New generations of small molecules are being developed for the treatment of ulcerative colitis. Among them, tofatinib (a Janus kinase (JAK) inhibitor) has demonstrated efficacy for inducing and maintaining remission and achieving mucosal healing with a reasonable safety profile. Oral administration is attractive for patients and lack of immunogenicity represents an advantage over biologic drugs. Areas covered: This review discusses the molecular aspects of the JAK-STAT pathway; the mechanism of action of tofacitinib pertinent to ulcerative colitis and the evidence on the efficacy of tofacitinib for achieving clinically relevant outcomes, including clinical remission, mucosal healing, and normalization of quality of life, as well as safety aspects with special attention to adverse events related to the mode of action of the drug. Expert commentary: Tofacitinib will be the first drug on the class of JAK inhibitors to be available for treatment of ulcerative colitis. The efficacy of the drug, with a rapid onset of action even in cases of severe colitis, oral administration, and possibility to use the drug intermittently without generating immunogenicity, will bring about a redesign of current treatment paradigms for ulcerative colitis.
Keywords: Inflammatory bowel disease; Janus-kinase inhibitor; safety; signal transducer and activator of transcription; tofacitinib; ulcerative colitis.