The design of our inhibition and infection studies allowed us to categorize the identified inhibitors as HDV entry inhibitors acting at NTCP, as (I) their binding to NTCP was demonstrated by inhibition of [3H]TC uptake and [3H]preS1-peptide binding and (II) they were only present in the infection assay for the first 6 h of HDV exposure of the NTCP-HepG2 cells, representing the early entry phase. Here, SLC10A1 is linked to infection.