In cell culture, Bi1 effectively inhibited virus reproduction with an EC50 of 5.9 μM, and a (low) cytotoxicity CC50 of 5 mM.173 qRT-PCR studies showed that Bi1 inhibits the replicative cycle of SARS-CoV-1.173 These data suggest that the efficacy of Bi1 may be due to inhibition of SARS-CoV-1 helicase, which possesses >99.5% sequence similarity to the helicase of SARS-CoV-2.174 Potassium bismuth citrate is currently on clinical trial for treatment of COVID-19 (Trial ChiCTR2000030398 in Wuhan), as well as the zinc ionophore hydroxychloroquine (IRCT20100228003449N28; IRCT20100228003449N29).175. Here, TMBIM6 is linked to COVID-19.