A cheap and widely available U.S. drug used as an antidepressant now also appears to be a lifesaving covid-19 treatment. In a newly published, large-scale clinical trial, the drug fluvoxamine was shown to reduce the risk of prolonged hospitalisation as well as death in high-risk patients treated at an emergency room. Coupled with the results of other promising trials, fluvoxamine looks poised to become part of the medical toolkit against the pandemic, which is still sickening hundreds of thousands of people worldwide every day.
Fluvoxamine is a selective serotonin reuptake inhibitor (SSRI) that’s been around since the 1980s. It’s used commonly for treating depression as well as obsessive-compulsive disorder. In addition to its antidepressant properties, fluvoxamine is known to reduce inflammation. And it’s that latter attribute that made some researchers wonder if it could be repurposed to combat or prevent severe covid-19, which is often characterised by an overzealous immune response.
Fluvoxamine is far from the only older drug that scientists have pinned their hopes on during the pandemic. But unlike many other candidates, including hydroxychloroquine, it seems to have stood up to more rigorous tests. On Wednesday night, the results of the largest covid-19 trial on fluvoxamine yet were published in the Lancet Global Health, and they look very encouraging.
The research is part of the TOGETHER trial, a joint collaboration between Canadian and Brazilian researchers to test out several older drugs that could be used early on to prevent covid-19 from worsening. The fluvoxamine arm of the trial began in January 2021 and involved around 1,400 Brazilian patients who were seen for covid-19 as outpatients at an emergency room, all evaluated to be high risk for severe illness. These patients were randomised to receive fluvoxamine or a placebo, then they were monitored for 28 days.
Overall, 15.7% of placebo patients went on to need an extended stay at the ER or hospitalisation later on, while the same was true for 10.6% of patients given fluvoxamine — about a 30% reduction in relative risk. This reduction grew to 65% for those who took the entire course of fluvoxamine as instructed, the authors said. Though deaths were low across both groups, meaning that the findings aren’t quite as definitive, fluvoxamine had an advantage there as well: Only one patient among those who took at least 80% of fluvoxamine doses died, compared to 12 in the placebo group who were similarly adherent to their treatment (overall, 17 died in the fluvoxamine group, vs 25 in the placebo group).
“Our results are consistent with earlier, smaller trials. Given fluvoxamine’s safety, tolerability, ease of use, low cost, and widespread availability, these findings may have an important influence on national and international guidelines on clinical management of COVID-19,” said Gilmar Reis, a Brazilian researcher and co-principal investigator of the TOGETHER trial, in a statement from McMaster University in Canada, one of the partners of the project.
Fluvoxamine has long since become generic and costs about $5 for a 10-day course, indicating that it could be distributed easily and affordably across the world, particularly to countries where access to more expensive covid-19 drugs like monoclonal antibodies is limited. And if it did become a standard covid-19 treatment, it would follow in the footsteps of dexamethasone, a cheap steroid used to treat the most severe cases. Unlike dexamethasone, though, it could be widely doled out as a sort of prophylactic to keep cases from ever getting to that more serious point.
It may take other large trials for organisations like the WHO to endorse its widespread use, though there are several other upcoming studies in the wings, including in the U.S. There are also important questions left to be answered about the drug’s viability for covid-19, including its optimal dose, whether it would be used as a combination therapy with other promising drugs, and if it would help vaccinated people who develop a breakthrough infection. But the new results may be enough to compel some doctors and countries to adopt the drug. Despite the pandemic being on the wane for much of the world, including in the U.S., some countries such as Russia are battling resurgent waves, and many poorer countries still have little access to vaccination.