FDA has approved the first ketamine-based antidepressant

Doctors have a new weapon in the fight against particularly pernicious depression: a drug based on the powerful anesthetic ketamine.

The drug — called Spravato and developed by Janssen Pharmaceuticals, Inc. — was approved on March 5 by the U.S. Food and Drug Administration as a treatment for severely depressed people who haven’t responded to two courses of other treatments. The first ketamine-based antidepressant, Spravato is a nasal spray that must be delivered in a doctor’s office, and is intended to be used in addition to an oral antidepressant.

Ketamine is an anesthetic that’s been in use for decades; it is also an illicit drug, known as “Special K” or “Vitamin K,” that can create out-of-body psychedelic hallucinations. Other antidepressants often take weeks to kick in, but ketamine and related compounds work within hours or days for some people. Some patients experienced the effects of Spravato in two days, a clinical trial found.  

Ketamine is a mixture of two mirror image molecules. Spravato is composed of one of those molecules: esketamine. It’s not yet clear how esketamine compares with ketamine in its ability to ease depression. Other researchers are testing the antidepressant effects of other ketamine relatives, as well as one of ketamine’s breakdown products (SN: 5/28/16, p. 13). And promising early research has led some doctors to begin administering ketamine to people who have shown no improvement from other treatments for severe depression. But large clinical trials and a deeper understanding of side effects are still needed.