An Open-Label Extension Study to Evaluate the Safety and Tolerability of SPT-300 (GlyphAllo) in Participants With Major Depressive Disorder, With or Without Anxious Distress (BUOY-1 OLE Study)
A 6-Week, Multicenter, Open-Label, Monotherapy, Extension Study of SPT-300 in Adults With Major Depressive Disorder, With or Without Anxious Distress
2 other identifiers
interventional
360
6 countries
29
Brief Summary
This is an open-label, monotherapy, extension study to evaluate the safety and tolerability of SPT-300 (GlyphAllo) in adults with major depressive disorder (MDD), with or without anxious distress.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for phase_2
Started Sep 2025
29 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
September 2, 2025
CompletedStudy Start
First participant enrolled
September 2, 2025
CompletedFirst Posted
Study publicly available on registry
September 9, 2025
CompletedPrimary Completion
Last participant's last visit for primary outcome
May 1, 2027
ExpectedStudy Completion
Last participant's last visit for all outcomes
May 1, 2027
March 24, 2026
March 1, 2026
1.7 years
September 2, 2025
March 20, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (1)
Safety and tolerability assessments based on Treatment-emergent Adverse Events (TEAEs), Serious Adverse Events (SAEs) and validated clinical scales and procedures
Adverse events (AEs) are monitored from Day 1 to 49. A TEAE is as any AE with an onset after first dose of study treatment up to Day 49. Clinically significant abnormalities in clinical laboratory evaluations, ECGs, vital signs, physical examinations and Columbia Suicide Severity Rating Scale (C-SSRS) will be reported as TEAEs.
Up to Day 49
Study Arms (1)
SPT-300
EXPERIMENTALParticipants will receive SPT-300 capsules once daily for 42 days
Interventions
A prodrug of allopregnanolone, a small molecule drug
Eligibility Criteria
You may qualify if:
- Participant who completed treatment in Study SPT-300-2024-203 (i.e., participant who competed Visit 8 \[Day 42\] of Study SPT-300-2024-203 \[BUOY-1 Study\]).
- Women of childbearing potential (WOCP) must not plan to become pregnant during the course of the study or be currently breastfeeding. WOCP must agree to use a highly effective form of contraception during participation in the study and for 30 days after receiving the last dose of study treatment.
- Participant is willing and able to refrain from the use of drugs of abuse.
You may not qualify if:
- Participants who, in the opinion of the Investigator, medical monitor, or Sponsor, should not participate in the study.
- Participants who, in the judgment of the Investigator, were noncompliant with trial procedures or with study treatment administration during the double-blind study (BUOY-1 Study).
- Female participants with a positive urine pregnancy test result. Female participants may be enrolled without a negative urine test if they are surgically sterile or at least 2 years post-menopause.
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- Seaport Therapeuticslead
- Premier Researchcollaborator
Study Sites (29)
Seaport Investigator Site
Chino, California, 91710, United States
Seaport Investigator Site
Garden Grove, California, 92845-2506, United States
Seaport Investigator Site
Glendale, California, 91206, United States
Seaport Investigator Site
West Palm Beach, Florida, 33407, United States
Seaport Investigator Site
Atlanta, Georgia, 30328, United States
Seaport Investigator Site
Decatur, Georgia, 30030, United States
Seaport Investigator Site
Boston, Massachusetts, 02116, United States
Seaport Investigator Site
St Louis, Missouri, 63141, United States
Seaport Investigator Site
Brooklyn, New York, 11235, United States
Seaport Investigator Site
New York, New York, 10029, United States
Seaport Investigator Site
Staten Island, New York, 10314, United States
Seaport Investigator Site
North Canton, Ohio, 44720, United States
Seaport Investigator Site
Irving, Texas, 75062, United States
Seaport Investigator Site
Plovdiv, 4004, Bulgaria
Seaport Investigator Site
Sofia, 1000, Bulgaria
Seaport Investigator Site
Brno, 602 00, Czechia
Seaport Investigator Site
Prague, 100 00, Czechia
Seaport Investigator Site
Prague, 186 00, Czechia
Seaport Investigator Site
Schwerin, Mecklenburg-Vorpommern, 19053, Germany
Seaport Investigator Site
Chemnitz, 09111, Germany
Seaport Investigator Site
Bialystok, 15-404, Poland
Seaport Investigator Site
Bialystok, 15-464, Poland
Seaport Investigator Site
Bydgoszcz, 85-080, Poland
Seaport Investigator Site
Gdansk, 80-438, Poland
Seaport Investigator Site
Leszno, 64-100, Poland
Seaport Investigator Site
Poznan, 60-744, Poland
Seaport Investigator Site
Tuszyn, 95-080, Poland
Seaport Investigator Site
Rimavská Sobota, 979 01, Slovakia
Seaport Investigator Site
Vranov nad Topľou, 09301, Slovakia
MeSH Terms
Conditions
Condition Hierarchy (Ancestors)
Study Officials
- PRINCIPAL INVESTIGATOR
David Walling, Ph.D.
Collaborative Neuroscience Research - Garden Grove
Study Design
- Study Type
- interventional
- Phase
- phase 2
- Allocation
- NA
- Masking
- NONE
- Purpose
- TREATMENT
- Intervention Model
- SINGLE GROUP
- Sponsor Type
- INDUSTRY
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
September 2, 2025
First Posted
September 9, 2025
Study Start
September 2, 2025
Primary Completion (Estimated)
May 1, 2027
Study Completion (Estimated)
May 1, 2027
Last Updated
March 24, 2026
Record last verified: 2026-03