Carefully consider patients w/ active, chronic or recurrent infections prior to initiating therapy. Temporarily interrupt treatment & monitor patients if an infection, herpes zoster, DVT or pulmonary embolism (PE) develops. Screen patients for TB prior to starting therapy. Do not administer in patients w/ active TB. Consider anti-TB therapy prior to initiation of therapy in patients w/ previously untreated latent TB. Observe patients w/ absolute neutrophil count <1 x 109
cells/L, absolute lymphocyte count <0.5 x 109
cells/L & Hb <8 g/dL & temporarily interrupt treatment; risk of lymphocytosis may increase in elderly patients w/ RA. Perform screening for viral hepatitis in accordance w/ clinical guidelines prior to initiation of therapy. Monitor for HBV DNA expression in patients w/ hepatitis B surface Ab & hepatitis B core Ab w/o hepatitis B surface antigen. Concomitant use w/ live, attenuated vaccines during or immediately prior to therapy is not recommended. Assess lipid parameters approx 12 wk following initiation of therapy. Temporarily interrupt treatment until drug-induced liver injury is excluded & if alanine transaminase (ALT) or aspartate transaminase (AST) elevations occur. May increase risk of malignancies eg, lymphoma. Patients w/ risk factors for DVT/PE (eg, older age, obesity, medical history of DVT/PE & those undergoing surgery or immobilisation). Concomitant use w/ biologic DMARDs or other Janus kinase (JAK) inhibitors, & potent immunosuppressive drugs (eg, azathioprine, tacrolimus, ciclosporin). May decrease female fertility during treatment. Women of childbearing potential must use effective contraception during & for at least 1 wk after treatment. Lactation.