Safety and Tolerability of IBI355 in Patients With Primary Sjogren's Syndrome

Inclusion criteria

• Understand and sign the informed consent form;
• Age ≥ 18 years, male or female；
• Body Mass Index (BMI) within the range of 18.0 to 28.0 kg/m² (inclusive);
• Meet the 2016 American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) classification criteria for Sjögren's Syndrome;
• Positive for anti-Sjögren's syndrome A autoantibodies (SSA) and/or anti-Sjögren's syndrome B autoantibodies (SSB);
• Unstimulated whole salivary flow rate > 0 ml/min;

Exclusion criteria

• Individuals who have had allergic reactions to any components of IBI355, have allergic diseases, or possess an allergic constitution;
• Those who cannot tolerate frequent venipuncture procedures;
• Participants diagnosed with secondary Sjögren's syndrome, or whose clinical symptoms (or laboratory abnormalities) require explanation by another connective tissue disease (such as systemic lupus erythematosus, mixed connective tissue disease, etc.).
• Subjects paticipated in the other clinical trail in 1 month or less than 5 t1/2 since the previous clinical trial (which is longer)；
• Subjects with an infection requiring systemic medication was present within 30 days prior to randomization;
• HIV-Ab、RPR、HCV-Ab、HBV、HBeAg or HBcAb, one of them positive;
• There have a clinical or imaging evidence that the subject with active tuberculosis, or there is evidence that the subject is in the incubation period for tuberculosis;

6.Patients with a history of central nervous system, cardiovascular system, digestive system, respiratory system, urinary system, blood system, metabolic disorders and other systemic diseases; 7. Subject with a hcg positive; 8.Patients with a history of neuropsychiatry or who are considered unfit to participate in this clinical trial; 9.Patients with pulmonary interstitial fibrosis, or those requiring combined antifibrotic drug therapy, or those with abnormal lung function that the investigators determined was not suitable for this study; 10. Need to use other drugs that could cause xerostomia during the study.