ClinicalTrials.gov record NCT07858175

Clinical Evaluation of a Novel DAB Chromogenic Tissue-Based Assay for Detecting Anti-GABABR Antibodies

Record copied from ClinicalTrials.gov: Oct 10, 2026AI summaries generated: Oct 10, 2026

Anti-GABAB Receptor Encephalitis: Evaluation of Autoantibodies by a Novel DAB Chromogenic Tissue-Based Assay - A Multicenter, Blinded, Cross-Sectional Study

StatusNot yet recruitingThe study has been registered but has not started enrolling. Sites and contacts may not be listed yet.
Study typeObservationalA study in which researchers do not assign participants to a treatment or other intervention. They observe or measure what happens, which may include study visits, tests, questionnaires or a review of medical records.
Age14 years old to 85 years old
SexAll
LocationChina
AI summaryWhat this study is about, in plain languageShow ▾Hide ▴

AI-written from the registry record, not the study's own wording. May contain errors or omissions. Check the registry text on this page and the original record ↗ before acting on it.

This multicenter, blinded, cross-sectional observational study evaluates a novel DAB chromogenic tissue-based assay (DAB-TBA) for detecting anti-GABABR antibodies. About 300 residual serum and cerebrospinal fluid samples are included across four groups: anti-GABABR antibody-positive encephalitis (n=50), suspected autoimmune encephalitis with negative cell-based assay (n=100), Alzheimer's disease (n=50), and anti-NMDAR antibody-positive encephalitis (n=100). Samples are tested blinded; discordant results will be reviewed by an independent panel and accuracy measures (sensitivity, specificity, ROC/AUC) will be calculated.

What it is studying. The study tests how well the DAB chromogenic tissue-based assay detects anti-GABABR antibodies compared with the reference cell-based assay (CBA). It will measure accuracy (sensitivity, specificity, ROC/AUC), report agreement between serum and CSF results, and assess inter-reader concordance. Discordant cases will be adjudicated using confirmatory methods and clinical follow-up.

What the researchers hope to learn. Validate the clinical performance of the novel DAB chromogenic TBA for anti-GABABR antibody detection; determine sensitivity, specificity, and AUC versus the CBA reference; quantify concordance (Cohen's kappa) between DAB-TBA and CBA and between serum and CSF; assess subgroup performance and inter-reader agreement; adjudicate discordant results with confirmatory testing and clinical follow-up.

What this study is about

The study's own summary, as published on ClinicalTrials.gov. Underlined terms have a short explanation.

This multicenter, blinded, cross-sectional study aims to evaluate the clinical performance of a novel DAB chromogenic tissue-based assay (TBA) for detecting anti-GABAB receptor (anti-GABABR) antibodies. A total of 300 participants will be enrolled across four groups: (a) 50 patients with anti-GABABR antibody-positive encephalitis; (b) 100 patients with suspected autoimmune encephalitis and negative anti-neuronal antibody cell-based assay (CBA); (c) 50 patients with non-autoimmune disease (Alzheimer's disease); and (d) 100 patients with anti-NMDAR antibody-positive encephalitis. Residual serum and cerebrospinal fluid samples will be tested using the optimized DAB-TBA. Discordant results between CBA and DAB-TBA will be adjudicated by an independent panel using confirmatory methods (immunoblot, repeat CBA, and clinical follow-up), and inter-reader agreement will be reported. The sensitivity, specificity, and ROC curve of the assay will be evaluated against the reference standard.

Eligibility

The criteria exactly as listed on ClinicalTrials.gov. Only the study team can say whether they apply to you.

Inclusion criteria

  • Group a: age 14-85 years; anti-GABABR antibody CBA positive; diagnosed with GABABR antibody encephalitis. Group b: age 14-85 years; suspected autoimmune encephalitis with acute/subacute onset (<3 months) and one or more neurological/psychiatric symptoms (e.g. memory impairment, seizures, psychiatric/behavioral abnormalities); anti-neuronal antibody CBA negative; other etiologies reasonably excluded; identifiable address and resident in the region during treatment; willing to provide informed consent and comply with follow-up. Group c: age 14-85 years; non-autoimmune disease patients (Alzheimer's disease confirmed by serum/CSF AD biomarker testing). Group d: age 14-85 years; anti-NMDAR antibody CBA positive; diagnosed with NMDAR antibody encephalitis.

Exclusion criteria

  • Residual serum or CSF volume insufficient for DAB-TBA and confirmatory testing.
  • Sample quality unacceptable (gross hemolysis, lipemia, contamination, or clot).
  • Freeze-thaw cycles exceeding the predefined limit (specify N).
  • Key clinical information (final diagnosis, CBA result, or demographic data) unavailable or incomplete.
  • Sample previously included in this study (repeat sample from the same patient).

Study description and what participation involves

The study's detailed description, as published on ClinicalTrials.gov.

