Blocking TLR4 can lower CCR1 and CCR2 expression both of which are lower level immune control receptors. It would also have some control over downregulation of inflammatory cytokines but there are other factors that can call them up so it's far from absolute.

Meanwhile CCL5 (RANTES) controls the TLR4 upregulation of cytokine expression. So leronlimab would effectively block that.

EDSA is basing it's move to phase 3 from interim analysis on a small number of patients taken off ECMO. Which is the right move to accelerate to a trial that could result in an EUA. But results may not prove out in a larger trial.