The medical world was buzzing after data on the drug remdesivir was published in the New England Journal of Medicine showing that 68% of COVID patients treated with remdesivir improved. Now we’re seeing reports from all over the place - CNN, the New York Times, Axios - touting the “promise” and “encouraging signs” of this medication in preliminary data from another clinical trial.
Gilead, the company that makes this drug, has unsurprisingly seen a bump in its stock after these reports.
What is remdesivir?
Remdesivir is a broad spectrum antiviral drug that works by blocking viral replication. In an isolated lab setting, it has demonstrated effects against multiple different virus families, including filoviruses like Ebola and corona viruses like SARS, MERS, and SARS-CoV-2 (the virus responsible for COVID-19). Remdesivir seems to reduce lung injury in both mice and macaques infected with MERS. It also has effectiveness in test tubes against SARS-CoV-2.
The medical term for the effects that it has blocking the virus in a lab setting is “in vitro,” which basically means that it happens outside of a living organism. Lots of compounds have in vitro effects that don’t pan out when we study them in actual humans with actual diseases.
This is why we do randomized clinical trials in medicine - because what makes biologic sense based on our predicted models doesn’t always pan out when we put it to the test in real life.
All models are wrong, but some models are useful.
Indeed, when remdesivir was studied in real Ebola patients, it was actually removed from the trial protocol during an interim analysis because it was less effective than the other treatments being tested.
Tell me about the recent trial showing improvement in 68% of remdesivir patients
The COVID patients treated with remdesivir in the recently published NEJM trial were patients approved for use of the drug by Gilead on something called a “compassionate use” basis. This was a group of 53 patients with an average age of 62. They were required to have a need for oxygen support, and they couldn’t have any evidence of kidney or liver failure. In other words, sick enough to need hospitalization and respiratory support, but fairly young and not having failure of any other organ system. About 25% of them had diabetes and about 17% had hypertension.
Important to note that in this study, remdesivir was not compared to a placebo. This is a report of what happened to the patients who received remdesivir, NOT a comparison of this treatment to any others. And keep in mind that all patients needed to be approved by Gilead before receiving the drug.
The investigators found that 36 of the 53 patients (68%) had improvement in oxygen needs while 15% got worse in this area. There was a lot of attention paid to the fact that the sickest patients (30 who were intubated and 4 who were on ECMO) had decent outcomes, with 17 of the intubated patients having breathing tubes removed and 3 of the ECMO patients stopped receiving it.
But hold your horses: the fact that there’s no comparison in this trial means that we have no idea whether patients got better because of remdesivir or in spite of it.
What about this new report?
According to STAT news, where this update was first reported, they’re seeing great effects from remdesivir given to 113 patients with severe disease. However, buried deep in the article there’s evidence that you should take these results with a huge grain of salt. Take a look at this quote from the lead investigator at University of Chicago, where these patients were treated:
“It’s always hard,” she said, because the severe trial doesn’t include a placebo group for comparison. “But certainly when we start [the] drug, we see fever curves falling,” she said. “Fever is now not a requirement for people to go on trial, we do see when patients do come in with high fevers, they do [reduce] quite quickly. We have seen people come off ventilators a day after starting therapy. So, in that realm, overall our patients have done very well.”
Not to sound like a broken record, but until there is a randomized trial where remdesivir is being compared to a placebo, we just don’t know whether patients got better because of remdesivir or in spite of remdesivir.
So what will the randomized trial tell us?
Gilead is currently enrolling 2,400 patients in a randomized, placebo controlled trial. After the initial paper came out showing results from patients receiving remdesivir, there were some changes to the trial protocol, which a cynic would interpret as standard pharma funny business.
The bottom line is that we don’t know anything until the trial results come out. Remdesivir might work, but it also might make things worse. When it was properly studied in Ebola, results weren’t particularly encouraging. When hydroxychloroquine was studied compared to placebo in COVID-19, it seemed to have no benefit but had increased side effects.
We do trials to test hypotheses, and right now all we have about remdesivir are hypotheses. I don’t think I’m ready to recommend using your stimulus check on Gilead stock until we get actual data from a true randomized trial.