Sarcoidosis is a systemic granulomatosis of unknown etiology with almost systematic pulmonary involvement. The reference treatment for pulmonary sarcoidosis is prolonged systemic corticosteroid therapy, which improves dyspnea, fatigue and respiratory function. However, corticosteroid therapy doesn't improve quality of life, possibly due to its adverse effects, which are dose- and time-dependent, such as weight gain, diabetes, insomnia, hypertension. Furthermore, in an international survey study, the first priority in treatment outcome for sarcoidosis patient was quality of life. Recent optimizations have reduced the attack treatment duration from 3 to 1 month, but with a persistence of adverse effects appearing in the first months.~Hydroxychloroquine is an antimalarial drug, used for systemic lupus erythematosus with a very good benefit/risk ratio and low cost, but also for rheumatoid arthritis. Its anti-inflammatory effects involve inhibition of antigenic presentation, chemotaxis, phagocytosis, lymphocyte proliferation, cytokine production (e.g TNFα), or Toll-like receptors expression. These immunological mechanisms are also involved in the pathogenesis of sarcoidosis. In addition, Hydroxychloroquine decreases the risk of developing diabetes mellitus, dyslipidemia or thrombotic events. Hydroxychloroquine has been shown to be effective in cutaneous and pulmonary forms of sarcoidosis, and in hypercalcemia, but in studies with imperfect methodology. Baltzan et al. showed that a maintenance treatment of hydroxychloroquine versus placebo reduced the risk of relapse and lung function decline in pulmonary sarcoidosis. Our hypothesis is that hydroxychloroquine associated with low-dose corticosteroids improves lung function as much as conventional medium-dose corticosteroid therapy but with fewer side effects and a better quality of life in pulmonary sarcoidosis. The main objective is to demonstrate the non-inferiority of the combination of hydroxychloroquine and low-dose corticosteroids versus medium-dose corticosteroid therapy on the improvement of respiratory function at 6 months.~The secondary objectives are to (i) demonstrate the superiority of the combination of hydroxychloroquine and low-dose corticosteroids versus medium-dose corticosteroid therapy at 3, 6 months and 1 year on general quality of life, respiratory quality of life, fatigue, adverse drug event, treatment compliance and (ii) demonstrate the non-inferiority of the combination of hydroxychloroquine and low-dose corticosteroids versus medium-dose corticosteroid therapy at 3, 6 months and 1 year on : respiratory function using complementary tools, respiratory symptoms, and activity of thoracic and extra-thoracic sarcoidosis. 
The reference treatment for pulmonary sarcoidosis is prolonged systemic corticosteroid therapy, which improves dyspnea, fatigue and respiratory function. However, corticosteroid therapy doesn't improve quality of life, possibly due to its adverse effects. Furthermore, in an international survey study, the first priority in treatment outcome for sarcoidosis patient was quality of life.~Hydroxychloroquine an antimalarial drug, has been shown to be effective in cutaneous and pulmonary forms of sarcoidosis but in studies with imperfect methodology. Our hypothesis is that hydroxychloroquine associated with low-dose corticosteroids improves lung function as much as conventional medium-dose corticosteroid therapy but with fewer side effects and a better quality of life in pulmonary sarcoidosis. 