A nasal spray version of esketamine was more effective for depression that is resistant to treatment than a more commonly used drug, research published Wednesday in The New England Journal of Medicine found.

Esketamine is a more potent form of ketamine, an anesthetic that doctors have used for many years to treat depression. The nasal spray, from Janssen Pharmaceuticals, is sold under the name Spravato and was approved by the Food and Drug Administration for treatment-resistant depression in 2019. Janssen funded the new study, which took place in 24 countries across Africa, Asia, Europe and South America.

“Treatment-resistant depression is a pretty significant problem,” said Dr. Michael Grunebaum, an associate professor of psychiatry at Columbia University Medical Center in New York City and a research psychiatrist at the New York State Psychiatric Institute.