Pharmaceutical aspects of JAK inhibitors: a comparative review

Janus kinase inhibitors (JAKIs) are a new class of drugs used in the treatment of a heterogeneous group of diseases, mainly inflammatory and autoimmune diseases. Janus kinase (JAK) is a family of non-receptor tyrosine kinases in cells that transduce cytokine-mediated signals. JAK, along with signal transducer and activator of transcription (STAT) protein, mediate important cellular processes such as immune response, carcinogenesis, cell differentiation, cell division, and cell death. Therefore, inhibitors of JAK-STAT signaling pathways could be useful in treating conditions mediated by the above-mentioned processes. JAK inhibitors mainly treat inflammatory and/or autoimmune diseases such as rheumatoid arthritis, psoriasis, and atopic dermatitis. In this review, we tried to focus on the discovery, pharmacology, and pharmaceutical aspects of JAK inhibitor drugs and their relative risks and benefits, especially focusing on the adverse effects of this class of drugs.