The Efficacy and Safety of Iguratimod (IGU) in the Treatment of Primary Sjögren's Syndrome

Inclusion Criteria: * Diagnosed with pSS by meeting the 2016 ACR/EULAR Classification Criteria. * The patient complained of dry mouth and eyes. * Positive anti-SSA/Ro-60 antibody at screening. * IgG≥16 g/L. * No hormone, immunosuppressant, biological agents or other treatments were received within 4 weeks before screening; * Pregnancy test of is negative. Use effective contraceptives during the trial (female) * Those who did not participate in any drug trial within 12 weeks before enrollment Exclusion Criteria: * Pregnant or lactating or planning to get pregnant during the duration of the study. * Complicated with other CTD * Complicated with malignancy * mental illness, a history of alcohol abuse, immunodeficiency, uncontrolled infections, and drug or other substance abuse * serious systemic damage, glucocorticoids, other immunosuppressants and biological agents should be added to control the condition: Heart, liver (transaminase/bilirubin \>1.5 times the upper normal limit), kidney (Cr≥133mmol/L), lung (FVC % \< 60%), blood (white blood cell \<3×109/L, HGB\<80g/L, PLT\<80×109/L), etc. * Fundus/visual field lesions; * Allergic to any component of the study drug (IGU and/or HCQ); * the investigator considers the patient to be unsuitable for entry into the study