Trial reportPsychopharmacology2015
D-serine plasma concentration is a potential biomarker of (R,S)-ketamine antidepressant response in subjects with treatment-resistant depression.
Trial report in Psychopharmacology, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 38 papers, 5 of them syntheses that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
38 citing papers in PubMed, 5 syntheses or guidelines pooled it, 82 citations in OpenAlex.
- Ketamine-induced altered states of consciousness: a systematic review of implications for therapeutic outcomes in psychiatric practices.European archives of psychiatry and clinical neuroscience · 2025Pooled it
- Brain-based correlates of antidepressant response to ketamine: a comprehensive systematic review of neuroimaging studies.The lancet. Psychiatry · 2023Pooled it
- Efficacy and safety of perioperative application of ketamine on postoperative depression: A meta-analysis of randomized controlled studies.Molecular psychiatry · 2023Pooled it
- Blood-based biomarkers of antidepressant response to ketamine and esketamine: A systematic review and meta-analysis.Molecular psychiatry · 2022Pooled it
- Pooled it
- d-Serine is a potential biomarker for clinical response in treatment of post-traumatic stress disorder using (R,S)-ketamine infusion and TIMBER psychotherapy: A pilot study.Biochimica et biophysica acta. Proteins and proteomics · 2018Trial
- Sympathetic activation but not dissociation linked to ketamine's sustained antidepressant effect.Therapeutic advances in psychopharmacology · 2026Article
- Detection and functional assessment of D-amino acids as potential biomarkers in neurological disorders.Molecular biology reports · 2025Review
- Energy metabolism inmBio · 2025Review
- SLC1A4 and Serine Homeostasis: Implications for Neurodevelopmental and Neurodegenerative Disorders.International journal of molecular sciences · 2025Review
- Detection and analysis of chiral molecules as disease biomarkers.Nature reviews. Chemistry · 2023Review
- Prognostic Significance of Blood-Based Baseline Biomarkers in Treatment-Resistant Depression: A Literature Review of Available Studies on Treatment Response.Brain sciences · 2022Review
- Review
- A Bibliometric Analysis of Research on Ketamine From 2001 to 2020.Frontiers in molecular neuroscience · 2022Article
- Enantioselectivity Effects in Clinical Metabolomics and Lipidomics.Molecules (Basel, Switzerland) · 2021Review
- Time to re-engage psychiatric drug discovery by strengthening confidence in preclinical psychopharmacology.Psychopharmacology · 2021Review
- Evaluation of Analytes Characterized with Potential Protective Action after Rat Exposure to Lead.Molecules (Basel, Switzerland) · 2021Article
- Advances in D-Amino Acids in Neurological Research.International journal of molecular sciences · 2020Review
- Ketamine as an antidepressant: overview of its mechanisms of action and potential predictive biomarkers.Therapeutic advances in psychopharmacology · 2020Article
- Glycine Signaling in the Framework of Dopamine-Glutamate Interaction and Postsynaptic Density. Implications for Treatment-Resistant Schizophrenia.Frontiers in psychiatry · 2020Review
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
14 authors at 5 institutions in 2 countries.
Funding
Abstract
rationale(R,S)-ketamine is a rapid and effective antidepressant drug that produces a response in two thirds of patients with treatment-resistant depression (TRD). The underlying biochemical differences between a (R,S)-ketamine responder (KET-R) and non-responder (KET-NR) have not been definitively identified but may involve serine metabolism.
objectivesThe aim of the study was to examine the relationship between baseline plasma concentrations of D-serine and its precursor L-serine and antidepressant response to (R,S)-ketamine in TRD patients.
methodsPlasma samples were obtained from 21 TRD patients at baseline, 60 min before initiation of the (R,S)-ketamine infusion. Patients were classified as KET-Rs (n = 8) or KET-NRs (n = 13) based upon the difference in Montgomery-Åsberg Depression Rating Scale (MADRS) scores at baseline and 230 min after infusion, with response defined as a ≥50 % decrease in MADRS score. The plasma concentrations of D-serine and L-serine were determined using liquid chromatography-mass spectrometry.
resultsBaseline D-serine plasma concentrations were significantly lower in KET-Rs (3.02 ± 0.21 μM) than in KET-NRs (4.68 ± 0.81 μM), p < 0.001. A significant relationship between baseline D-serine plasma concentrations and percent change in MADRS at 230 min was determined using a Pearson correlation, r = 0.77, p < 0.001, with baseline D-serine explaining 60 % of the variance in (R,S)-ketamine response. The baseline concentrations of L-serine (L-Ser) in KET-Rs were also significantly lower than those measured in KET-NRs (66.2 ± 9.6 μM vs 242.9 ± 5.6 μM, respectively; p < 0.0001).
conclusionsThe results demonstrate that the baseline D-serine plasma concentrations were significantly lower in KET-Rs than in KET-NRs and suggest that this variable can be used to predict an antidepressant response following (R,S)-ketamine administration.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.