Bromhexine is a cough medication, available over-the-counter in much of the world, that has been proposed as a COVID-19 therapeutic.
Potential mechanism of action
Bromhexine has been speculated to inhibit the TMPRSS2 serine protease used by SARS-CoV-2.
In an August 6th, 2020 NIH paper, bromhexine did not directly inhibit TMPRSS2 in vitro. Study author Matt Hall noted:
"The fact bromhexine is not inhibiting TMPRSS2 doesn't mean it can't work against COVID, and other recent literature in cell models supports our data." -Matt Hall, NIH researcher
COVID-19 clinical trials
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