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Hydroxychloroquine doesn't prevent people from catching COVID-19, study finds

A man taking a pill from a blister pack.
(Image: © Shutterstock)

Taking the antimalarial drug hydroxychloroquine did not prevent people from coming down with COVID-19 after being exposed to the disease, according to a new study.

The study, published Wednesday (June 3) in the New England Journal of Medicine, is the first of its kind to examine hydroxychloroquine as a way to prevent COVID-19, rather than to treat it in people who are already sick with the disease, according to The Washington Post

Hydroxychloroquine has gained attention in recent months after President Donald Trump called it a potential "game changer" and revealed he had taken it for several days as a way to protect against COVID-19 infection, despite a lack of evidence that it works for this purpose, the Post reported.

The study findings are "not surprising given that there has not been efficacy established for this drug in any meaningful way" for COVID-19, Dr. Eric Topol, director of the Scripps Research Translational Institute in San Diego, who was not involved in the study, told the Post.

The new study, from researchers at the University of Minnesota, involved 821 people who were exposed to a person with COVID-19, either because they were a healthcare worker or because someone in their household tested positive for the disease. The participants were randomly assigned to receive hydroxychloroquine or a placebo within four days of their exposure. The study was "double blind," meaning that neither the doctors nor the participants knew which group they were assigned to.

After two weeks, about 12% of participants in the hydroxychloroquine group developed symptoms of COVID-19 compared with 14% of participants in the placebo group, a difference that was too small to be meaningful or "statistically significant."

The study also found that about 40% of people in the hydroxychloroquine group experienced side effects, most commonly nausea, upset stomach and diarrhea, compared with 16% in the placebo group. No serious side effects, such as heart complications, were reported. (Other studies have raised safety issues with this class of drugs. For example, a Brazilian study testing the related drug chloroquine for COVID-19 had to be stopped early after some patients taking high doses of the drug developed dangerous heart rhythm problems, Live Science previously reported.)

One limitation of the new study is that, when it began in mid-March, COVID-19 testing in the U.S. was not widely accessible, and so the study was not able to broadly check for asymptomatic cases of COVID-19. Instead, most participants were diagnosed based on symptoms alone, with only about 15% of cases being confirmed with a lab test. Still, the authors note that because the study was randomized, other illnesses that could not be ruled out (such as influenza), should have been equally distributed between the two groups.

In addition, study participants tended to be relatively young (the average age was 40 years old), and it's unclear whether hydroxychloroquine would have more of a benefit for high-risk groups such as older adults, the authors said.

Originally published on Live Science.  

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  • fireantap
    Interesting but doesn't seem to agree with
    https://publichealth.yale.edu/news-article/25085/
    Reply
  • Dr deswift
    To fight malaria you take this drug for at least 7 days before you go to a malaria zone. Taking the drug after you have caught malaria is useless as it would be to take the drug after you have caught Covid 19.
    Reply
  • CTYankee
    https://www.thelancet.com/lancet/article/s0140673620313246
    Reply
  • OldEnuf2KnowYetDoItAnyway
    Hydroxychloroquine works to open ionic passageways for zinc to enter into cells. Since the virus cannot add energy to it's replication process, when the enzymes produced under the command of the viral RNA is assembled into duplicate virus, the process must follow an energy cascade. Zinc appears to interfere with that cascade mechanism and thus reduces replication efficiency. This is not a preventative. It is a way to reduce infection efficiency. Although the article in question would be correct in that taking hydroxychloroquine would not confer immunity, taking hydroxychloroquine with zinc should decrease viral efficiency.

    It worked as a treatment in South Korea. Why wouldn't it work in the US unless political bias against Trumps' endorsement was blinding researchers?
    Reply
  • ads
    admin said:
    Taking the antimalarial drug hydroxychloroquine did not prevent people from coming down with COVID-19 after being exposed to the disease.

