JAK1 and rheumatoid arthritis: In July 2021, the FDA issued the Emergency Use Authorization (EUA) for Eli Lilly's Janus kinase 1 and Janus kinase 2 (JAK1 and JAK2) inhibitor baricitinib (Olumiant®) as monotherapy, which is already approved for severe rheumatoid arthritis (Jorgensen et al., 2020; US FDA, 2022).