Meet Viibryd, the newest antidepressant to be approved by the Food and Drug Administration (FDA) for major depressive disorder. Some market analysts are already predicting potential annual sales in excess of $1 billion for the new pill. Why? For one thing, in clinical trials, it led to fewer sexual side effects than may be commonly seen with other depression drugs.
The L.A. Times‘ Booster Shots blog reports on the makeup of the new medication:
The drug, called Viibryd (or vilazodone), is the first antidepressant that is a selective serotonin reuptake inhibitor combined with and a 5HT1A receptor partial agonist. Many of the so-called SSRI antidepressants, such as Prozac or Zoloft, work on the serotonin system of the brain. Viibryd is a dual-mechanism medication in that it also affects the 5HT gene.
Many patients taking SSRIs like Prozac and Zoloft report loss of sexual desire, a side effect that prompts some patients to discontinue medication. In a 2009 Phase III trial of Viibryd, researchers found that the drug improved symptoms of major depression in as little as a week, with no difference in sexual functioning between people taking Viibryd and those taking placebo. (More on Time.com: Treating Depression: How Bright Light Can Help)
Weight gain, another side effect commonly reported by antidepressant users, appeared not to be a significant problem with Viibryd in trials. The most common side effects reported by patients were diarrhea, nausea, vomiting and insomnia.
However, the FDA notes that all antidepressants carry a small but serious suicide risk:
Viibryd and all other antidepressant drugs have a boxed warning and a patient medication guide describing the increased risk of suicidal thinking and behavior in children, adolescents, and young adults ages 18 to 24 during initial treatment.
The warning also says data did not show this increased risk in adults older than 24, and that patients ages 65 and older who take antidepressants have a decreased risk of suicidal thinking and behavior.
Viibryd’s maker, PGxHealth, a division of Clinical Data Inc., is hoping that the drug’s approval will eventually be expanded to the treatment of other conditions, such as anxiety disorders.