An inexpensive repurposed drug, fluvoxamine, may reduce hospital admissions in high-risk COVID-19 patients by up to 30 percent, according to a study published in The Lancet Global Health journal.

Fluvoxamine is currently used to treat mental health conditions such as depression and obsessive-compulsive disorders. It was chosen for study as a potential treatment for COVID-19 due to its anti-inflammatory properties.

Researchers treated 739 randomly selected Brazilian COVID-19 patients with fluvoxamine, with another 733 receiving a placebo, between January 15 to August 6 of this year.

Every patient who received fluvoxamine during the trial was tracked for 28 days to determine their health outcomes and if they still need hospital treatment.

The study found about a 30 per cent reduction in hospitalisations among those receiving fluvoxamine compared to those receiving the placebo.

This effect went up to 65 per cent among patients taking all of their drugs, they said.

“Fluvoxamine may reduce the production of inflammatory molecules called cytokines, that can be triggered by SARS-CoV-2 infection,” said Angela Reiersen, Associate Professor at Washington University in the US, and co-author of the study.

In a secondary analysis of patients who took at least 80 per cent of medication doses, there was one death in the fluvoxamine group, compared to 12 in the placebo group.

The fluvoxamine trial formed part of the larger TOGETHER Trial that started in May 2020, aiming to test potential COVID-19 treatments in a community setting.

“Fluvoxamine is, so far, the only treatment that if administered early, can prevent COVID-19 from becoming a life-threatening illness,” said Edward Mills, co-principal investigator for the TOGETHER Trial and a professor at McMaster University in Canada.

“It could be one of our most powerful weapons against the virus and its effectiveness is one of the most important discoveries we have made since the pandemic began, Mills said.

Costing about four dollars per 10-day course, fluvoxamine could be a game-changer for poorer countries with low vaccination rates and lacking access to more advanced COVID-19 therapies, he added.The researchers noted that fluvoxamine has been used since the 1990s for various conditions and its safety profile is well-known.

It was identified early in the pandemic for its potential to reduce the cytokine storm in COVID-19 patients.

Cytokine storms are severe immune responses to COVID-19 that can cause potentially lethal organ damage.

The authors acknowledge some limitations in their study.

They noted that although fluvoxamine is widely available, it is not on the World Health Organisation (WHO) Essential Medicines List.It is crucial to establish if these drugs can be used interchangeably for COVID-19, as well as determining whether combining fluvoxamine with other drugs will provide a larger treatment effect, the researchers said.

They also noted that the use of interventions, including fluvoxamine, to prevent progression of illness and hospitalisation is critically dependent on reliably identifying individuals at highest risk of deterioration in the early stages of COVID-19 infection.

“Despite the important findings from the TOGETHER trial, some questions related to the efficacy and safety of fluvoxamine for patients with COVID-19 remain open,” said Otavio Berwanger of the Academic Research Organisation of Hospital Israelita Albert Einstein, Brazil, who was not involved in the study.

“The definitive answer regarding the effects of fluvoxamine on individual outcomes such as mortality and hospitalisations still need addressing,” Berwanger added.