The Reduction of Systemic Lupus Erythematosus Flares :Study PLUS

Inclusion Criteria: * Age of 18 and above * Diagnosis of Systemic Lupus Erythematosus (SLE) according to the American College of Rheumatology (ACR) Classification Criteria. * Treatment with HCQ for at least 6 months, without modification of HCQ dosage for 2 months * Stable dosage of HCQ from one day to another (200 g x 2/day or 400 mg once a day or 200 mg once a day) * No increase in the steroids dosage during the 3 previous weeks * Steroids dosage lower or equal to 0. 5 mg/kg/day of prednisone equivalent * No modifications of a possible immunosuppressor during the 2 previous months * SELENA-SLEDAI \< or = 12 * Signature of the consent of participation Exclusion Criteria: * Known retinopathy, present or passed * Severe cataract obstructing the ophthalmologic monitoring * MONOPHTALM patients * Past history of intolerance with HCQ (in particular gastro-intestinal, or retinal) during the possible former use of a higher dosage * Use of nivaquine during the 3 previous months * Treatment with biotherapy (for example Rituximab) during the 12 previous months * Calculated clearance of creatinin lower than 60 ml/min * Chronic alcoholism * Liver failure * Desire of pregnancy in the next 7 months * Known non compliance, and risks of random follow-up * Absence of social security cover People profiting from a particular protection: * Pregnant women * Age under 18 * Patient under supervision and TRUSTEESHIP * People who are hospitalized without their consent and not protected by the law * People who are private of freedom. Criteria of inclusion at the visit of randomization (D0): All the patients responding to the next criterions can be randomized: * Blood HCQ concentration ranging between 100 and 750 ng/ml at the time of the visit of preselection, * No increase in the steroids dosage since last visit * No modifications of a possible immunosuppressor since last visit * SELENA-SLEDAI \< or = 12 Activity of the lupus remaining stable (no increase of more than 2 points of the SELENA-SLEDAI), * Ophthalmologic examination in the 6 previous months with no contra-indication for the use of HCQ, * Absences of conductive disorders on the ECG * Use of an effective contraception, * Negative Beta-HCG.