A cheap antidepressant could help treat incurable brain tumours, early studies show

A cheap antidepressant drug may be able to treat a particularly aggressive, currently incurable brain tumour, Swiss scientists found in early lab research.

There are few treatments for glioblastoma, a common, fast-growing brain tumour that kills most patients in 12 to 18 months. In general, brain cancer is difficult to treat because the blood-brain barrier – a layer of cells that act as a filter between the central nervous system and the rest of the body – makes it hard for medicines to get through to the tumours.

For the new study, researchers from the University Hospital Zurich (USZ) tested 132 drugs on cancer tissue from glioblastoma patients who had recently undergone surgery, paired with computer modelling and lab mice studies.

They were mainly looking at medicines that can cross the blood-brain barrier, including antidepressants, Parkinson’s drugs, and antipsychotics.

In the tests, the antidepressant vortioxetine performed best and was “exceptionally consistent,” according to the study, published in the journal Nature Medicine. In the cancer cell tests, vortioxetine was effective at fighting the tumours for 66.7 per cent of the patients.

“The advantage of vortioxetine is that it is safe and very cost-effective,” Dr Michael Weller, a study co-author and director of the neurology department at USZ, said in a statement.

Researchers are now preparing for clinical trials to see how well the drug works in humans. In one study, patients will get vortioxetine on top of standard care such as surgery, chemotherapy, and radiation, while in the other, they will get a more personalised regimen.

In the European Union, vortioxetine is sold under the brand name Brintellix by Danish drugmaker Lundbeck. It’s been approved to treat major depression in the EU, Switzerland, the United Kingdom, and the United States.

That means if the clinical trials are successful, the drug “doesn’t have to undergo a complex approval procedure and could soon supplement the standard therapy for this deadly brain tumour,” Weller said.

The study is the latest to suggest that antidepressants could help tackle brain cancer. In 2021, for example, mice studies in the US found that fluoxetine, commonly known as Prozac, may be able to target glioblastoma.

Fluoxetine – as well as the drugs paroxetine and brexpiprazole – also seemed effective in the USZ study, though vortioxetine was by far the top candidate.

Despite the promising results in early studies, though, the jury is still out on whether antidepressants will meaningfully improve outcomes for brain cancer patients.

According to a Swedish analysis published earlier this year, patients with high-grade brain tumours, such as glioblastoma, had worse survival rates if they took selective serotonin reuptake inhibitors (SSRIs), a class of antidepressants that includes fluoxetine and vortioxetine.