Hydroxychloroquine / Plaquenil and the Covid-19 / Coronavirus


Senior Member
Chinese found an In Vitro activity of Plaquenil, and maybe in Vivo too but the live study is not yet published.

A Professor in France got interested in doing a trial in Marseille hospital, and was agreed a few days ago to do so Pr Raoult;

He is studying Plaquenil use in viral and intracellular bacterial infection for a long time, and his team showed efficiency with Doxycycline against T. Whipplei.

Extract of a french article:

"Un consensus d'experts recommande dans les articles scientifiques cités ci-dessus d'inclure, en Chine, le phosphate de chloroquine dans les recommandations de prise en charge des patients, à raison de 500 mg deux fois par jour pendant 10 jours. La chloroquine présente deux risques majeurs. Le premier, la cécité, n'apparaîtrait que lorsque le médicament est pris au long cours, sur plusieurs années (dans le cas du coronavirus, il s'agirait de le prendre pendant une dizaine de jours). "Toutefois, 500 mg deux fois par jour est certes une dose importante", admet Didier Raoult, spécialiste des maladies infectieuses à l'Assistance publique des hôpitaux de Marseille (APHP). L'autre effet indésirable est celui d'une intoxication aiguë bien documentée, susceptible de déclencher des problèmes cardiaques ou respiratoires. La dose recommandée par les chercheurs chinois approche cette zone de risque (20 mg/kg/jour à ne pas dépasser, soit 1200 mg pour une personne de 60 kg, 1500 mg pour 75 kg, selon le Vidal)."

Of chloroquine and COVID-19
Franck Touret Xavier de Lamballerie
Unité des Virus Emergents, UVE: Aix Marseille Univ, IRD 190, INSERM 1207, IHU Méditerranée Infection, 13005, Marseille, France
Received 29 February 2020, Revised 2 March 2020, Accepted 2 March 2020, Available online 5 March 2020.

https://doi.org/10.1016/j.antiviral.2020.104762Get rights and content


In vitro data suggest that chloroquine inhibits SARS Cov-2 replication.

In past research, chloroquine has shown in vitro activity against many different viruses, but no benefit in animal models.

Chloroquine has been proposed several times for the treatment of acute viral diseases in humans without success.

The outcomes of some current clinical trials of chloroquine in China have been announced, without access to the data.

Peer review of the results and an independent assessment of the potential benefit for patients are essential.

Recent publications have brought attention to the possible benefit of chloroquine, a broadly used antimalarial drug, in the treatment of patients infected by the novel emerged coronavirus (SARS-CoV-2). The scientific community should consider this information in light of previous experiments with chloroquine in the field of antiviral research.


Recent publications have brought attention to the possible benefit of chloroquine, a broadly used antimalarial drug, in the treatment of patients infected by the novel emerged coronavirus (SARS-CoV-2) (Colson et al., 2020; Gao et al., 2020).

The scientific community should consider this information in light of previous experiments with chloroquine in the field of antiviral research.

The sulfate and phosphate salts of chloroquine have both been commercialised as antimalarial drugs. Hydroxychloroquine has also been used as an antimalarial, but in addition is now broadly used in autoimmune diseases such as lupus and rheumatoid arthritis. Of note, chloroquine and hydroxychloroquine are considered to be safe and side-effects are generally mild and transitory. However, the margin between the therapeutic and toxic dose is narrow and chloroquine poisoning has been associated with cardiovascular disorders that can be life-threatening (Frisk-Holmberg et al., 1983). Chloroquine and hydroxychloroquine use should therefore be subject to strict rules, and self-treatment is not recommended.

