Table 2.

In-Vitro Study of QS Against SARS-CoV-2

Cells	Type of Virus	Result	Reference
Vero B4 cells	The virus strain SARS-CoV-2 PR1	Quinine exerts antiviral activity against SARS-CoV-2 that at 10 μM was even stronger than that of HCQ or CQ. With 10μM QS viral replication can be reduced by 90%, while HCQ is only reduced by 50%	[6]
Vero B4 cells	The virus strain SARS-CoV-2 PR1	Quinine exerts antiviral activity against SARS-CoV-2 that at 10 μM was even stronger than that of HCQ or CQ. With 10μM QS viral replication can be reduced by 90%, while HCQ is only reduced by 50%	[34]
TMPRSS2+ Human Colon Cells	The recombinant SARS-CoV-2 infectious clone, icSARS-CoV-2-mNG, expressing mNeonGreen as a reporter gene	Quinine treatment in doses of 50 μM and above inhibited SARS-CoV-2 infection at this high MOI setting nearly completely, with a with a dose dependent effect down to 2 μM
Human Transgenic Lung Cancer Cells	The virus strain SARS-CoV-2 PR1	Quinine exhibits antiviral activity against SARS-CoV-2 in A549 lung cancer cell lines and that its antiviral activity might be modulated but not abrogated by the expression of TMPRSS2
Calu-3 lung cell	icSARS-CoV-2 mNG	Quinine excerted antiviral activity with IC50 27 μM
Vero E6 cells	SARS-CoV-2 strain (IHUMI-3)	Quinine showed medium antiviral in vitro activity with EC50 of 10.7 ± 3.0 µM and EC90 of 38.8 ± 34 µM	[35]

Abbreviation: TMPRSS2+, Transmembrane Serine Protease 2; MOI, Multiplicity of Infection; IC, Inhibition Concentration; EC, Effective Concentration.