The clinical trials (Malet-Martino and Martino, 2002) from 1994 of the aurofin compound (2,3,4,6-tetra-O-acetyl-b-1-D-thipyranosato-S-(triphenylphosphine)gold(I)) initially used in the treatment of rheumatoid arthritis (Mirzadeh et al., 2019) revealed new ways of inhibiting cysteine (Cys), seleno-cysteine (Sec), glutathione reductase (GR), mitochondrial thioredoxin reductase (TrxR2), and cytosolic thioredoxin reductase (TrxR1) and opened new paths in the design of new monodentate phosphine precursors. The gene discussed is GSR; the disease is rheumatoid arthritis.