Current JAK inhibitors

TargetsDrugIndication and dosageWarnings and side effects
JAK1, JAK2Baricitinib (Olumiant)Rheumatoid arthritis: oral 2 mg once dailyWarnings: Do not initiate in case of anemia < 8 g/dL, lymphopenia < 500/mm3, severe hepatic impairment, moderate or severe renal impairment
Side effects: Infectious (tuberculosis), hematologic (lymphoma), thrombosis, gastrointestinal perforation
JAK1, JAK2Ruxolitinib (Jakafi)Myelofibrosis: 5 to 20 mg orally twice daily depending on platelets count
Polycythemia vera: 10 mg orally twice daily
Acute graft-vs-host disease: 5 mg orally twice daily
Warnings: Adjustment on renal/hepatic impairment and platelet count
Side effects: Hematologic (pancytopenia, thrombocytopenia, anemia, neutropenia), infectious (herpes zoster, opportunistic infections), oncologic (non- melanoma skin cancer), metabolic (weight gain, hypercholesterolemia), other (bruising, dizziness, headaches)
JAK3 (and JAK1, JAK2)Tofacitinib (Xeljanz)Rheumatoid arthritis and psoriatic arthritis: orally, 5 mg twice daily or 11 mg once daily
Ulcerative colitis: orally, 10 mg twice daily
Warnings: Avoid in patients at increased risk of thrombosis; avoid the combination with methotrexate or other disease-modifying anti-rheumatic drug or immunosuppressant; do not initiate if lymphocytes < 500/mm3, neutrophils < 1,000/mm3, or hemoglobin < 9 g/dL; adjust on renal or hepatic impairment
Side effects: Thrombosis, infections (tuberculosis, opportunistic infections, herpes zoster), malignancy (lymphoma, skin cancer), gastrointestinal perforation, hematologic (anemia, lymphopenia, neutropenia)