Gault formula, excluding acute declines).
4. .Coagulation: INR/PT ≤1.5×ULN.
5. Cardiovascular: Hemodynamic stability.

4.Fertile females or males with partners of childbearing age must use medically approved contraception or abstain during and ≥12 months post-treatment.Negative serum HCG test (within 7 days pre-enrollment) for fertile females; non-lactating.

5.Voluntary participation with signed informed consent and compliance.

Exclusions:

Subjects who meet any of the following exclusion criteria will not be admitted to the study:

1. Severe drug allergies or hypersensitivity.
2. Uncontrolled/untreated infections (fungal, bacterial, viral, etc.).
3. CNS disorders (exceptions: epilepsy, psychosis, organic brain syndrome, cerebrovascular accident, encephalitis, CNS vasculitis).
4. Heart failure intolerance.
5. Congenital immunoglobulin deficiency.
6. Malignancy within 5 years (exceptions: localized cancers with negligible metastasis risk).
7. End-stage renal failure.
8. Subjects positive for:

   HBsAg / HBcAb with HBV DNA \> detection limit; HCV Ab + HCV RNA; HIV Ab; Syphilis test.
9. Deep vein thrombosis/pulmonary embolism within 6 months pre-screening.
10. Severe mental illness/cognitive impairment.
11. Participation in other clinical trials within 3 months pre-screening.
12. Use of immunosuppressants (within 5 half-lives) or biologics (within 4 weeks) pre-screening.
13. Pregnancy/breastfeeding or planned conception.
14. Other researcher-determined ineligibility.