Immunosuppressant; JAK1/2 inhibitor; NAK inhibitor. Significantly improved COVID-19 symptoms in preliminary human trial, possibly through attenuation of viral entry via inhibition of NAK kinases. Cantini et al. J. Infect., Apr 23 2020, https://dx.doi.org/10.1016%2Fj.jinf.2020.04.017; Spinelli et al. Sci. Immunol., 5:eabc5367, May 2020, https://doi.org/10.1126/sciimmunol.abc5367.
Biochemicals & reagents
1) JS Fridman et al. J. Immunol. 2010 184:5298 2) S Kubo et al. Front. Immunol. 2018 9:1510 3) F Cantini et al. J. Infect. 2020 April 23, DOI: 10.1016/j.jinf.2020.04.017
Baricitinib is approved by the FDA for two inflammatory disorders, rheumatoid arthritis and alopecia areata and selectively inhibits Janus kinase 1 (IC50 = 5.9 nM) and 2 (5.7 nM), over 3 (0.56 µM) (1). This compound thereby blocks JAK/STAT signaling, reducing cytokine release and suppressing the innate and adaptive immune systems (1,2) and was recently shown to significantly improve COVID-19 symptoms in a preliminary human trial, presumably through suppression of the cytokine release syndrome (“cytokine storm”) induced by SARS-CoV-2 infection (3).