🏛️ Verified NIH Record • Updated 2026-07-30
Zelquistinel or Placebo for the Reduction of Symptoms of Major Depressive Disorder (NCT06547489)
🟢 Recruiting Phase2 💊 Investigational Drug / Biologic Sponsor: Syndeio Biosciences, Inc
🩺 Plain-English Summary (8th-Grade Level)
The goal of this clinical trial is to learn if zelquistinel works to treat depression in adults. It will also learn about the safety of zelquistinel. The main questions it aims to answer are: Does zelquistinel reduce depression scores in participants compared to participants who take a placebo (a look-alike tablet that contains no zelquistinel)? What medical problems are observed in participants who take zelquistinel? Participants will take one tablet of zelquistinel or placebo every week for 6 weeks. Participants will visit the clinic every week of the 6 week period to have the severity of their depression evaluated.
Who can join: To join this study, participants generally need to meet the listed inclusion criteria (18 items) and avoid the listed exclusions (35 items).
Location: University of Alabama at Birmingham — Birmingham, Alabama
📋 "Do I Qualify?" — 1-Minute Self Screener
Instant ChecklistCheck every box below. If you can check all of them, you may meet the study's basic screening requirements (final eligibility is confirmed by the site team).
Usually NOT eligible if any of the following apply:
- Exclusion Criteria: Any subject who meets any of the following criteria will be excluded from study participation:
- Evidence of treatment-resistant MDD, defined by having an inadequate response (≤25%) to 2 or more different medications approved for the treatment of MDD at an adequate dose (per locally approved label) for an adequate duration during the current episode using the Massachusetts General Hospital Antidepressant Treatment Rating Questionnaire (ATRQ).
- Current DSM-5 diagnosis of bipolar (or related disorders), antisocial personality disorder, obsessive compulsive disorder, borderline personality disorder, post-traumatic stress disorder, panic disorder, or attention-deficit/hyperactivity disorder. Subjects not meeting full DSM 5 criteria for borderline personality disorder but exhibiting recurrent suicidal gestures, threats, or self-mutilating behaviors should also be excluded.
- Subject has a current or prior DSM-5 diagnosis of a psychotic disorder, or MDD with psychotic features.
- Current concomitant treatment with Food and Drug Administration (FDA)-approved antidepressants, antipsychotics, mood stabilizers, sedatives, or stimulants. Current or past treatment with esketamine, ketamine, or psychedelics is prohibited. Subject must have current concomitant treatment discontinued at least 14 days prior to the Baseline Visit (V2). Subjects may continue anxiolytic agents, except for drugs that are also used to treat depression, or benzodiazepines, or sleep aids \[see Section 5.5.1 for a nonexhaustive list\] (except trazodone) so long as they have been on a stable dose for at least 3 months and do not intend to change dose during double-blind treatment period (Day 1, Week 1 through end of Week 6 \[Day 43\]). Subjects who use cannabis or cannabis-derived molecules, including tetrahydrocannabinol (THC), whether natural or chemically-synthesized, hemp seed oil, or cannabidiol (CBD) products (eg, gummies), must be discontinued for at least 14 days prior to the Baseline Visit (V2).
- Treatment with any experimental antidepressant agent or treatment with a psychedelic agent in an FDA-approved clinical study within the past 12 months.
- History of electroconvulsive therapy, vagus nerve stimulation, deep brain stimulation, or repetitive transcranial magnetic stimulation within the past 5 years or has had a failure of response to electroconvulsive therapy at any time.
- Subject has clinically significant renal dysfunction as assessed by the estimated glomerular filtration rate \<70 mL/min using the Chronic Kidney Disease Epidemiology Collaboration - creatinine (CKD-EPI creatinine) methodology.
- Subject has liver protein and enzyme (alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, total bilirubin, lactate dehydrogenase test result \>1.5 times the upper limit of normal (subjects with a diagnosis of Gilbert's Syndrome may be eligible if no liver function or enzyme test results other than total bilirubin are \>1.5 times upper limit of normal).
- Subject has resting pulse rate (supine) \<50 or \>100 bpm at the Screening Visit (V1) or predose Baseline (V2).
- Subject has resting diastolic blood pressure \<50 mmHg at the Screening Visit (V1) or predose Baseline (V2).
- Subject has cardiac PR interval \>250 msec at the Screening Visit (V1) or predose Baseline (V2), or QTcF or QTcB interval \>450 msec in males or \>470 msec in females, or QRS interval \>120 msec.
🔍 Extracted verbatim from the official NIH eligibility criteria. Always confirm with the study coordinator.
📍 All Participating Trial Locations (34 Sites)
- University of Alabama at Birmingham — Birmingham, Alabama
- University of Alabama at Birmingham-Huntsville — Huntsville, Alabama
- Wr-Pri, Llc — Encino, California
- Irvine Clinical Research — Irvine, California
- CalNeuro Research Group — Los Angeles, California
- Pacific Clinical Research Management Group LLC — Upland, California
- Sunwise Clinical Research LLC — Walnut Creek, California
- MCB Clinical Research Centers, Inc. — Colorado Springs, Colorado
- Mountain View Clinical Research — Denver, Colorado
- University of Connecticut School of Medicine Psychiatry Department — Farmington, Connecticut
- Clinical Neuroscience Solutions, Inc. — Jacksonville, Florida
- D&H Pompano Research Center, LLC — Margate, Florida
- Premier Clinical Research Institute, Inc. — Miami, Florida
- Miami Dade Medical Research Institute — Miami, Florida
- Clinical Neuroscience Solutions, Inc. — Orlando, Florida
- CenExel iRS (iResearch Savannah) — Savannah, Georgia
- Revive Research Institute — Elgin, Illinois
- KUMC-Wichita — Wichita, Kansas
- Quantum Research Associates Corp. — Louisville, Kentucky
- Boston Clinical Trials — Boston, Massachusetts
- Mayflower Clinical — Russells Mills, Massachusetts
- Vector Clinical Trials — Las Vegas, Nevada
- Neurobehavioral Research, Inc. — Cedarhurst, New York
- Insight Clinical Trials LLC — Independence, Ohio
- Sooner Clinical Research, Inc. — Oklahoma City, Oklahoma
💰 Cost, Insurance & Patient Rights
- 100% Free Items: The investigational treatment and protocol-required procedures are supplied at zero cost by the sponsor.
- Routine Patient Care: Under federal law (ACA § 2709) and many state statutes, routine care costs are covered during participation.
- Voluntary Participation: You may withdraw at any time without affecting your standard medical care.