    Hydroxychloroquine doesn't prevent people from catching COVID-19, study finds : Read more
    This paper has been poorly done. The patients were given HCQ after 4 days of exposure. If you put a condom on four days after, guess what? You're having a kid. HCQ is meant to be given before exposure. Also they never tested the subjects for cov before or after patients are presumed cases from self reporting. Let me say again the patients we're not physically examined and reported to a website themselves. The paper has come under major scrutiny and the authors have removed it from the lancet. It should have never got into the Lancet, big black eye for them publishing junk science. In India they are having success with it = “Biologically, it appears plausible that HCQ prophylaxis, before onset of infection, may inhibit the virus from gaining a foothold,” stated ‘Healthcare workers & SARS-CoV-2 infection in India: A case-control investigation in the time of COVID-19’, a study published recently in the Indian Journal of Medical Research. https://indianexpress.com/article/india/preventive-use-of-hcq-in-frontline-healthcare-workers-icmr-study-6442948/
    Reply
  • GWK
    I'm confused at some of the thoughts on HCQ. As best I recall no one claimed it prevented the disease, or cured it. At best the claims were that it, and I quote "showed promise" in treating Covid by decreasing the time to recovery, and increasing the rates of survival. The best thing is that it is readily available, cheap, off patent and most studies show that it does in fact reduce recovery time and increase recovery rates. Even if it is, as reports indicate, only 17% effective in decreasing duration and increased recoveries, I'll take it.
    Yet politics have gotten deeply involved in science. HCQ for decades has been shown to be safe. At this point, it's as safe as acetaminophen. If there is a possible benefit, why not.
    Reply
  • chrisko
    admin said:
    Taking the antimalarial drug hydroxychloroquine did not prevent people from coming down with COVID-19 after being exposed to the disease.

    Hydroxychloroquine doesn't prevent people from catching COVID-19, study finds : Read more
    I've never seen, heard or read anything that suggested it did prevent people from getting infected! So far, there is NOTHING that has shown that it can prevent people from becoming infected . . . other than 100% total isolation. N95 masks don't 100% prevent infection, social distancing doesn't 100% protect against infection. No vaccines have been shown to 100% prevent infection (of course, they're still being developed).

    In the USA (at least), this is largely a political thing in the media. If President Trump says anything, our media will run headlines that it is wrong, dumb, a lie, etc. . . I remember when he said based on what he'd seen and learned so far, his gut is that the death rate will likely be much more like 0.5% to 1.5%. The media lambasted him and quoted all sorts of scientists (including from the WHO) who suggested the death rate from Covid-10 would be in the 3.5% to 6+% range. And the media carried on with these claims for over a month. Of course, now that it is well established and recognized that even the 1.5% death rate (which was the highest end of Trump's estimate) is way too high versus reality! In all likelihood, the actual death rate will likely end up being very close to the 0.5% level, or even more likely, lower than that.

    The scientists have gotten so much wrong with regards to Covid-19, actually, looking back at the February and March scientific statements and projections - scientists have gotten far more wrong than they have gotten right. But this is the general nature and history of science. I think we all seem to forget that science is wrong about 90% of the time . . . it is historical practice that the scientific community only finally gets it right (sometimes) after a lot of getting it wrong, learning from their many mistakes, bad theories and hypothesis and errors. This is not suggesting science should be ignored, but the reality is that science should often be taken as a grain of salt - in particular when it comes to NEW issues - which we know they have a tendency to get grossly wrong at the early stages of study and hypothesis. We also know and see, that much like society as a whole, the scientific community is very easily influenced by political beliefs and/or pressure - for better and for worse!
    Reply
  • Karl Moerder
    I think it's important to keep in mind that you don't test a drug; you test a protocol. That is, you test an entire procedure, a set of drugs given in specific doses at a ceretain stage in the disease on a selected group of patients and you monitor for specific outcomes.
    Reply
  • Crownlife
    Please refer to the article from Oak Ridge lab where IBM's SUMMIT supercomputer analyzed the molecular structure of thousands of molecules for their suitability for blocking the SARS-CoV-2 viral spike protein from engaging an ACE2 receptor on a human host cell. Hydroxychloroquine shows moderate potential, with a score of -5.6 and a ranking of 1123, but there are a number of natural flavonoids that are much higher ranked, including myricetin, quercetin, and luteolin, So I think hydroxychloroquine is a bit overrated due to Trump's promotion due to the fact that there happened to be a stockpile. But flavonoids are prevalent in colorful vegetables and available as supplements. There is even a propolis nasal spray that might be used as an inhaler or nebulizer fluid to get the flavonoid to the epithelial cells rapidly. It is also key, in any of these effectiveness studies, to accompany the medication with a zinc supplement. See for yourself: https://chemrxiv.org/articles/Repurposing_Therapeutics_for_the_Wuhan_Coronavirus_nCov-2019_Supercomputer-Based_Docking_to_the_Viral_S_Protein_and_Human_ACE2_Interface/11871402/4
    Reply
  • paperpushermj
    admin said:
    Taking the antimalarial drug hydroxychloroquine did not prevent people from coming down with COVID-19 after being exposed to the disease.

    Hydroxychloroquine doesn't prevent people from catching COVID-19, study finds : Read more
    So what was the dosage given...was it low , medium or the high dosage recommended
    Reply