The in vitro antiviral activity of chloroquine has been identified since the late 1960's (Inglot, 1969; Miller and Lenard, 1981; Shimizu et al., 1972) and the growth of many different viruses can be inhibited in cell culture by both chloroquine and hydroxychloroquine, including the SARS coronavirus (Keyaerts et al., 2004). Some evidence for activity in mice has been found for a variety of viruses, including human coronavirus OC43 (Keyaerts et al., 2009), enterovirus EV-A71 (Tan et al., 2018), Zika virus (Li et al., 2017) and influenza A H5N1 (Yan et al., 2013). However, chloroquine did not prevent influenza infection in a randomized, double-blind, placebo-controlled clinical trial (Paton et al., 2011), and had no effect on dengue-infecteds patient in a randomized controlled trial in Vietnam (Tricou et al., 2010). Chloroquine was also active ex vivo but not in vivo in the case of ebolavirus in mice (Dowall et al., 2015; Falzarano et al., 2015), Nipah (Pallister et al., 2009) and influenza virus (Vigerust and McCullers, 2007) in ferrets.

The case of chikungunya virus (CHIKV) is of specific interest: chloroquine showed promising antiviral activity in vitro (Coombs et al., 1981; Delogu and de Lamballerie, 2011), but was shown to enhance alphavirus replication in various animal models (Maheshwari et al., 1991; Roques et al., 2018; Seth et al., 1999), most probably because of the immune modulation and anti-inflammatory properties of chloroquine in vivo (Connolly et al., 1988; Katz and Russell, 2011; Savarino et al., 2003). In a nonhuman primate model of CHIKV infection, chloroquine treatment was shown to exacerbate acute fever and delay the cellular immune response, leading to an incomplete viral clearance (Roques et al., 2018). A clinical trial conducted during the chikungunya outbreak in 2006 in Réunion Island showed that oral chloroquine treatment did not improve the course of the acute disease (De Lamballerie et al., 2008) and that chronic arthralgia on day 300 post-illness was more frequent in treated patients than in the control group (Roques et al., 2018). Altogether, the assessment of previous trials indicates that, to date, no acute virus infection has been successfully treated by chloroquine in humans.

Chloroquine has also been tested in chronic viral diseases. Its use in the treatment of HIV-infected patients has been considered inconclusive (Chauhan and Tikoo, 2015) and the drug has not been included in the panel recommended for HIV treatment.

The only modest effect of chloroquine in the therapy of human virus infection was found for chronic hepatitis C: an increase of the early virological response to pegylated interferon plus ribavirin (Helal et al., 2016) and, in a small sample size pilot trial in non-responder HCV patients, a transient viral load reduction (Peymani et al., 2016) were observed. This was not enough to include chloroquine in the standardised therapeutic protocols for hepatitis C patients.

Recently, Wang and colleagues (Wang et al., 2020) evaluated in vitro five FDA-approved drugs and two broad spectrum antivirals against a clinical isolate of SARS-CoV-2. One of their conclusions was that "chloroquine (is) highly effective in the control of 2019-nCoV infection in vitro" and that its "safety track record suggests that it should be assessed in human patients suffering from the novel coronavirus disease".

At least 16 different trials for SARS-CoV-2 already registered in the Chinese Clinical Trial Registry (ChiCTR2000029939, ChiCTR2000029935, ChiCTR2000029899, ChiCTR2000029898, ChiCTR2000029868, ChiCTR2000029837, ChiCTR2000029826, ChiCTR2000029803, ChiCTR2000029762, ChiCTR2000029761, ChiCTR2000029760, ChiCTR2000029741, ChiCTR2000029740, ChiCTR2000029609, ChiCTR2000029559, ChiCTR2000029542) propose to use chloroquine or hydroxychloroquine in the treatment of COVID-19 ("Chinese Clinical Trial Register" (ChiCTR)).

In a recent publication (Gao et al., 2020), Gao and colleagues indicate that, "according to the news briefing", "results from more than 100 patients have demonstrated that chloroquine phosphate is superior to the control treatment in inhibiting the exacerbation of pneumonia, improving lung imaging findings, promoting a virus negative conversion, and shortening the disease course".

