Susan Conroy, MD, PhD | Indiana University
Patricio Riva Posse, MD | Emory University


The Treatment Resistant Depression Task Group was formed to address the needs of patients who do not respond to currently available therapeutic interventions for depression. There remains a lot that we are yet to understand as to why some individuals respond quickly and effectively to a variety of treatments, whether behavioral, pharmacologic or neuromodulatory; and yet others do not. Or why some respond for a while, and then over time, stop receiving therapeutic benefit from those treatments that were once effective.

In the current era of ‘precision medicine’ we are far better placed than ever before to resolve these important issues. Towards this, our Task Group, together with the NNDC Biomarkers Task Group, is embarking on a collaborative project specifically aimed at identifying why some patients respond to a specific treatment, while others do not. By combining our expertise, resources and treatment trials across Centers within the Network, we are optimally placed to identify and develop biomarkers that can be used to individualize treatment plans for our patients – helping to get the best therapy to each individual patient faster and avoid the current (mostly) ‘trial and error’ process.

TRD Atlanta meeting picture

July 2018 TRD Project Meeting in Atlanta, GA  (pictured left to right:  Dr. Cheryl McCullumsmith, Dr. Patricio Riva Posse, Dr. William McDonald, Dr. Jesse Wright, Dr. John Greden, Dr. Joao De Quevedo, Dr. Sudhakar Selvaraj, Dr. Sudheep Virk)


Depression is a chronic and severe psychiatric illness that affects over 15 million people in the United States and by 2020 is expected to be the leading cause of disability worldwide. Unfortunately, up to a third of patients do not respond to currently available treatments, and are considered to have treatment-resistant depression (TRD). Compared with treatment-responsive depression, TRD is associated with a more chronic and severe illness course, progressively detrimental effects on brain structure and functioning, increased healthcare costs, and risk of premature death by medical illnesses and suicide. As we better understand the medical underpinnings of depressive illness, we are increasingly appreciating that treatment-resistant forms of this illness have a distinct pathology from treatment-responsive forms. Our Task Group is actively involved in development of treatment, research and educational strategies aimed at helping to understand these differences, close the gap on non-response and personalize treatments for TRD.


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Researchers from our current member institutions should contact Diana Burnett, Program Manager ([email protected]), for more information about being added to the task group.

We are not accepting non-affiliated researchers at this time to our Task Groups. We do, however, encourage researchers who are not from our member institutions to talk to their current institutional leadership about becoming a member of our Network. More information about joining the NNDC can be found on our membership opportunities page: