I didn’t think I would write this week about chloroquine and SARS-CoV-2. I wasn’t really planning on doing a sequel (lets be honest, the only sequel that doesn’t suck is Predator 2, because Danny Glover), and there are already so many people cautioning us against taking this drug as a reliable therapeutic strategy to deal with COVID-19, without undergoing further tests. Well, it seems that the FDA thinks otherwise, and has approved chloroquine for treatment of COVID-19 (1, 2).
I’ll say the same thing I said last week. We still don’t know if chloroquine can treat COVID-19 and maybe we should be really sure before start using a drug that has a bunch of unpleasant side effects. We have a lot of data from in vitro experiments that shows chloroquine (in conjunction with other drugs) messes up the ability of the virus to replicate itself. That much is clear. But those are observations from cells that are sitting in a glorified petri dish. The next stage, trials in human beings, is underway, and things are a little bit less clear.
There are two papers that detail clinical trials in human beings using chloroquine in conjunction with azithromycin to treat infection with SARS-CoV-2, both authored by Didier Raoult.
There’s no good, the bad and the ugly. Both state that chloroquine could be used to treat COVID-19, with good outcomes. So far, so good. However, science, much like life, is not a spectator sport. Soon enough other researchers were looking at the work done by Raoult, and taking issue as how the good doctor went about doing things (3, 4). What they are saying is that the first study is deeply flawed, there are technical issues with the way the data was gathered and the authors dropped patients from the group that was receiving chloroquine because they did not show the preferred outcomes. Furthermore, it does appear the study was initiated without the proper ethics permissions, and the cherry on top of this weird cake is the fact that the editors of the journal where this paper was published are among the list of authors. This is a major conflict of interest and even casts doubt on if the manuscript was reviewed at all by other scientists, before publishing, given that it was published 24 hours after submission. Usually takes a bit longer…
The second study has attracted more of the same criticism. Results that are illogical (such as the treatment curing patients overnight), being called an observational study when the authors are actively intervening (by giving chloroquine) and the absence of a control group are some of their criticisms (5). In the end, what they are really saying is that we cannot actually say from this work that chloroquine works against SARS-CoV-2. The data is just not reliable enough.
The whole thing is a disservice to science, but the really frustrating thing is that it delays our understanding on chloroquine as a valuable tool to treat COVID-19 and further muck the waters on our response to SARS-CoV-2. Forget about arguing about the effectiveness of public health measures, now we need to convince desperate people to not take something that could potentially kill them. While they are panicking in a middle of a pandemic. Brilliant.