Treatment-resistant depression affects 1 in 3 of the estimated 16.2 million adults in the U.S. who have suffered at least one major depressive episode. For them, two or more therapies have failed and the risk of suicide is much greater. It’s a grim prognosis.

There are few therapies for depression that resists treatment, which is why the FDA granted this new drug application Fast Track and Breakthrough Therapy status. On March 5, the Food and Drug Administration approved a new treatment c