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其实郭文贵说这些药或多或少都被证实有效的，不过我想他的目的是并不是为了人类健康吧
McGill关于伊维菌素的文章。加拿大卫生部警告不要使用抗寄生虫药伊维菌素治疗 COVID-19 （题目对应最后更新的文章）
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这都不是事儿
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再谈谈伊维菌素
2021-09-21 09:13:41Fanreninus
冬雪倘雅淡，不走也不嫌，春風若溫暖，遲到也喜歡。
再谈谈伊维菌素
在前一篇文(伊维菌素和新冠)里，我提到了伊维菌素为何会被一些人推崇，最初的原因是有人发现它和羟基氯喹一样，在体外有抗病毒作用。
对于药物发现和开发来讲，这只是第一步，在体外有抗病毒作用的化合物估计有成百上千，但并不是所有的都能用来作为抗病毒药物的。
要成为抗病毒药，必须经过很多实验来证明它在体内也安全有效，其中最关键的就是在病人身上进行测试的三期临床双盲对照试验。
伊维菌素不仅没有这样的资料，甚至连进行三期临床测试的条件都达不到。原因就是用现有的剂型和量，在体内根本就达不到期望浓度。
要想知道是否达到期望浓度，要有两个参数。
第一个就是人体内的浓度，由于血液比较容易采样，通常以血浆里的浓度来代表人体内的浓度。
第二个在什么浓度下，药物能够发挥其活性或者效力（potency）。 譬如说药物抑制其靶物或相关细胞活动的50%（IC50）或者90%（IC90）的浓度是多少。
血浆浓度如果高于IC90的话，药物就有可能发生效果，就达到了期望浓度。如果达不到的话，就很难产生作用。
那么使用现有剂型的ivermectin后体内能否达到期望浓度呢？
下面是服用各种剂型和剂量后在血液中达到的最高浓度，其中最高的是每毫升80纳克。把这个用分子量（875）一除即可换算成每升多少个摩尔的摩尔浓度，结果是0.09微摩尔。
这个浓度远远低于该药抑制病毒的IC90或者（~6微摩尔）IC50（2.8微摩尔），血浆最高浓度比IC90低30倍。这说明服用后，该药根本达不到抑制病毒所需的浓度。
下面这个链接里的一文也得出同样的结论。
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文中说：空腹服用批准剂量的伊维菌素后能达到的最大血浆浓度 (Cmax)比 50%抑制的浓度 (IC50; 2 µM) 低35倍，即使多给十倍的药，血液和肺部的药物也不可能达到期望的浓度。
如果是临床一期得到这样的结论的话，就不会对被测试的药继续进行第二期（小规模的安全性和效果观察）和第三期（大规模的效果和安全性观察）了，不然不仅浪费人力物力财力，还有违医学伦理。
所以说用伊维菌素治疗或者预防新冠是没有足够科学证据的，不仅没有临床试验得到的科学证据，就连理论上也经不起推敲。为了自己和他人的身体健康，不要一味媚俗。
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ahhhh 发表评论于 2021-09-21 12:51:07
随手查一篇文章：https://pubmed.ncbi.nlm.nih.gov/34265236/。 人家是这样结论得：“ it had shown only marginal benefit in successful discharge from the hospital with no other observed benefits. ”
即便是如此保守的效用，也不值得左媒如此的攻击，毕竟它的效用是正面的。相比之下，疫苗各种吹嘘的效用一级一级失守，到如今要靠其他人都打疫苗来保护（白等说的），而媒体至今如神般膜拜。
这就是典型的夺制高点，争话语权的伎俩。
Fanreninus 发表评论于 2021-09-21 12:13:06
回复 'cowwoman' 的评论 : 不管什么时候吃，浓度达不到也没有用。
cowwoman 发表评论于 2021-09-21 11:45:19
仔细读这篇文章。第一，文章说在两个实验里IVM dose X10 proofed dose 都没副作用，两个实验证明安全。第二，对付Covid 有没有作用这个文章没做实验，做了一个数学模型，仿真一个关于肺的参数，说量不够大到降低那个肺的参数。这个模型过于简单。Covid 19感染后8天病毒就消失在身体里，留下的是一堆病毒尸体。后来发生的肺炎和重症都是免疫系统过分攻击这些病毒尸体。并不是病毒继续繁殖腐败器官。所有医生开IVM强调一定要提前吃，马上吃，因为IVM有抑制病毒繁殖和抑制免疫系统发炎的特性。总体作用是防止Covid 发展到8天的状况。到8天后等晚了的时候再用IVM降低肺的那个参数已经不是IVM可以处理的了。医生说虽然也有些用，但关键是阳性后在8天内抑制病毒繁殖和发炎，而不是后期等繁殖完了发炎严重后去消炎。这个数学模型和仿真没考虑这些药理的病理的过程。可以参考说发炎后批准的量不够能给肺消炎。但治病在预防，和早期抑制，不是后来消炎。
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Health Canada warns against using anti-parasitic drug ivermectin to treat COVID-19
Published Tuesday, August 31, 2021 9:34PM EDTLast Updated Tuesday, August 31, 2021 9:40PM EDTPeople urged to stop misusing horse deworming drug
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A Manitoba farm supply store is concerned about people misusing a drug meant to deworm horses. CTV's Josh Crabb reports.
