In Vitro: Lalistat 1 (0-100 μM) shows activity against different non-typeable H. influenzae (NTHi) IgAP variants from clinical isolates in Elisa assay. It shows a dose-dependent inhibition of IgA1P B1 and B2, but at higher inhibitor concentrations, consistent with the higher expression levels of these variants. Nearly complete inhibition of IgA1P B1 and B2 is observed at 50 μM, with complete inhibition at 100 μM.