Clinical Study IDs Potential Antidepressant Predictor

(National Institute of Mental Health)

Researchers at Loyola University Medical Center near Chicago have found a method that can help predict if an antidepressant will work on a patient with depression. Loyola psychiatry professor Angelos Halaris and colleagues reported their work earlier this year at the annual meeting of the Society of Biological Psychiatry.

The study involved 35 patients who took escitalopram for major depressive disorder. Escitalopram is marketed by Forest Laboratories under the brand name Lexapro, and belongs to a class of antidepressants called selective serotonin reuptake inhibitors (SSRIs). Other common SSRIs are Prozac, Paxil, and Zoloft.

Halaris’s study found that among depressed patients who have higher than normal blood levels of a protein called vascular endothelial growth factor (VEGF), more than 85 percent experienced partial or complete relief from depression after taking escitalopram. By comparison, fewer than 10 percent of depressed patients who had low levels of VEGF responded to the drug.

SSRIs are believed to help regenerate brain cells in specific parts of the brain that have atrophied in depressed patients. Halaris’s findings support this idea; It appears that escitalopram, the SSRI used in the Loyola study, encourages the growth of brain cells that have become inactive.

This regeneration of brain cells is fueled by VEGF. In the brain, VEGF stimulates the growth of blood vessels and works in other ways to keep brain cells healthy and active. Patients with higher levels of VEGF appear to have more regeneration helping to reduce depression, while patients with less VEGF seem to have less.

If confirmed by further studies, the findings could lead to a blood test that would help physicians tailor treatment. For patients found to have low levels of VEGF, for example, physicians might skip SSRIs and try alternative classes of antidepressants. A VEGF blood test would likely be expensive, says Halaris, but the cost likely would come down if a VEGF test were to become widely used.

Read more: Institutions, Companies Form Psychiatric Trial Database

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