Janus kinase (JAK) is a family of intracellular, non-receptor tyrosine kinases that transduce cytokine-mediated signals via the JAK-STAT pathway. They were initially named "just another kinase" 1 and 2, but were ultimately published as "Janus kinase". The name is taken from the two-faced Roman god of beginnings, endings and duality, Janus, because the JAKs possess two near-identical phosphate-transferring domains. One domain exhibits the kinase activity, while the other negatively regulates the kinase activity of the first.
The JAK-STAT signaling pathway is a chain of interactions between proteins in a cell, and is involved in processes such as immunity, cell division, cell death, and tumour formation. The pathway communicates information from chemical signals outside of a cell to the cell nucleus, resulting in the activation of genes through the process of transcription. There are three key parts of JAK-STAT signalling: Janus kinases (JAKs), signal transducer and activator of transcription proteins (STATs), and receptors. Disrupted JAK-STAT signalling may lead to a variety of diseases, such as skin conditions, cancers, and disorders affecting the immune system.
Non-receptor tyrosine-protein kinase TYK2 is an enzyme that in humans is encoded by the TYK2 gene.
Tyrosine-protein kinase JAK3 is a tyrosine kinase enzyme that in humans is encoded by the JAK3 gene.
14-3-3 protein eta also referred to as 14-3-3η is a protein that in humans is encoded by the YWHAH gene.
John J. O'Shea is an American physician and immunologist.
A Janus kinase inhibitor, also known as JAK inhibitor or jakinib, is a type of immune modulating medication, which inhibits the activity of one or more of the Janus kinase family of enzymes, thereby interfering with the JAK-STAT signaling pathway in lymphocytes.
JAK3 deficiency is a dysfunction in cytokine receptor signalling and their production of cytokines.
Tofacitinib, sold under the brand Xeljanz among others, is a medication used to treat rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, polyarticular course juvenile idiopathic arthritis, and ulcerative colitis. It is a janus kinase (JAK) inhibitor, discovered and developed by the National Institutes of Health and Pfizer.
Ruxolitinib, sold under the brand name Jakafi among others, is a medication used for the treatment of intermediate or high-risk myelofibrosis, a type of myeloproliferative neoplasm that affects the bone marrow; polycythemia vera, when there has been an inadequate response to or intolerance of hydroxyurea; and steroid-refractory acute graft-versus-host disease. Ruxolitinib is a Janus kinase inhibitor. It was developed and marketed by Incyte Corp in the US under the brand name Jakafi, and by Novartis elsewhere in the world, under the brand name Jakavi.
Fedratinib, sold under the brand name Inrebic, is an anti-cancer medication used to treat myeloproliferative diseases including myelofibrosis. It is used in the form of fedratinib hydrochloride capsules that are taken by mouth. It is a semi-selective inhibitor of Janus kinase 2 (JAK-2). It was approved by the FDA on 16 August 2019.
Baricitinib, sold under the brand name Olumiant among others, is an immunomodulatory medication used for the treatment of rheumatoid arthritis, alopecia areata, and COVID-19. It acts as an inhibitor of janus kinase (JAK), blocking the subtypes JAK1 and JAK2.
Filgotinib, sold under the brand name Jyseleca, is a medication used for the treatment of rheumatoid arthritis (RA). It was developed by the Belgian-Dutch biotech company Galapagos NV.
Peficitinib is a pharmaceutical drug used for the treatment of rheumatoid arthritis. It belongs to the class of drugs known as Janus kinase inhibitors.
Upadacitinib, sold under the brand name Rinvoq, is a medication used for the treatment of rheumatoid arthritis, psoriatic arthritis, atopic dermatitis, ulcerative colitis, Crohn's disease, ankylosing spondylitis, and axial spondyloarthritis. Upadacitinib is a Janus kinase (JAK) inhibitor that works by blocking the action of enzymes called Janus kinases. These enzymes are involved in setting up processes that lead to inflammation, and blocking their effect brings inflammation in the joints under control.
Janus kinase 3 inhibitors, also called JAK3 inhibitors, are a new class of immunomodulatory agents that inhibit Janus kinase 3. They are used for the treatment of autoimmune diseases. The Janus kinases are a family of four nonreceptor tyrosine-protein kinases, JAK1, JAK2, JAK3, and TYK2. They signal via the JAK/STAT pathway, which is important in regulating the immune system. Expression of JAK3 is largely restricted to lymphocytes, while the others are ubiquitously expressed, so selective targeting of JAK3 over the other JAK isozymes is attractive as a possible treatment of autoimmune diseases.
WAY-204688, also known as SIM-688, is a synthetic nonsteroidal estrogen and nuclear factor κB (NF-κB) inhibitor which was originated by ArQule and Wyeth and was under development by Wyeth for the treatment of rheumatoid arthritis, non-specific inflammation, and sepsis but was never marketed. It is a "pathway-selective" estrogen receptor (ER) ligand which inhibits NF-κB with an IC50Tooltip half-maximal inhibitory concentration of 122 nM and with maximal inhibition relative to estradiol of 94%. Inhibition of NF-κB by WAY-204688 appears to be dependent on agonism of the ERα, as it is reversed by the ERα antagonist fulvestrant, but is not dependent on the ERβ. In contrast to the case of NF-κB inhibition, WAY-204688 produces only slight elevation of creatine kinase in vitro, a measure of classical estradiol effects. It reached phase I clinical trials prior to the discontinuation of its development.
An antiarthritic is any drug used to relieve or prevent arthritic symptoms, such as joint pain or joint stiffness. Depending on the antiarthritic drug class, it is used for managing pain, reducing inflammation or acting as an immunosuppressant. These drugs are typically given orally, topically or through administration by injection. The choice of antiarthritic medication is often determined by the nature of arthritis, the severity of symptoms as well as other factors, such as the tolerability of side effects.
Z583 (GLXC-26150) is a chemical compound which acts as a potent and highly selective inhibitor of JAK3, and was developed for the treatment of rheumatoid arthritis.
Pamapimod is an investigational drug which is being evaluated for the treatment of autoimmune diseases. It is a p38 mitogen-activated protein kinase inhibitor. It has been evaluated in a phase 2 clinical trial for the treatment of rheumatoid arthritis, but was found not to be effective. It has subsequently been investigated as a possible treatment for osteoarthritis.