This would represent the first successful use of chloroquine in humans for the treatment of an acute viral disease, and is undoubtedly excellent news, since this drug is cheap and widely available. However, it should be considered carefully before drawing definitive conclusions, since no data has been provided yet to support this announcement.

Results were produced in ten different hospitals and possibly from a number of different clinical protocols among those listed above, which include various designs for control groups (none, different antivirals, placebo, etc.) and various outcome primary indicators.

The final interpretation is therefore technically demanding, and in the absence of published data, it is difficult to reach any firm conclusion. It will be of the utmost importance to know if the observed efficacy is associated specifically with chloroquine phosphate, or if this includes other salts (e.g., sulfate) of chloroquine, and hydroxychloroquine.

It is also necessary to determine if the benefit of chloroquine therapy depends on the age class, the clinical presentation or the stage of the disease.

In conclusion, the option of using chloroquine in the treatment of SARS-CoV-2 should be examined with attention in light of the recent promising announcements, but also of the potential detrimental effect of the drug observed in previous attempts to treat acute viral diseases.

We urge Chinese scientists to report the interim trial results currently running in China as soon as they are available. This should be preferentially done in a peer-reviewed publication with detailed information to allow the international scientific community to analyse the results, to confirm in prospective trials the efficacy of the proposed treatment and to guide future clinical practice.

Maladie de Whipple et infections à Tropheryma whipplei
Whipple's disease and Tropheryma whipplei infections

J.-C. Lagier a, b,

a URMITE, UM63, CNRS 7278, IRD 198, Inserm 1095, faculté de médecine, Aix-Marseille université, 27, boulevard Jean-Moulin, 13385 Marseille cedex 5, France
b IHU Méditerranée infection, pôle Infectieux, service de maladies infectieuses et tropicales, hôpital Nord, AP–HM, chemin des Bourrelys, 13015 Marseille, France

⁎URMITE, UM63, CNRS 7278, IRD 198, Inserm 1095, faculté de médecine, Aix-Marseille université, 27, boulevard Jean-Moulin, 13005, Marseille, France.


Whipple's disease, caused by Tropheryma whipplei , involves mainly more than 50 years old Caucasian male, suffering of arthralgia, weight loss and diarrhea.

Immunosuppressive treatment prescribed for an erroneous diagnosis of inflammatory rheumatism can cause a worsening of clinical manifestations while antibiotics prescribed for concomitant infection improves the clinical status.

Positive T. whipplei PCR performed on saliva and stool samples are a screening suggestive of Whipple's disease. The diagnosis must be confirmed by positive periodic acid Schiff staining or immunohistochemistry performed on small-bowel biopsies.

Localized chronic infections are defined by the absence of histological duodenal involvement.

Endocarditis mainly occurs in 60-year-old men with arthralgia, cardiac insufficiency or embolic events, frequently without fever.

Encephalitis causes diverse clinical involvement mainly with cognitive and psychiatric involvement, dementia, ataxia and weight gain.

Uveitis and arthritis are typically chronic, and are frequently resistant to immunosuppressive treatment. PCR performed on various tissues and fluids are the key of the diagnosis, but culture is more sensitive in neurological involvement.

The treatment with doxycycline (200mg/day) and hydroxychloroquine (600mg/day) for a length of 12 months followed by a lifetime treatment by doxycycline (200mg/day) should be recommended in classic Whipple's disease.

In localized infections, a treatment with doxycycline (200mg/day) and hydroxychloroquine (600mg/day) is recommended for 12 to 18 months followed by a lifetime follow-up.

The full text of this article is available in PDF format.

Keywords : Whipple's disease, Tropheryma whipplei , Endocarditis, Encephalitis, Arthritis


Senior Member
In Vitro Antiviral Activity and Projection of Optimized Dosing Design of Hydroxychloroquine for the Treatment of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)
25 February 2020
09 March 2020

  • Cite
    Xueting Yao, Fei Ye, Miao Zhang, Cheng Cui, Baoying Huang, Peihua Niu, Xu Liu, Li Zhao, Erdan Dong, Chunli Song, Siyan Zhan, Roujian Lu, Haiyan Li, Wenjie Tan, Dongyang Liu,

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) first broke out in Wuhan (China) and subsequently spread worldwide. Chloroquine has been sporadically used in treating SARS-CoV-2 infection.

