I had an exchange on Twitter with people alleging that doctors are finding that the drug hydroxychloroquine is 100% effective against COVID-19 and posting videos of patients claiming they had been cured by this drug. I tried to explain that this evidence is not valid and provided a link to one of my previous posts that addressed these claims. Then I stated that we need to wait for the results of the clinical trials. The response I got was that if doctors and their patients have tried it and are convinced it works, then that’s all the evidence we need.
Unfortunately, this is simply not true. Even before hydroxychloroquine came along, the majority of patients hospitalized with COVID-19 would survive. If all patients are treated with hydroxychloroquine, then how do we know which patients got better because of the drug and which got better because they were going to get better anyway, or because of other treatments? In an uncontrolled clinical environment in the middle of a pandemic, patients are not randomized into matched groups and their treatments controlled and blinded to exclude placebo effects and other biases. Patient testimonials and doctor’s opinions are valuable to design clinical trials, but they have many shortcomings and should never be used to establish whether a drug works or not. All doctors know (or should know) this.
However, the main point of this post is not to address the claim that hydroxychloroquine is 100% effective against COVID-19, but rather the attitude of scientists towards such claims, especially when they are reported using the media instead of the regular scientific channels.
Scientists know that products or therapies that are 100% effective are rare, and this is even more so in the case of major diseases like COVID-19. Some vaccines, hormones like insulin, or a few antibiotics have approached this level of effectiveness, but this is not very common for most other compounds or drugs. About 86% of the drugs tested in clinical trials are found not to be effective and are not approved. Claims of 100% efficacy for a drug or therapy will trigger a strong (and warranted) skeptical response from most scientists.
I have been around a while, and I have read many investigations into multiple bogus claims regarding miracle cures or procedures promoted by quacks. One of the characteristics of these individuals is that they inflate the claims they make regarding the efficacy of their products or therapies beyond the bounds of credibility. If these fraudsters wanted to be believable, they would probably look up the percentage cure rate of the best science-sanctioned therapy and then inflate the claims for their products or therapies by a few percentage points to make them look significantly better but not impossibly so. However, the target audience of these individuals is not scientists but the general public, which has no experience with scientific research or clinical trials and their nuances.
As I have explained before, the best way to promote a bogus product or therapy is to make your audience assimilate your product as part of their identity. If you can achieve this, your audience will be impervious to evidence that the product does not work. This is because any attack on your product will be viewed by the members of your audience as a personal attack on themselves. From this vantage point, it is unfortunate that the president of the United States has promoted the use of hydroxychloroquine. In the current politically charged atmosphere, I am concerned that this identity-forming process seems to be coalescing around the notion that if you don’t accept that hydroxychloroquine works, then you are against the president and thus part of a left-wing conspiracy. It is then all too easy for unscrupulous individuals to exploit this situation by linking themselves to the “pro-president” audience and peddle hydroxychloroquine or other as yet unproven drugs or therapies for COVID-19. If their claims are questioned, all they have to do is argue they are being attacked by the same system that their audience believes is against them and the president.
I was skeptical about hydroxychloroquine from the beginning, not because the president promoted it, but because the data for its effectiveness was weak. Thus when I hear these claims for 100% effectiveness of hydroxychloroquine (or any other drug or therapy for that matter), this immediately raises a red flag, and I close my mind to them. This may not seem the scientific thing to do, but remember that keeping your mind too open can be dangerous. As far as I’m concerned, like the late astronomer Carl Sagan said, “Extraordinary claims require extraordinary evidence.”, and the burden of proof is on those individuals who make these claims. It is up to them to produce high-quality evidence to support that what they claim is true, and, seriously, with a 100% success rate this should not prove too difficult, right?
At this point you may argue that even if the effectiveness of hydroxychloroquine is less than 100%, but something like 80%, or 50% or 30%, that would still be significant and important. My answer to this is, yes, but this HAS to be established by well-designed clinical trials. At the moment, many clinical trials of hydroxychloroquine are ongoing, and several of these trials are sufficiently well-designed to yield unambiguous results. As I write this, among the best trials completed so far, one has indicated that hydroxychloroquine does not work as a prophylactic against COVID-19, and another has indicated that hydroxychloroquine does not reduce the risk of death among patients hospitalized with COVID-19. The FDA recently revoked its emergency use authorization of hydroxychloroquine, because based on the available evidence it’s unlikely to be effective in treating COVID-19 and any potential benefit from its use outweighs the potential risks.
Many of these trials were designed to address the initial claims for hydroxychloroquine being very effective when administered alone or with certain antibiotics. A new claim has been made that hydroxychloroquine is only effective when it is administered with zinc, and new clinical trials are being performed to evaluate this possibility. As I stated above, I am skeptical about hydroxychloroquine, but I don’t want to be right, I want to save lives, and I hope the combination of hydroxychloroquine with zinc works. However, the public has to understand and accept the need to perform clinical trials and stop relying on testimonials and other anecdotal evidence.
Image of a quack doctor selling remedies from his caravan; satirizing Gladstone's advocacy of the Home Rule Bill in Parliament is a Chromolithograph by T. Merry, 1889, and comes from the Welcome Collection. The image was modified and used here under an Attribution 4.0 International (CC BY 4.0) license, and no endorsement by the licensor is implied.