The Safety and Efficacy of Telitacicept in the Treatment of Systemic Sclerosis

Inclusion Criteria: 1. Subjects with systemic sclerosis who met the ACR2013 classification criteria for systemic sclerosis and approved this trial 2. Age: 18 years or older 3. Lung function FVC% \> 50% 4. Positive for ANA or scleroderma related autoantibodies 5. Patients with disease activity after conventional treatment: new skin involvement or deterioration of two new body areas or skin thickening and deterioration after 6 months of conventional treatment (δMRSS ≥0 points) 6. The dose of the following drugs was stable for at least 6 months before the first use of the study drug: mycophenolate mofetil, cyclophosphamide；First use of study drug precorticosteroids (≤10 mg prednisone/day or equivalent) for at least 30 days Exclusion Criteria: 1. Subjects who did not consent to participate in the clinical trial 2. Subjects with mixed connective tissue disease or overlap syndrome 3. Focal scleroderma 4. Pregnant women, lactating women and men or women who have planned to have children in the last 12 month 5. Allergic reaction: History of allergy to human derived biological products 6. Participants who had participated in any clinical trial within 28 days prior to initial screening/or within a 5-fold half-life of the study compound (whichever is longer) 7. Those who have received live vaccine in the last month 8. B cell-targeted therapies such as rituximab, iparizumab, and beliumab were used within one year 9. Tumor necrosis factor inhibitors and interleukin-receptor blockers were used within one year. 10. Patients who used intravenous gamma globulin (IVIG), prednisone ≧100 mg/d for more than 14 days within one month or underwent plasma exchange surgery 11. Use Chinese medicine for treatment within one month 12. There is active infection (such as herpes zoster, HIV infection, active tuberculosis, etc.) during the screening period 13. There are serious complications such as uncontrolled congestive heart failure, arrhythmias, severe pulmonary hypertension or hypertension, severe gastrointestinal involvement, liver function impairment, active infection, severe diabetes mellitus, atherosclerotic heart disease, malignancy, AIDS, or severe peripheral vascular disease. 14. Patients with severe depression, psychosis or suicidal ideation