Hydroxychloroquine shares the same mechanism of action as chloroquine, but its more tolerable safety profile makes it the preferred drug to treat malaria and autoimmune conditions. We propose that the immunomodulatory effect of hydroxychloroquine also may be useful in controlling the cytokine storm that occurs late-phase in critically ill SARS-CoV-2 infected patients. Currently, there is no evidence to support the use of hydroxychloroquine in SARS-CoV-2 infection.

The pharmacological activity of chloroquine and hydroxychloroquine was tested using SARS-CoV-2 infected Vero cells. Physiologically-based pharmacokinetic models (PBPK) were implemented for both drugs separately by integrating their in vitro data. Using the PBPK models, hydroxychloroquine concentrations in lung fluid were simulated under 5 different dosing regimens to explore the most effective regimen whilst considering the drug’s safety profile.

Hydroxychloroquine (EC50=0.72 μM) was found to be more potent than chloroquine (EC50=5.47 μM) in vitro. Based on PBPK models results, a loading dose of 400 mg twice daily of hydroxychloroquine sulfate given orally, followed by a maintenance dose of 200 mg given twice daily for 4 days is recommended for SARS-CoV-2 infection, as it reached three times the potency of chloroquine phosphate when given 500 mg twice daily 5 days in advance.

Hydroxychloroquine was found to be more potent than chloroquine to inhibit SARS-CoV-2 in vitro.


Any opinion on Isoprinosine? It was discussed on this forum few years ago regarding other viral infections so I thought I'd bring it up. I believe it's more of an immunomodulator and was wondering how I can buy it here in the U.S.


Senior Member
It’s a high dose of hydroxychloroquine. Dose used in lupus usually 200mg twice a day.. maintenance sometimes 200mg once a day. Very interesting, thanks.


Moose Enthusiast
That's fascinating. It's good to see that doctors are figuring out that there are some existing drugs are found to help this illness, so hopefully they can treat people more quickly and effectively so they don't get as sick for as long. And to my knowledge hydroxychloroquine is cheap and pretty safe as drugs go.

At the beginning of my illness, when my doctor thought I had lupus, I think I was on 200mg a day.


Senior Member
Any opinion on Isoprinosine? It was discussed on this forum few years ago regarding other viral infections so I thought I'd bring it up. I believe it's more of an immunomodulator and was wondering how I can buy it here in the U.S.
Note that we don't know yet if hydroxychloroquine activity against SRAS-COV-2 is from it's antiviral or it's immunomodulatory/immunosuppressive effect.

It’s a high dose of hydroxychloroquine. Dose used in lupus usually 200mg twice a day.. maintenance sometimes 200mg once a day. Very interesting, thanks.

yes it's a high dose that is proposed
-hydroxychloroquine 2 x 400 mg the first day then 2 x 200 mg from day 2 to day 5.
-chloroquine 2 x 500 mg per day for 10 days

But on the other hand Pr Raoult already knows hydroxychloroquine toxicity on the long run while using it at higher dosage against T. Whipplei, so the team has some experience on the management (heart and eyes must be especially looked after)

"The treatment with doxycycline (200mg/day) and hydroxychloroquine (600mg/day) for a length of 12 months followed by a lifetime treatment by doxycycline (200mg/day) should be recommended in classic Whipple's disease. "


Senior Member
Yikes. If I had to choose between the deafening tinnitus I got when on Plaquenil and coronavirus, it might be a difficult choice :xeyes:. Plaquenil is actually a pretty safe medication: the often-cited rentinopathy is primarily a risk in patients taking it long term (>5 years) for rheumatological diseases. The tinnitus subsided after I stopped taking Plaquenil, although it took a long time because it has a 22 day half-life!