With demand high, doctors warn against Ivermectin
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Sales are up in Alberta for a livestock drug called Ivermectin that some people believe can treat COVID-19. Tyson Fedor reports.
Expert on the use of ivermectin to treat COVID-19
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Dr. Michael Chatenay is urging people not to use the ivermectin livestock dewormer to help treat COVID-19.
TORONTO -- In light of reports of people using ivermectin, an anti-parasitic drug for livestock, to prevent or treat COVID-19, Health Canada issued an alert Tuesday night telling Canadians not to consume animal health products at any time due to the serious dangers they pose to humans.
The agency has advised not to use either the human or veterinary versions of the drug to treat COVID-19, as there's no evidence that it is safe or effective for such purposes.
The human version of ivermectin is authorized for sale in Canada only for the treatment of parasitic worm infections in people. The veterinary ivermectin is used for treating parasites in animals and contains higher concentrations of the drug.
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- 'You are not a cow': FDA begs Americans to stop taking drug meant for livestock as COVID-19 remedy
- 'Miracle' drug ivermectin unproven against COVID, scientists warn
If you have purchased ivermectin as a COVID-19 treatment, Health Canada advises discarding it. If you have consumed the drug and have health concerns, you are also advised to consult a health-care professional and report any side-effects.
The U.S. Food and Drug Association pleaded with Americans on Aug. 21 not to take ivermectin as a treatment for COVID-19 in a tweet, saying: "You are not a horse. You are not a cow."
Scientists at least as far back as January have warned against its use.
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Fringe Doctors’ Groups Promote Ivermectin for COVID despite a Lack of Evidence
The organizations touting unproved protocols for the antiparasitic drug may be harming vaccination efforts- By Christina Szalinski on September 29, 2021
Credit: Alamy
Ivermectin has helped treat hundreds of millions of people and billions of pets and farm animals for parasitic diseases. Its discovery even garnered a Nobel Prize in Physiology or Medicine in 2015. But now several groups of doctors are encouraging and enabling people to take the drug off-label to treat or prevent COVID—despite a lack of solid evidence that it works against the disease and the fact that high doses can be harmful. In doing so, some experts believe these groups are undermining vaccination efforts.
Derived from a compound discovered in a soil microbe in Japan, ivermectin has been called a “miracle drug” and “the penicillin of COVID” by Pierre Kory, a critical care physician in Madison, Wis. Kory is president of the Front Line COVID-19 Critical Care Alliance (FLCCC), a group of physicians and scientists who champion ivermectin, along with other drugs and vitamins with dubious efficacy against COVID. The organization, along with two others called the British Ivermectin Recommendation Development (BIRD) Group and America’s Frontline Doctors (AFLDS), have drawn criticism from many other physicians and scientists. Yet treatment protocols, links and videos from these groups are sweeping through social media, promoted by vaccine skeptics.
