Chloroquine and Hydroxychloroquine as Available Weapons to Fight COVID-19
Colson et al., Int J. Antimicrob Agents, doi: 10.1016/j.ijantimicag.2020.105932. Epub 2020 Mar 4. (Review)
Colson et al., Chloroquine and Hydroxychloroquine as Available Weapons to Fight COVID-19, Int J. Antimicrob Agents, doi: 10.1016/j.ijantimicag.2020.105932. Epub 2020 Mar 4. (Review)
Recommending CQ and HCQ for COVID-19 based on 20 clinical studies in China and a strong rationale for use.
Colson et al., 4 Mar 2020, peer-reviewed, 5 authors.
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International Journal of Antimicrobial Agents 55 (2020) 105932
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Hot Topic
Chloroquine and hydroxychloroquine as available weapons to fight
COVID-19
Repositioning of drugs for use as antiviral treatments is a critical need [1]. It is commonly very badly perceived by virologists, as
we experienced when reporting the effectiveness of azithromycin
for Zika virus [2]. A response has come from China to the respiratory disease caused by the new coronavirus (SARS-CoV-2) that
emerged in December 2019 in this country. Indeed, following the
very recent publication of results showing the in vitro activity of
chloroquine against SARS-CoV-2 [3], data have been reported on
the efficacy of this drug in patients with SARS-CoV-2-related pneumonia (named COVID-19) at different levels of severity [4,5]. Thus,
following the in vitro results, 20 clinical studies were launched in
several Chinese hospitals. The first results obtained from more than
Table 1
Main results of studies on the activity of chloroquine or hydroxychloroquine on coronavirusesa
Reference
Compound(s)
Targeted virus
System used for antiviral activity
screening
[12]
Chloroquine
SARS-CoV
[16]
[17]
Chloroquine
Chloroquine,
chloroquine
monophosphate,
chloroquine
diphosphate
Vero
E6
Vero
Vero
SARS-CoV (four
strains)
(African green monkey kidney)
cells
E6 cells
76 cells
BALB/c mice
[18]
Chloroquine, hydroxychloroquine
SARS-CoV
Vero cells
Feline coronavirus
Crandell–Reese feline kidney (CRFK)
cells
Human epithelial lung cells (L132)
[19]
Chloroquine
HCoV-229E
[20]
Chloroquine
HCoV-OC43
[21]
Chloroquine
[22]
Chloroquine
[3]
Chloroquine
Feline infectious
peritonitis virus
(FIPV)
SARS-CoV
MERS-CoV
HCoV-229E-GFP
(GFP-expressing
recombinant
HCoV-229E)
SARS-CoV-2
HRT-18 cells
Newborn C57BL/6 mice; chloroquine
administration transplacentally and
via maternal milk
Felis catus whole fetus-4 cells
Antiviral effect
EC50 = 8.8 ± 1.2 μM
EC50 = 4.4 ± 1.0 μM
Chloroquine: EC50 = 1–4 μM
Chloroquine monophosphate: EC50 = 4–6 μM
Chloroquine diphosphate: EC50 = 3–4 μM
Intraperitoneal or intranasal chloroquine administration,
beginning 4 h prior to virus exposure: 50 mg/kg but
not 10 mg/kg or 1 mg/kg reduced for the intranasal
route (but not the intraperitoneal route) viral lung
titres from mean ± S.D. of 5.4 ± 0.5 to 4.4 ± 1.2 in
log10 CCID50 /g at Day 3 (considered as not significant)
Chloroquine: EC50 = 6.5 ± 3.2 μM
Hydroxychloroquine: EC50 = 34 ± 5 μM
Chloroquine: EC50 > 0.8 μM
Hydroxychloroquine: EC50 = 28 ± 27 μM
Chloroquine at concentrations of 10 μM and 25 μM
inhibited..
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