ACP-211 alone for adults whose depression hasn't improved with antidepressants

A Double-Blind, Placebo-Controlled, Parallel Group, Efficacy and Safety Study of ACP-211 Monotherapy in Adults With Major Depressive Disorder and Inadequate Response to Antidepressant Treatment

This trial tests whether ACP-211 can help adults with major depressive disorder who haven't improved on antidepressants do better than a placebo.

Quick facts

• Phase: PHASE2
• Study type: Interventional
• Enrollment: 153 (estimated)
• Ages: 18 Years to 65 Years
• Sex: All
• Sponsor: ACADIA Pharmaceuticals Inc. (industry)
• Locations: 16 sites (Birmingham, Alabama and 15 other locations)
• Trial ID: NCT07284667 on ClinicalTrials.gov

What this trial studies

This is a Phase 2, randomized, double-blind trial comparing ACP-211 monotherapy to placebo in adults aged 18–65 with major depressive disorder who have not responded adequately to at least two antidepressants. Eligible participants must be on a stable approved antidepressant dose and have moderate-to-severe symptoms at screening (MADRS ≥28, CGI-S ≥4, QIDS-SR16 ≥16). The study will measure changes in depressive symptom scores over the treatment period and closely monitor adverse events. Results will compare symptom improvement and safety between the ACP-211 and placebo groups.

Who should consider this trial

Good fit: Adults 18–65 with major depressive disorder who have had an inadequate response to at least two antidepressants, are on a stable antidepressant dose, and meet the study symptom-score thresholds are ideal candidates.

Not a fit: People with bipolar disorder, psychotic disorders, recent substance use disorders, active high suicidal risk, certain personality disorders, pregnant women, or those outside the 18–65 age range are unlikely to qualify or benefit from this protocol.

Why it matters

Potential benefit: If successful, ACP-211 could offer a new monotherapy option to reduce depressive symptoms in adults who do not respond to current antidepressants.

How similar studies have performed: Some other novel therapies for treatment-resistant depression (for example, intranasal esketamine) have shown benefit for some patients, but ACP-211 is a different investigational medicine and its effectiveness is not yet proven.

Eligibility criteria

Inclusion Criteria:

* Adults ≥18 and ≤65 years of age
* Provides written informed consent
* Clinical diagnosis of MDD
* History of inadequate response to at least two antidepressants, with at least one inadequate response documented during the current episode
* Currently treated with an approved antidepressant at a stable dose prior to Screening
* MADRS total score ≥28, CGI-S score ≥4 , and QIDS-SR16 score ≥16 at Screening and Baseline
* Females of childbearing potential must have a negative pregnancy test and agree to use acceptable contraception; males must agree to use barrier protection and refrain from sperm donation

Exclusion Criteria:

* Current diagnosis of certain personality disorders or persistent depressive disorder
* Recent substance use disorders, excluding caffeine or nicotine
* Active suicidal risk or recent suicidal attempt
* History of schizophrenia, psychotic disorders, bipolar disorder, or MDD with psychotic features
* Current treatment requirement for PTSD, acute stress disorder, panic disorder, or OCD
* History of neuroleptic malignant syndrome, serotonin syndrome, or epilepsy (except single febrile seizure in infancy)
* Documented non-response to ADT, including ketamine or esketamine
* Allergy or sensitivity to ketamine or esketamine
* Significant cardiovascular disease
* Positive history of hepatitis B, hepatitis C, or HIV infection
* Unstable diabetes or uncontrolled medical conditions
* Positive urine drug test for an illicit drug or cannabis
* Received neuromodulation therapies (ECT,TMS, VNS, DBS) in the current depressive episode
* Recent initiation or change in psychotherapy Additional inclusion/exclusion criteria apply. Participants will be evaluated at Screening to ensure that all criteria for study participation are met.

Where this trial is running

Birmingham, Alabama and 15 other locations

• University of Alabama at Birmingham — Birmingham, Alabama, United States (RECRUITING)
• Inland Psychiatric Medical Group — Chino, California, United States (RECRUITING)
• PNS Clinical Research LLC dba ATP Clinical Research — Orange, California, United States (RECRUITING)
• Mountain View Clinical Research — Denver, Colorado, United States (RECRUITING)
• The Medici Medical Research — Hollywood, Florida, United States (RECRUITING)
• Sandhill Research, LLC/DBA Accel Research Sites — Largo, Florida, United States (RECRUITING)
• Clinical Neuroscience Solutions, Inc. — Orlando, Florida, United States (RECRUITING)
• IPTB Clinical Research — Tampa, Florida, United States (RECRUITING)
• Neuroscience Research Institute, Inc. — West Palm Beach, Florida, United States (RECRUITING)
• Vitalix Clinical, Inc. — Worcester, Massachusetts, United States (RECRUITING)
• Redbird Research LLC — Las Vegas, Nevada, United States (RECRUITING)
• CenExel Hassman Research Institute, LLC — Marlton, New Jersey, United States (RECRUITING)
• Integrative Clinical Trials LLC — Brooklyn, New York, United States (RECRUITING)
• Neuro-Behavioral Clinical Research — North Canton, Ohio, United States (RECRUITING)
• Dynamed Clinical Research LP d/b/a DM Clinical Research — Houston, Texas, United States (RECRUITING)
• Olympus Clinical Research, LLC — Katy, Texas, United States (RECRUITING)

Study contacts

• Study coordinator: Sandy Filosi

Conditions: Major Depressive Disorder, Depressive Disorder, Treatment-Resistant, Antidepressive Agents, Randomized Controlled Trial, Double-Blind Method, Clinical Trial, Phase II, Psychiatric Status Rating Scales, Ketamine