Rheumatoid arthritis (RA) is the most common inflammatory joint disorder. Since twenty year and the use of synthetic disease-modifying anti-rheumatic drugs (csDMARDs) and biological (b)DMARD, remission can be reached. When remission is obtained, the physician has no recommendations for managing a step-down, and future guidelines will be useful to assist the clinician. Recent data suggest that tapering is feasible, but with high risk of flares. Flares are less frequent when bDMARD blood concentration is high. But, the optimal adalimumab concentration to keep before a step of tapering no targeting personal is unknown.

Inclusion Criteria:

• Patient over 18 years of age
• Patients with a diagnosis of RA according to ACR/EULAR 2010 criteria
• Remission according to DAS28<=2.6 for at least 6 months
• Patient treated with ADA for at least 6 months. The patient is treated according to one of the following two strategies:
• ADA 40 mg every two weeks (= every 14 days) according to the standard regimen
• or ADA 40 mg every 3 weeks (= every 21 days)
• A negative highly sensitive pregnancy test for women of Childbearing Potential*
• Affiliated person or beneficiary of a social security scheme
• Informed consent signed by the patient after information

Exclusion Criteria:

• Incapacity or refusal to understand and / or sign informed consent to participate in the study.
• Existing pregnancy, lactation, or intended pregnancy within the next 15 months
• Fibromyalgia associated to RA
• Any dose of prednisone for RA treatment 6 months before inclusion
• Patient deprived of liberty or patient under guardianship or curator ship.