Introduction
We wish to draw attention to the possibility of repurposing the existing
calcium channel blocking drug tetrandrine for the treatment of severe
acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.
Tetrandrine is a bisbenzylisoquinoline that can be extracted from the
perennial vine plant Stephania tetrandra S. Moore (Chinese patent
WO2004009106A1, 2002), which has been used in traditional Chinese
medicine ([1], [2] and references therein). It can also be
synthesised chemically (US Patent 10,023,584 B2, 2018, [3]) .
There is extensive literature on the anti-inflammatory,
immunosuppressive, oncological and cardiovascular effects of tetrandrine
[2;4-6]. It is licensed in China for the treatment of silicosis, but
to our knowledge has not been licensed for viral illnesses in any
country to date.