Preventive Effect of Clopidogrel on the Systemic Sclerosis Development Risk

Inclusion Criteria: * Patient over 18 years old, and less than 85 years old. * Patient with positive AAN (AAN ≥ 1/160) with the following specificity: anti-Scl70 or anti-centromere or anti-RNApolIII, or any other auto-antibodies related to systemic sclerosis * Patient with RP reported by the subject and confirmed by the physician. * Patient affiliated to a health insurance system. * Patient who accepts to participate to the study and signs an inform consent form. Exclusion Criteria: * Patient with an SSc diagnosis according to ACR/EULAR 2013 criteria. * Patient with skin fibrosis at screening. * Patient with antiplatelet treatment at screening. * Patient with contraindications to clopidogrel. * Patient treated by immunosuppressive agent at screening. * Patient treated by anticoagulants at screening * Pregnant or breastfeeding women. * Women of childbearing age refusing effective contraception method during the study treatment (24 months). * Incompetent adults (i.e. Individuals under the protection of a conservator)