{
  "id": 16057810,
  "title": "New biological marker could end trial and error in depression care",
  "url": "https://urgent.news/2026/10/22/new-biological-marker-could-end-trial-and-error-in-depression-care",
  "topic": "health",
  "section": "Health & Medicine",
  "published": "2026-10-22T14:00:21.000Z",
  "source": {
    "name": "PsyPost",
    "slug": "psypost",
    "url": "https://www.psypost.org/blood-test-could-predict-if-an-antidepressant-will-work-for-you/"
  },
  "original_language": "en",
  "account": "Major depressive disorder often requires trial and error treatment, but a new blood test could change that. Researchers identified a circular RNA molecule in blood that predicts whether a patient will respond to SSRIs, a common class of antidepressants. SSRIs work by blocking serotonin reabsorption in the brain, allowing more of the chemical to transmit messages between nerve cells. However, less than half of patients experience symptom relief after trying the first prescribed antidepressant, leading to months of trying different medications. Currently, medical professionals lack biological tests to predict which drug will work for a specific person. To find a better biological indicator, researchers investigated circular RNAs. These stable, loop-shaped genetic molecules influence how other genes operate. CDR1as, a specific circular RNA, is highly abundant in the brain and can pass through the blood-brain barrier, allowing detection through a standard blood draw. The research team found that patients who did not respond to sertraline had higher baseline levels of CDR1as in their blood, while those who experienced symptom relief had lower levels. As treatment began, patients who responded well to sertraline saw an increase in CDR1as levels, while those who did not respond saw no increase. Baseline levels of CDR1as did not predict if a patient would feel better on a placebo or go on to experience remission while taking a different antidepressant, indicating that the biomarker is specifically tied to sertraline's mechanisms. The molecule successfully identified patients who fared well on various SSRIs, suggesting a specific relationship between the circular RNA and SSRIs as a whole. This blood test could help doctors choose the right medication on the first try, reducing the burden on patients and the healthcare system.",
  "summary": "A new study identifies a stable, brain-derived RNA molecule in the bloodstream that accurately predicts whether a patient will respond to common SSRI antidepressants, potentially saving months of trial-and-error treatments.",
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}