The notion that ivermectin is a miracle medicine gives people who reject vaccines a false sense of security, says Daniel Griffin, a physician and infectious disease researcher at Columbia University and Chief of the Division of Infectious Disease at the company ProHEALTH. A recent poll by the Economist and YouGov indicated that a total of about 56 percent of people who believe ivermectin is effective against COVID either do not plan to get vaccinated or are unsure about the vaccine. But unlike the data supporting vaccines, Griffin says, the evidence behind that use of ivermectin is questionable and unclear. He worries not only that the hype over the antiparasitic drug may keep some people from getting vaccinated but also that sick people taking it at home might delay going to a hospital and miss the efficacy window for evidence-based COVID treatments.
Nevertheless, ivermectin prescriptions are soaring, topping 88,000 a week in the U.S. last month (compared with an average of 3,600 per week in 2019). Although the form of the drug sold in pharmacies is routinely prescribed for U.S. Food and Drug Administration–approved uses such as treating parasitic infections, the doses and schedules that the FLCCC posts on its Web site are not consistent with those typically advised for humans. Cedric Dark, an emergency physician and professor at Baylor College of Medicine, says ivermectin is usually given as a one-time dose when it is used as a parasite treatment. In contrast, the FLCCC’s prevention protocol suggests taking it “twice a week for as long as [COVID] risk is elevated in your community.” But Griffin explains that “we do not have reliable safety data on the prolonged courses being recommended currently or in patients taking ivermectin while suffering from COVID-19 and all the immune and metabolic changes associated with this disease.”
Ivermectin was not the first drug the FLCCC endorsed for treating COVID. Paul Marik, a critical care physician and professor at Eastern Virginia Medical School, helped found the organization. In 2016 he had begun giving what became known as the “Marik cocktail” for treating sepsis, a life-threatening reaction to an infection that triggers inflammation throughout the body. The intravenously deliveredcocktail contains a high dose of vitamin C, the steroid hydrocortisone and vitamin B1. A randomized trial ultimately showed the cocktail was ineffective for sepsis. But when the pandemic hit, Marik began trying it on patients with COVID. In April 2020 he, Kory and a few of their colleagues formed the FLCCC to encourage the adoption of a modified cocktail that they thought could work for the disease. And in late 2020 the group added ivermectin to its protocols.
Much of the public interest in ivermectin as a treatment and prophylactic for COVID can be traced to a study led by Australian scientist Leon Caly that was in the spring of 2020. In that work, scientists added very high concentrations of the drug to cells grown in petri dishes and reported that it prevented the virus that causes COVID from making copies of itself. Similar studies in the past have indicated that ivermectin has antiviral properties when added to lab-grown cells: it blocked replication of viruses that cause dengue, Zika, West Nile, AIDS and other diseases. Prior to the pandemic, however, only one clinical trial had evaluated ivermectin specifically for a viral illness (dengue fever), and it showed no clinical benefit.
Nevertheless, clinical trials testing ivermectin for preventing or treating COVID began, “driven by a very generous motivation to try to find inexpensive cures that are going to prevent people from dying [of COVID],” says public health expert Howard Forman of Yale University. But the trials used different doses on different schedules, Dark says, “which makes it very difficult to compare one to the next.”
Furthermore, he says, many of the ivermectin studies have design flaws that preclude them from leading to changes in clinical practice. A report published in July by Cochrane, a highly regarded independent organization that reviews medical research and helps guide clinical practice, looked at dozens of studies on ivermectin, of which only 14 qualified for evaluation. The report excluded 38 investigations because of problems with their methodology: they either had no control group, an inappropriate control group or other kinds of biases. The 14 remaining studies, which included a total of 1,678 participants, did not support the use of ivermectin for preventing or treating COVID, the report concluded.
In contrast with ivermectin, the evidence of COVID vaccines’ effectiveness is “incredibly compelling,” Griffin says, and the majority of COVID deaths and hospitalizations are vaccine-preventable.
Yet the groups promoting ivermectin do not appear to strongly support the COVID vaccines. The FLCCC says little about them on social media and writes in the current version of its prevention protocol that ivermectin is a “safety net” for those who are not vaccinated (although that protocol adds, “Vaccines have shown efficacy in preventing the most severe outcomes of COVID-19”). AFLDS founder Simone Gold, a doctor who was arrested for activities related to her involvement in the January 6 insurrection at the Capitol and is connected to a conservative political group, and Tess Lawrie, director of a company called the Evidence-Based Medicine Consultancy and organizer of the BIRD Group, have even shared vaccine misinformation in videos online. And AFLDS also gives advice on vaccine exemptions on its Web site.