Does isopropyl alcohol actually help with the coronavirus vs. a stringent like witch hazel?


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Does isopropyl alcohol actually help with the coronavirus vs. a stringent like witch hazel?

Yes WHO organisation advice is 60% alcohol for hand sanitisers. There’s no advice on Witch Hazel. It might not have been tested against coronavirus so best not to rely on it.


Senior Member
Pr Raoult team in Marseille/ France just published a short trial with Hydroxychloroquine and Azithromycin.
I have pulmonary issues and my husband had leukemia, so I am considering this treatment option, although it's not clear if it gives any survival rate improvement...

Hydroxychloroquine and azithromycin as a treatment of COVID-19: results of an open label
non-randomized clinical trial


Despite its small sample size our survey shows that hydroxychloroquine treatment is
significantly associated with viral load reduction/disappearance in COVID-19 patients and its
effect is reinforced by azithromycin."

Hospitalized patients with confirmed COVID-19 were included in this study if they fulfilled
two primary criteria: i) age >12 years; ii) PCR documented SARS-CoV-2 carriage in
nasopharyngeal sample at admission whatever their clinical status.
Patients were excluded if they had a known allergy to hydroxychloroquine or chloroquine or
had another known contraindication to treatment with the study drug, including retinopathy,
G6PD deficiency and QT prolongation."

"All patients in Marseille center were proposed oral hydroxychloroquine sulfate 200 mg, three times per day during ten days"

"Among hydroxychloroquine-treated
patients six patients received azithromycin (500mg on day1 followed by 250mg per day, the
next four days)"

"We show here that hydroxychloroquine is efficient in clearing viral nasopharyngeal carriage
of SARS-CoV-2 in COVID-19 patients in only three to six days, in most patients. A
significant difference was observed between hydroxychloroquine-treated patients and controls
starting even on day3 post-inclusion."


  • Hydroxychloroquine_final_DOI_IJAA (1).pdf
    312.8 KB · Views: 15


I saw Trump saying is approved? Is this the same as sumarin (or something like that) that they wanted to try for cfs?? ALl I remember it was a malaria drug we couldn't get our hands on.


Senior Member
From an other forum:

Posted Yesterday, 10:13 PM
Trump is talking about hydroxychloroquine and it effectiveness and that the
FDA will give clearance to make the drug available for immediate use against this virus.​
But here is a revealing backstory on these 'studies' and why this story has some hallmarks of a social media scheme. It's a story when Elon tweets it.

(3 hr old story as I post this)


Senior Member
Its disappearing fast and will soon be unavailable..it appears.


People with Lupus and arthritis who need it, are now having trouble getting it.

It appears natural selection is strongly at work. Those who delay, may just be Up a Creek with no paddle.
Yup. I take it regularly for autoimmunity issues. I'm going to stop taking it to save it for me & my family if we get coronavirus. Luckily, I just refilled it for 3 months. So I have 2.25 months of supply left.

I'm worried lots of other drugs are going to run out. Azithromyzin, like in the paper used for coronavirus, and perhaps other important drugs like antibiotics.


Senior Member
Dr. Jose Montoya tweeting about treatment of CoVID-19 with hydroxychloroquine and azithromycin.

Looks like he is still working in the S.F. Bay Area at the Dr, Jack S, Remington Specialty Diagnostics Laboratory. So sad that he is no longer at Stanford doing research re ME/CFS. .
The diagnosis of toxoplasmosis may be established by serological tests, polymerase chain reaction (PCR), histological demonstration of the parasite and/or its antigens (i.e. immunoperoxidase stain), or isolation of the organism. The Dr. Jack S. Remington Laboratory for Specialty Diagnostics offers confirmatory serological and PCR testing and methods for isolation of the organism. In addition, our medical consultants (Jose G. Montoya, M.D. and Jack S. Remington, M.D.) are available for interpretation of test results and advice on management of patients.
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Senior Member
Donald Trump explodes in anger after being asked if he is giving false hope to 'scared' Americans by

buying malaria drug as he called 'game-changer' coronavirus cure - despite Tony Fauci saying there is NO proof it works or is even SAFE

