At a glance
- What the study gets you
- Access to the study treatment being tested
- Type of study
- Interventional (receives a drug or procedure)
- Time in hospital
- In-person visits at study sites — visit count not specified by the sponsor
- Drug or intervention
- GM-2505 (drug)
- How long the study runs
- Study runs about 30 months (dates as stated)
- About the drug or intervention
- GM-2505 — drug: IV
- Patient visit burden
- Not specified by the sponsor
- Type of study
- Testing a treatment
- Ages
- 18 Years to 65 Years
- Who
- All
- Number of participants
- 126
- Started
- 2024-01-31
- Last checked
- 2026-09
Plain English Summary
What is this study?
- • Testing a new treatment for major depressive disorder
- • Phase2 - 126 participants
- • This is a three-part Phase 2a study
Who can take part?
- • Ages 18 Years to 65 Years
- • Diagnosed with major depressive disorder
Where?
- • Manchester - MAC Clinical Research
This is a simplified summary. Always discuss with your doctor before making any decisions.
About This Trial
This is a three-part Phase 2a study. The aim of Part A is to assess the safety and tolerability and preliminary antidepressant efficacy in patients with MDD who are not currently on an antidepressant therapy. The aim of Part B is to assess the antidepressant efficacy, safety and tolerability in patients with MDD who are partial responders while on a current and adequate single SSRI or SNRI treatment. Part C aims to replicate the monotherapy findings of Part A, but with a lower control group dose.
Major Depressive Disorder
How this trial compares with your answers
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What we know so far
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Preliminary match based on your answers. Full eligibility requires on-site assessment including medical history, physical exam, and lab tests. This does not guarantee enrolment.
Eligibility at a Glance
Key info
- Age: 18 Years - 65 Years
- Who can join: All genders
What the study is looking for
- ✓Patients are male or female, of any ethnic origin.
- ✓Patients are aged between 18 to 65 years, inclusive.
- ✓Current moderate to severe MDD diagnosis confirmed with a MADRS-SIGMA
- ✓Concomitant depression therapy:
- ✓(Part B) Patients need to be on stable treatment with any SSRI or SNRI for at least 6 weeks prior to screening and...
Who cannot take part
- ✗In first degree relatives, a history of schizophrenia, psychosis, bipolar disorder, delusional disorder, paranoid...
- ✗Current or prior (six weeks before Screening) use of any SSRI/SNRI medication (Part A only).
See the full criteria
Key Inclusion Criteria:
1. Patients are male or female, of any ethnic origin.
2. Patients are aged between 18 to 65 years, inclusive.
3. Patients meet the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) diagnostic criteria for recurrent MDD without psychotic features, as assessed with the Mini-International Neuropsychiatric Interview (MINI) at Screening.
4. Current moderate to severe MDD diagnosis confirmed with a MADRS-SIGMA
5. Concomitant depression therapy:
1. (Part A) Patients need to be stable and must not have taken any SSRI or SNRI for at least 6 weeks prior to Screening and must be willing to avoid starting a new pharmacological treatment for MDD until the end of the study procedures and assessments. Discontinuing current treatment is not allowed if done for the purposes of achieving eligibility for this study.
2. (Part B) Patients need to be on stable treatment with any SSRI or SNRI for at least 6 weeks prior to screening and must be willing to remain on the SSRI or SNRI for the duration of the trial
3. Patients receiving any form of psychotherapy or counselling must have been receiving therapy at Screening and must be willing to remain in therapy until the end of the study procedures and assessments.
Key Exclusion Criteria:
1. Patient has current or past primary DSM-5 diagnosis of a psychotic disorder or MDD with psychotic features, bipolar, or related disorders. A current diagnosis of PTSD, complex PTSD and borderline personality disorder are exclusionary. Other psychiatric disorders besides MDD should not be the primary disorder.
2. In first degree relatives, a history of schizophrenia, psychosis, bipolar disorder, delusional disorder, paranoid personality disorder or schizoaffective disorder.
3. Current or prior (six weeks before Screening) use of any SSRI/SNRI medication (Part A only).
4. Current or prior (five weeks before Screening) use of any monoamine oxidase inhibitor (\[MAO-I\]; including phenelzine, tranylcypromine, isocarboxazid, iproniazid, selegiline, rasagiline, the reversible MAO-I moclobemide and the antibiotic linezolid).or any tricyclic antidepressant
Where Is This Study? (1 UK site)
MAC Clinical Research
Manchester, United Kingdom
Data sourced from ClinicalTrials.gov · Last verified: 2026-09