Additionally, the AFLDS Web site suggests—without evidence—that there is some nefarious reason that vaccines are heralded while cheap drugs and dietary supplements (such as ivermectin, hydroxychloroquine, zinc, vitamins and antibiotics) are not. The FLCCC, too, has alluded to a conspiracy in a tweet: “The FDA, the CDC, major media & others hope you’ll believe them when they tell you that [ivermectin] was meant only for animals, & that it’s dangerous to use for [COVID].”
Heidi Larson, director of the Vaccine Confidence Project at the London School of Hygiene & Tropical Medicine, calls this approach “a classic tactic to undermine confidence in authority.” She adds that such “manipulation is really a core strategy across the groups that are trying to undermine confidence in vaccines.”
Dark points out that a cheap, widely available drug is used to treat symptoms of COVID: a steroid called dexamethasone. When a well-designed clinical trial showed that dexamethasone helped certain patients hospitalized with COVID, it was widely adopted by physicians. Griffin says the anticoagulant medication heparin is another example of a cheap drug being used in hospitals to help treat COVID patients.
Ivermectin can be a moneymaker, too. AFLDS charges $90 for telehealth visits with doctors willing to write off-label prescriptions for ivermectin or hydroxychloroquine—another highly touted drug that was found to be ineffective and sometimes harmful—for treating COVID. And AFLDS connects people with a digital pharmacy that will fill those prescriptions or send them to a local pharmacy, sometimes for exorbitant prices. Contacted for this story, the group declined to comment on these practices. The FLCCC also curates a list of pharmacies that will fill off-label ivermectin prescriptions, and it offers a list of physicians who use the group’s protocols. The organization did not respond to requests for comment, including on whether it earns money through these services.
Despite claims of a conspiracy against ivermectin, Griffin points out that researchers are continuing to study it and other repurposed drugs for COVID. There are at-home randomized placebo-controlled clinical trials underway, including the COVID-OUT trial, the ACTIV-6 study and the U.K.-based PRINCIPLE trial.
“I would love for ivermectin to work. Just prove it,” Forman says. But even if we have an effective treatment for a disease, that does not negate the need for a vaccine, Larson says. “We need all the tools in the toolbox,” she adds.
Fringe Doctors' Groups Promote Ivermectin for COVID despite a Lack of Evidence
The organizations touting unproved protocols for the antiparasitic drug may be harming vaccination efforts
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Merck says experimental pill cuts worst effects of COVID-19
Study tracked 775 adults with mild-to-moderate COVID-19 considered higher risk for severe disease.
Merck & Co. said Friday that its experimental COVID-19 pill reduced hospitalizations and deaths by half in people recently infected with the coronavirus and that it would soon ask health officials in the U.S. and around the world to authorize its use.
Study tracked 775 adults with mild-to-moderate COVID-19 considered higher risk for severe disease.
Merck & Co. said Friday that its experimental COVID-19 pill reduced hospitalizations and deaths by half in people recently infected with the coronavirus and that it would soon ask health officials in the U.S. and around the world to authorize its use.
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【新冠肺炎】年底申請口服解藥上市許可 日藥廠塩野義：2022讓百萬人受惠
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日文原文：
塩野義製薬は29日に東京都内で記者会見を開き、開発を急ぐ新型コロナウイルスの治療用の飲み薬について、2021年中の承認申請をめざすと明らかにした。手代木功社長は「可及的速やかに実用化する」と表明。22年3月までに国内で100万人分を生産するとも語った。
【新冠肺炎】年底申請口服解藥上市許可 日藥廠塩野義：2022讓百萬人受惠--上報
新型病毒引發的肺炎（COVID-19）持續擴散，截至29日16時，全球確診病例為2億3359萬2026例，累計死亡人數達4......
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日文原文：
塩野義製薬は29日に東京都内で記者会見を開き、開発を急ぐ新型コロナウイルスの治療用の飲み薬について、2021年中の承認申請をめざすと明らかにした。手代木功社長は「可及的速やかに実用化する」と表明。22年3月までに国内で100万人分を生産するとも語った。
