Janus kinase (JAK) inhibitors are a new class of molecules available to the therapeutic arsenal for chronic inflammatory rheumatic diseases.The tolerance profile of this new class needs to be better defined and its use in real life further established.

The French Society of Rheumatologists intends to coordinate a prospective national registry study for this follow-up.

This registry will include at least 1500 Rheumatoid Arthritis (RA) and 150 patients with psoriatic arthritis from the start of treatment with JAK inhibitor and then followed for 5 years.

This registry is a longitudinal, multicentre, observational registry study. The objective of this national registry is to get a better understanding of the safety profiles of JAK inhibitors and get knowledge of their use in daily practice in order to optimize this use and potentially integrate JAK inhibitors into personalised medicine strategies.

This registry will generate efficacy data, especially therapeutic maintenance, observation, allowing inter-registry comparisons with other biologic compounds in the French population, and can be aggregated with other similar registries in other countries.

Design:

This registry is a longitudinal, multicentre, observational registry study, with continuous and ambispective collection of clinical and laboratory data. The patients will be followed for 5 years, regardless of the therapeutic modifications occurring thereafter.

Target population:

Patients initiating JAK inhibitor therapy for inflammatory rheumatic disorder.

Number of patients and centres :

• The objective is to include, per drug available on the market, at least 300 to 500 patients with RA and at least 100 to 150 patients with psoriatic arthritis. If a JAK inhibitor is approved in a new indication of chronic rheumatic disease by European Medicines Agency (EMA), the number of patients to include for each molecule in this indication will be adjusted as a function of the prevalence/epidemiology of each disease. Products currently available (baricitinib and tofacitinib) will be considered at the start of this registry; then every new indication for an already approved drug or every new drug in the same therapeutic class starting from the date they are placed on the market will be considered.
• More than 80 centers in France (hospital-based, public and private practice) will participate.

Inclusion criteria

• Patients older than 18
• Patient treated with a JAK inhibitor in accordance with EMA, for chronic inflammatory rheumatisms, independent of the therapeutic line
• Subject who is a member of a social security regime
• Free, declared, written consent signed by the subject and the investigator on the day of inclusion Exclusion criteria
• Patient who cannot understand the implications and rules of the study
• Patient opposition to participating in the study

French patients treated for chronic inflammatory rheumatic disorders according to EMA.