CW8001 is a covalent Exportin-1 (XPO1) inhibitor with an EC50 value of 1 nM for inhibiting T cell activation. It prevents the nuclear localization of NFAT transcription factors, thereby suppressing the expression of inflammatory cytokines like IL-2. CW8001 shows potential for research in T cell-driven immune diseases such as graft-versus-host disease (GVHD).