@jbcarioca ...
I believe we're in a bit of a "perfect is the enemy of good" situation right now with no "perfect" studies to draw upon and yet a fair amount of data that is less than perfect and people RIGHT NOW having to make life or death decisions about whether to use the drug. While it may be dangerous to use a drug with known side effects it is also dangerous to not use that drug if it offers sufficient promise when the patient is facing a 10-27% chance of death if the decision is made to not use the drug.
Thanks for your comments. I do have one substantive reason why any use of HCQ in this context is fraught. Because of the role this drug and similar ones have in malaria prophylaxis it has been studied extensively. It is cheap and readily found almost everywhere so it is frequently imagined as a possibility for treatment of other diseases. In anti-malarial use the doses are very small, usually for limited periods and typically prescribed to people who are in good health, who travel within malaria-infected areas.
The problems come in two areas. Dosage itself and toxicity that itself increases with higher dosage and /or longer use.
I am not quoting any of the copious numbers of clinical trials and other testing that have been done over the years. Anybody who wants to can find dozens and dozens such evidence.
Summarizing typical conclusions, the present of co-morbidities (with whatever was the topic) invariably tends to increase negative side effects. Among the diseases that, if present, tend to stop prescribing almost any quinine-based medication are diabetes, hypertension, coronanary or pulmonary diseases, among others. Those categories tend to be the most common co-morbidities with CIVID-19, according to the anecdotal reports thus far.
In a couple of the most often cited favorable results it seems probable that successful results might well have been due to low risk of severe symptoms anyway. Nothing anyone has cited provide solid evidence to presume that prescribing this stuff is worth the risk, unless some controlled testing can show that the results are worth the risk of the damage caused.
I am quite intentionally not quoting any of the studies, exactly because none of them have been on point.
One of the most common errors non-statisticians is to say something like"I know this is not statistically valid, but it certainly is directionally correct" (that is in quotes because it is a verbatim quotation from a highly educated colleague of mine on another subject entirely.) Sadly, anecdotal observations are, by definition NEVER justification for trying something with known toxic reactions in search for treatment for something which has low mortality risk. If the patient is near death and a physician has no known treatment, clinical trials and even experimentation might be justified. Otherwise such use is unwise and might be illegal.
I hasten to add that off-label use of many drugs is common and warranted which the known risks are well documented and considered. That is NOT what this one is.
This one is getting clinical trials because politicians are promoting it in several countries. The politicians know nothing at all about their subject and less about potential death that might result from rushing this stuff to common use. They want a panacea and this ain't a panacea!
Right now there are many hundreds of serious professional efforts to develop treatments, cures, vaccines all using data that considers the genetic structure and composition of SARS-CoV-2 as well as the full character of COVID-19. These are not off-the-cuff guesses by a GP somewhere nor have they much political support. Some of these things are already undergoing trials. Some positive developments are happening, we'll hear about them as they yield results, probably long before there are actual applicable tools.
In the meantime uninformed speculation is exciting and hopeful, but really is depressing because the hope is false. Worldwide people are pushing things that are close to 'snake oil'. We desperately want these to be true.
So why have so many been pushing these quinine versions? That answer is too painful. Those who began to push it were those who had it on hand, they have been desperate too, so they used what they had. If they used it on people who would have recovered anyway it rarely would cause too much harm. Then, it would seem to be the cause of success when it really was something that was applied to someone who was going to recover anyway. So, maybe this paragraph is wrong. We cannot know because there were no controlled tests.
There is no shortcut to exhaustive testing. Remember thalidomide? That one is an excellent drug that is invaluable in treatment of several cancers, for example, but it should NEVER be given to a pregnant woman. Only careful and exhaustive testing can establish whether a given drug will have invaluable benefits or catastrophic side effects. If it is like thalidomide the same drug has both of those, depending on how it is applied.
So, if a politician says, "what do you have to lose?", there is an answer: your life.