Tagging the lows: RNA markers personalize depression treatment

King's College London researchers says inflammation markers are key to treating depression--Image courtesy of King's College London.

There are currently no approved blood tests to diagnose depression or to help doctors select the right drugs for their patients. However, a team at King's College London's Institute of Psychiatry (IoP) has found a new panel of markers that could predict people's response to treatment, saving them from a "trial and error" process.

"The study shows that we could use a blood-based 'test' to personalize the treatment of depression," says Carmine Pariante of the IoP in a statement.

The study is part of the Genome-Based Therapeutic Drugs for Depression (GENDEP) project, and the researchers say that it is the first to identify blood biomarkers for antidepressant response in a controlled clinical study. The aim was to find mRNA biomarkers that predict response to treatments, and also that track treatment response.

The researchers looked at patients treated with one of two standard antidepressants--escitalopram or nortriptyline--and found that the people who did not respond well to treatment showed higher levels of three inflammation biomarkers, suggesting that these could be used to predict drug response.

The patients who responded well had lower levels of a different inflammation biomarker, as well as a glucocorticoid receptor function marker, and higher levels of two neuroplasticity markers. That could mean that the levels of inflammation markers may be able to track the level of response in some patients.

The study also supports the idea that inflammation is part of the mechanism leading to some forms of depression, and that targeting this could help hard to treat forms of the disease. Recent research showed that Janssen's Remicade (infliximab), a drug designed to treat inflammatory disorders, could help some cases of depression.

However promising the results, this is still a small study, and further work will be needed to develop a test that could personalize the treatment of depression.

- read the press release
- see the abstract