IFNB1 and Castleman-Kojima disease: In July 2019, sirolimus was used to treat patients with IL-6 inhibitor-resistant iMCD.[12] Clinical trials are currently being conducted with sirolimus.[13] Langan Pai RA et al[14] noted that interferon (IFN)-β stimulation increased mTOR activation in monocytes and T cells of patients with the iMCD-TAFRO syndrome in remission, and type I IFN-induced mTOR activation in patients with the iMCD-TAFRO syndrome.