President Donald Trump told reporters the nation has ordered 'millions' of units of the drug 'cloroquine' that he said he has a 'feeling' will be effective against the coronavirus. 'We ordered them. We have millions of units ordered,' Trump said, name checking the German manufacturer Bayer, which he called a 'great company.' 'Millions of units are ordered and we’re going to see what happens,' Trump said. Trump and health officials referenced the drug yesterday as among those having promising potential to alleviate those suffering from the coronavirus – although Trump was immediately contradicted on claims that it was ready for use. When asked by an NBC News reporter whether he was giving Americans false hope and putting on a 'positive spin' over when Dr.Fauci has said there is no magic drug, Trump lost his cool. 'I would say that you're a terrible reporter, that's what I'd say,' Trump erupted. 'I think it's a very nasty question.' He scolded the reporter: 'The American people are looking for answers and they're looking for hope. And you're doing sensationalism,' Trump said. He wagged his finger for emphasis and said: 'That's really bad reporting.' 'Let's see if it works. I happen to feel good about it. Who knows? I have been right a lot. Let's see what happens,' Trump said.

Elon Musk and Trump are touting a 1940s malaria pill as a potential coronavirus treatment. But supplies are already running short as prescriptions spike.

Chloroquine and the safer, more widely used variant called hydroxychloroquine have rapidly gone into shortage as demand has spiked, thanks to early reports that the pills may work to treat COVID-19, the disease caused by the novel coronavirus. . . .

Chloroquine, which is made by one manufacturer in the US and was approved in the country in 1949, has been in shortage since March 9, according to the American Society of Health-System Pharmacists. Hydroxychloroquine, sold under the brand name Plaquenil, went into shortage on Thursday, according to the pharmacy group, with four of its eight suppliers affected.

And while it remains to be seen if these pills will work for COVID-19, they have been approved by regulators as a safe and effective medication for malaria, lupus, and rheumatoid arthritis. . . .

Drug manufacturers are now working to meet the demand. Amneal is working to increase production, according to a person familiar with the company's plans. Mylan said it would restart hydroxychloroquine manufacturing at a West Virginia plant. The Indian healthcare company Zydus Cadila said it's increasing production as well.

Teva Pharmaceutical Industries said it plans to donate more than 10 million tablets of hydroxychloroquine to US hospitals within a month.
"Immediately upon learning of the potential benefit of hyroxychloroquine, Teva began to assess supply and to urgently acquire additional ingredients to make more product while arranging for all of what we had to be distributed immediately," Brendan O'Grady, an executive vice president at the drugmaker, said in a statement.

Sandoz, the generics arm of the pharmaceutical company Novartis, said it had a good supply of hydroxychloroquine in the US. On Friday, Novartis committed to donate up to 130 million doses of the drug to support the global response. . . .

Bayer AG said on Thursday it has donated 3 million tablets of the malaria drug Resochin to the U.S. government for potential use to treat COVID-19.

https://apnews.com/Business Wire/8075f513189d40c4bd2dd46b528202e0
TEL AVIV, Israel & PARSIPPANY, N.J.--(BUSINESS WIRE)--Mar 19, 2020--
Teva Pharmaceutical Industries Ltd. (NYSE and TASE: TEVA) announced today the immediate donation of more than 6 million doses of hydroxychloroquine sulfate tablets through wholesalers to hospitals across the U.S. to meet the urgent demand for the medicine as an investigational target to treat COVID-19.

Novartis makes the malaria drug, which is also used to treat lupus and rheumatoid arthritis, at its Sandoz unit in the United States. It plans to donate 130 million doses of the drug and is in talks with U.S. Food and Drug Administration regulators over expanding its use for coronavirus.
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