SPTLC1 and infection: In the inhibition of pseudoviruses with single mutations, we found that LCB1 inhibited the infection of K417N mutant with IC50 of 2.774 nM on 293T/ACE2 and 4.898 nM on Huh-7 cells, which indicated 45-fold or 67-fold resistance changes over D614G reference (Figures 2C,D).