Upadacitinib (UPA), a selective JAK-1 inhibitor, is a new therapeutic option, the use of which for the treatment of patients with rheumatoid arthritis (RA) according to international randomized clinical trials (RCTs) [10–16] allows patients with insufficient effect of therapy with DMARDs or biologics achieve therapy goals fairly quickly. This evidence concerns the gene JAK1 and rheumatoid arthritis.