Peer-Reviewed Report Examines Pre-Exposure Prophylaxis for COVID-19

Peer-Reviewed Report Examines Pre-Exposure Prophylaxis for COVID-19

Borrowing from successful malaria and HIV/AIDS prophylaxis, a new report suggests rethinking the use of a controversial Food and Drug Administration (FDA)-approved medication to avoid severe viral infection and death from COVID-19. The peer-reviewed report was published by the prestigious medical journal Infection and Drug Resistance. It is available here.
The report entitled “Flattening the Risk: Pre-Exposure Prophylaxis for COVID-19” was written by internist Raphael Stricker and nurse practitioner Melissa Fesler from Union Square Medical Associates in San Francisco, CA, and expands on a previous TrialSite News podcast. The authors have extensive experience treating patients with tick-borne diseases and recently published a proposal for early treatment of SARS-CoV-2, the viral agent of COVID-19, based on that experience.
The proposal for pre-exposure prophylaxis (PrEP) of COVID-19 focuses on hydroxychloroquine (HCQ). This controversial antimicrobial agent gained notoriety when it was considered for treatment of severe SARS-CoV-2 infection using high daily doses in combination with azithromycin. The regimen appeared to have antiviral efficacy based on reports from France and the United States, but concerns about cardiac toxicity and retinal damage have limited its use. The fact that HCQ treatment became politicized added to the controversy over its value for SARS-CoV-2 therapy.
In the latest report, the authors point out several attractive features of HCQ that were overlooked in the midst of the controversy: HCQ has an extremely long half-life of 40 days in the human body, which makes it an ideal candidate for prophylaxis of viral infection. It is approved by the FDA and has been used for malaria prophylaxis for decades in limited weekly dosing, which avoids the toxicity seen with high daily doses. It is also cheap and readily available if dosing is kept to a minimum. Other medications such as ivermectin have been suggested for disease prevention, but PrEP studies using these agents are lacking. Although feverish work on a protective COVID-19 vaccine continues, realistically a safe and effective vaccine product is nowhere in sight.
“We realized that HCQ could be safely used to avoid severe viral infection,” says Fesler. “It is the same principle that led to prevention of malaria and HIV/AIDS. We may not be able to avoid infection completely with this approach, but we hope to limit COVID-19 severity and transmission.”
The researchers pointed to groups at high risk for COVID-19, including healthcare providers and first responders, patients with hypertension, diabetes or obesity, and the elderly. Individuals who harbor Neanderthal genes also appear to be at higher risk for serious infection. Weekly PrEP with HCQ should benefit these groups and avoid severe disease. Six international cohort studies covering almost 400,000 people support this approach, and two randomized controlled trials in the United States found that 1,053 healthcare workers using HCQ PrEP had no hospitalizations, no deaths and no cardiac complications. Furthermore, once-weekly HCQ dosing appeared to work as well as twice-weekly or daily dosing. Unfortunately, the studies were terminated prematurely because of the controversy over HCQ.
“Although HCQ has been misused and demonized, it provides a sound approach to PrEP,” says Stricker. “We have an urgent need for a practical way to prevent serious viral infection, and with COVID-19 cases on the rise again and no end in sight we have everything to gain and nothing to lose with this strategy.”

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  1. Hydroxychloroquine, 200 mg twice per week, along with Daily zinc, vitamin d. Is probably more effective than typical vaccine.

    1. And everyone should be taking N-Acetyl-Cysteine 600 mg twice daily. As DeFlora recorded in 1997 from the landmark Italian study, it is about twice as effective as the average influenza vaccine at preventing/treating influenza H1N1 and has subsequently been shown to help RSV dramatically. It would seem to be the first repurposed “drug” to apply to coronaviruses but no registered trials are published.

      A JAMA viewpoint is that the amount of immunity is proportional to viral load, though they gave no evidence. The trick then would seem to get just enough virus to vaccinate yourself without getting sick. So, yes, when I’m exposed at the workplace to Covid-19, I wait 3 days and take a dose of ivermectin. Haven’t got sick, don’t know if I have antibodies.