Detailed description from the registry

Anti-GABAB receptor (anti-GABABR) encephalitis is a recognized subtype of autoimmune encephalitis. Antibody detection is essential for diagnosis and differential diagnosis, and cell-based assays (CBA) are the current recommended reference method. The tissue-based assay (TBA) using DAB chromogenic immunohistochemistry offers a widely accessible complement for detecting anti-neuronal antibodies. This study validates the clinical performance of a novel DAB chromogenic TBA developed by Guangzhou KingMed Diagnostics Center. Participants are recruited from neurology departments across multiple centers and enrolled into four groups based on clinical diagnosis and CBA results. Residual serum and CSF samples (no additional sampling) are tested in a blinded manner, and the sensitivity, specificity, and ROC curve of the DAB-TBA for detecting anti-GABABR antibodies are evaluated against the reference standard.

AI summaryWhat participation may involve, in plain languageShow ▾Hide ▴

AI-written from the registry record, not the study's own wording. May contain errors or omissions. Check the registry text on this page and the original record ↗ before acting on it.

The study uses existing (residual) serum and cerebrospinal fluid (CSF) samples from enrolled patients; it does not perform additional sampling. Residual samples will be tested in a blinded fashion with the novel DAB chromogenic tissue-based assay (DAB-TBA) and compared to prior cell-based assay (CBA) results. If DAB-TBA and CBA results disagree, an independent panel may use confirmatory methods (immunoblot, repeat CBA) and clinical follow-up to resolve the discrepancy. To take part, your residual sample must have sufficient volume and acceptable quality; samples with gross hemolysis, lipemia, contamination, clotting, or too many freeze–thaw cycles (the record does not state the allowed number) will be excluded, and key clinical information (final diagnosis, CBA result, or demographic data) must be available.

How the study is structured. Observational, multicenter, blinded, cross-sectional (case-only) study. Participants are placed into four predefined groups; no additional sampling is performed — the study uses residual serum and cerebrospinal fluid samples. All samples are tested in a blinded manner with comparison to CBA results; discordant findings are adjudicated by an independent panel using confirmatory tests and follow-up.

Questions you could ask

These questions are suggestions for a conversation with the study team or your own clinician, not advice.

  • This is an observational study, so the study itself gives no treatment. What would taking part involve for me, and would it change my usual care?
  • The registry says recruitment has not started. When is it expected to open, and can I register interest now?
  • The listed sites are in China. Is any of them reachable for me, and does the study help with travel?
  • Which of the eligibility criteria would need to be checked with tests before I could join?

More on autoimmune encephalitis

Clinical trials40 trials listed for autoimmune encephalitisEvery trial the registry lists for autoimmune encephalitis, with recruitment status, phase and sites, updated from ClinicalTrials.gov.See all trials →Research updatesWhat changed in autoimmune encephalitis researchLatest monthly update: September 2026. Includes: Efgartigimod reports. New research summarized each month in plain language, with links to every source paper.Read the latest update →

Important dates

Study start
October 2026 (estimated)
Primary completion
October 2028 (estimated)
Study completion
October 2028 (estimated)
Target enrollment
300 participants (estimated)
Last updated on registry
Oct 5, 2026
Data verified
Oct 10, 2026

Sponsor and research team

The lead sponsor funds and oversees the trial. A pharmaceutical or biotech company sponsor typically means the study is testing that company's drug or device; a hospital, university, or government agency usually indicates investigator-initiated or publicly funded research.

Lead sponsor
Third Affiliated Hospital, Sun Yat-Sen University
Principal investigator
Wei Qiu, Chief Physician
Third Affiliated Hospital, Sun Yat-Sen University
Collaborators
  • Guangzhou KingMed Center for Clinical Lab.Co., Ltd

Central study contact

If you're interested in participating, the central contact can answer general questions about the study — including eligibility requirements and how to find a recruiting site near you. Actual eligibility is determined by the site's medical team.

Participating sites (5)

Terms used on this page · explanations by MedicalUpdates.ai

blinded
Who does not know which intervention a participant is receiving. It can apply to participants, the people giving the treatment, those assessing results, or those analysing the data.
follow-up
The period after treatment or enrolment during which participants are observed or contacted, for example to record side effects or outcomes.
informed consent
The process of explaining a study, including its risks and what participation involves, so that a person can decide freely whether to take part. Consent is usually documented in writing, and a participant can choose to leave the study later.
biomarker
Something measurable in the body, such as a blood test result or an imaging finding, that indicates how a condition or treatment is behaving.
Inclusion Criteria
The conditions a person must meet to be considered for the study, for example a confirmed diagnosis, an age range or a test result.
Exclusion Criteria
The conditions that rule a person out even if they meet the inclusion criteria, for example other illnesses, certain medicines or pregnancy.

The study record on this page is reproduced from ClinicalTrials.gov, a database of the U.S. National Library of Medicine, where it was submitted by the study sponsor. MedicalUpdates.ai does not own this content, is not affiliated with or endorsed by ClinicalTrials.gov, NIH, or the U.S. Government, and does not verify the record. Plain-language notes, the glossary and the questions above are added by this site; text in the boxes marked "AI summary" was written by an AI model and may contain errors. Registry records change over time. Check the original record for the current version and discuss eligibility or participation with a qualified healthcare professional.

← Back to clinical trials