Fluvoxamine Antidepressant May Reduce Risk of Severe COVID-19, Trial Suggests

Ever since the COVID-19 pandemic began, scientists have searched for an easily accessible medication that can help treat the virus. Merck recently announced that it is planning to seek an emergency use authorization from the Food and Drug Administration for its antiviral, molnupiravir. And now, it seems, there’s another promising—but surprising— medication that may be helpful in keeping high-risk patients out of the hospital: the antidepressant fluvoxamine.

A large, placebo-controlled, randomized clinical trial published in The Lancet on Wednesday analyzed the effects of the drug, which is currently used to treat obsessive-compulsive disorder and depression, on patients with COVID-19. The researchers randomly assigned 741 patients fluvoxamine and 756 were given a placebo. The researchers discovered that the group that was given fluvoxamine were 1/3 less likely to need to be hospitalized or undergo prolonged medical observation than the placebo group.

Some patients with COVID-19 stopped taking fluvoxamine over side effects but, in those who continued with the medication, one patient died compared to 12 who were given the placebo. Fluvoxamine also lowered the risk of patients being hospitalized by 2/3.

The study was eventually stopped “for superiority,” meaning it was halted because fluvoxamine was deemed effective in groups that were given the medication.

There are a lot of questions surrounding fluvoxamine and COVID-19 based on these results, and fair. Here’s what you need to know about this readily available medication and why it might help fight severe complications from COVID-19.

What is fluvoxamine?

Fluvoxamine is a selective serotonin reuptake inhibitor (SSRI) approved by the FDA to treat obsessive-compulsive disorder, according to the National Institutes of Health (NIH). It’s also used to treat other conditions like anxiety and depression, says infectious disease expert Amesh A. Adalja, M.D., a senior scholar at the Johns Hopkins Center for Health Security. However, the NIH points out, fluvoxamine is not currently FDA-approved for the treatment of any infection, including COVID-19.

What does the data say?

The Lancet study isn’t the first to suggest that fluvoxamine may help fight COVID-19. Data published in JAMA from a randomized, double-blind, placebo-controlled trial of 152 patients with mild COVID-19 that also found fluvoxamine was beneficial. For the trial, 80 were given fluvoxamine and 72 were given a placebo. At the end of the trial, five people in the placebo group and one in the fluvoxamine group were hospitalized. However, only 76% of the participants actually finished the study and 20% of the stopped responding to the electronic survey. “Due to the study’s reliance on participant self-reports and missing data, it is difficult to draw definitive conclusions about the efficacy of fluvoxamine for the treatment of COVID-19,” the NIH says.

Another study, this one observational, analyzed the effect of fluvoxamine on people with mild forms of COVID-19. Those patients were given the option of taking 50 milligrams of fluvoxamine twice a day for 14 days or nothing. Of the 113 people who were offered fluvoxamine, 65 took the medication. More of the patients in that group had symptoms of the virus, the researchers noted. At the end of the 14-day trial, none of the patients who took fluvoxamine had symptoms of COVID-19, while 60% of those who did not undergo treatment did. None of the fluvoxamine patients were hospitalized and six of those who did not take the medication were.

Why might fluvoxamine work against COVID-19?

It’s not entirely clear at this point. The NIH points out that fluvoxamine has anti-inflammatory effects. Specifically, it’s been found to bind to a specific receptor in immune cells, lowering the production of cytokines, which are small proteins released by cells as part of your body’s immune response and inflammation.

Still, “it’s not clear what the mechanism of action is,” says Thomas Russo, M.D., professor and chief of infectious disease at the University at Buffalo in New York. Fluvoxamine isn’t an antiviral medication, and Dr. Russo points out that “early on, antivirals make a little more sense for treatment of a virus like COVID-19 because they tamp down on replication.” (If a virus can’t replicate, it won’t spread and continue to make a person sick, he explains.) “But it’s often when people get more severely ill that anti-inflammatories help,” Dr. Russo says.

Still, Dr. Russo says, “the data is intriguing.” Dr. Adalja agrees. “There appears to be a real signal that merits more consideration as an inexpensive and readily available oral medication that decreases hospitalization risk significantly,” he says. That “would be very welcome as specific antivirals are likely months away,” he adds.

Again, fluvoxamine isn’t currently recommended for use as a treatment for COVID-19, but Dr. Adalja says that could change. “It will be important for the NIH and Infectious Diseases Society of America to assess the evidence and provide recommendations for use,” he says.