      This is so old-fashioned. Like the days before “evidence-based Medicine” where you took your med school training and experience and made it up as you went along. But if the only “evidence” we are allowed to consider is that sponsored by Big Pharma or matching Phase 3 protocols, and you have to wait for official guidelines from those who would not profit by them, it is very reasonable to at least try the “kitchen-sink” approach. Pick any number of cheap and safe and possibly effective interventions and try them all.

  2. HCQ or Ivermectin. Has anyone conducted an in vitro experiment on HCQ such as the one done on Ivermectin ay Monash University?

    I applaud the PrEP approach. Much energy is consumed on critical care options so any science based effort to address PrEP or even early stage intervention would be helpful.

    Also, since this is focused on pre-exposure period, I would think that a double blind placebo group would not be add much to the picture if study participants are pseudo randomly chosen.

    My suspicion is that many clinicians are already dosing with this, Ivermectin, a few antibiotics and a few other OTC remedies. The people need the HOPE of a pre-vaccine reasonably effective solution…

    My recommendation:

    1) 2 groups – HCQ and Ivermection
    2) not another 6 – 12 month study that overlaps with vaccine introduction.
    3) Stay within standard dosing so as not to bring safety into question of both Ivermectin and HCQ.
    4) Make it as large as possible so that the statistical evidence would mimic the population as a whole
    5) Consider whether participants are more or less likely to follow CDC guidance on masking, social distancing etc.
    6) Require flu shots to minimize confusion over development of symptoms?

    1. Many HCQ studies have been done already, in vitro and in vivo. A few of them were even honest; many were built to fail for political/financial reasons. Find the ones that use the standard malaria dosage (400mg day 1, 200mg day 2-5) and zinc and some kind of antibiotic, for early to middle level infections, and read those results.

      Ivermectin seems to work in a similar fashion, but may help with more severe cases, where HCQ no longer works. And at this point, any of these “method studies” – protocol tests actually, not just looking at 1 isolated drug, ought to at least include hefty amounts of vitamin D, and intravenous vitamin C for hospitalized patients.

      And let go of this double blind placebo nonsense. Giving a sugar pill to sick people during a global pandemic, leaving them to get sicker or die, is psychotically unethical IMO.

      I don’t think we need many more studies on existing well tested individual drugs at this point. What we need is short term studies that work to find the most effective treatments. The treatment answer is going to be some “cocktail” of multiple approaches. Save the individual drug studies for the repurposed drugs and the naturopathic remedies.

      1. Drew, I whole heartedly agree on the unethical nature of the RCT studies during a pandemic. You put it very plainly, giving sick people a sugar pill during a pandemic and watch them die is unethical, and beyond the pale. The studies have been done. I for one do not have to wait for the studies to be done in the west. The studies completed on Ivermectin in the poor and third world are more than adequate. Ivermectin helps reduce the severity of Covid and saves lives. It is FDA approved and safe. Let’s get using this medication.

  3. By his own admission President Trump was taking hydroxychloroquine and zinc as a prophylaxis for COVID-19 and yet not only did he come down with the disease but he deteriorated quickly. I know this is only n-1 but it certainly demonstrates HCL isn’t a magic bullet against COVID-19.

    1. Do you know if he continued to take it, or if he stopped because of the insane media reaction? And how light a prophylaxis dose was he taking? And I don’t agree that he deteriorated quickly, as he was reportedly lightly sick, instantly went to the hospital, and was out and healthy 3 days later, having had the energy to do a couple of videos and a ride-around while there.

      The President is exposed to a huge number of people on a daily basis so his odds of exposure are much greater than mine. So no, not a perfect mythical “magic bullet”, but we have no idea how many thousand times he was near people who were infectious, and he got a mild case just once. Once. Sounds pretty magical to me. AFAIK, all the access checker people do is take your temperature. Anybody sick could just take a couple aspirin and pass that test.

  4. The doctors mentioned above are absolutely right and it is amazing to me that anyone who knows anything about HDQ and Ivermectin being used around the world should be screaming for the governments around the world to promote these already approved drugs be handed out freely with recommended dosage requirements. It is bound to help. If there is an occasional side effect it would likely be far outweighed by the covid case reductions.