TMPRSS2 and infection: It is relevant to highlight that bromhexine has been initially identified as a potent inhibitor (IC50 = 0.75 μM) of the transmembrane serine protease 2 (TMPRSS2) of SARS-CoV [5], being involved also in the binding and infection (mainly via a non-endocytotic route) of SARS-CoV-2 to host cells [7].