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A Study of the Efficacy and Safety of SP-624 in the Treatment of Adults With Major Depressive Disorder

A Multi-center, Double-Blind, Randomized, Placebo-Controlled Study of the Efficacy and Safety of SP-624 in the Treatment of Adults With Major Depressive Disorder

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT06254612
Enrollment
497
Registered
2024-02-12
Start date
2024-03-25
Completion date
2026-07-08
Last updated
2026-08-18

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Major Depressive Disorder

Brief summary

This is a Phase 2B clinical study evaluating the effectiveness and safety of SP-624 as compared to placebo in the treatment of adults with Major Depressive Disorder.

Interventions

DRUGSP-624

Once daily oral administration of two capsules totaling 20 mg/day

DRUGPlacebo

Once daily oral administration of two matching placebo capsules

Sponsors

Sirtsei Pharmaceuticals, Inc.
Lead SponsorINDUSTRY
Rho, Inc.
CollaboratorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No

Inclusion criteria

Key Inclusion Criteria: * Males and females, aged 18 to 65 years, inclusive. * Meet DSM-5 criteria for moderate to severe MDD, as confirmed by the Mini International Neuropsychiatric Interview (MINI). * In generally good physical health, in the opinion of the Investigator. * Body mass index (BMI) must be ≥ 18 and ≤ 45 kg/m2. Key

Exclusion criteria

* Female who is pregnant, breastfeeding, or less than 6 months postpartum at screen. * A history of or current DSM-5 diagnosis of MDD with psychotic features, any schizophrenia spectrum and other psychotic disorders, bipolar disorder, or personality disorder. * Presence or history of any known clinically significant cardiovascular disorders including, but not limited to: coronary artery disease, heart failure, valvular heart disease, cardiomyopathies, myocardial infarction, chamber enlargement or hypertrophy, or orthostatic hypotension. * Presence of uncontrolled hypertension, defined as consistent sitting systolic blood pressure (SBP) \>160 mmHg or consistent sitting diastolic blood pressure (DBP) \>95 mmHg despite present therapy. * Screening laboratory value(s) outside the laboratory reference range that are considered to be clinically significant by the Investigator (clinical chemistry, hematology, thyroid function, and urinalysis).

Design outcomes

Primary

MeasureTime frameDescription
Change from Baseline in the Montgomery-Asberg Depression Rating Scale (MADRS) total score.Baseline to Week 4The MADRS is a 10-item depression rating scale used to assess the severity of depression. Individual items are scored on a 7-point scale (0 to 6). The toal score is the sum of individual items, ranging from 0 to 60; where a higher score indicates more depression.

Secondary

MeasureTime frameDescription
Change from Baseline in the Clinical Global Impression - Severity (CGI-S) score.Baseline to Weeks 1-4 and 1- and 2- Week Follow-upThe CGI-S is a 7-point scale to rate the severity of the participant's illness at the time of assessment, relative to the clinician's past experience with participants who have the same diagnosis. A score of 1 represents "normal" and 7 represents "most extremely ill".
Change from Baseline in Quick Inventory of Depressive Symptomology-Self-Report (QIDS-SR) total score.Baseline to Weeks 1-4 and 1- and 2- Week Follow-upThe QIDS-SR is a 16-item self-reported scale where each item has a 4-point scale where 0 represents least impact scores while 3 represents greatest impact scores. Some questions are linked. The total score ranges from 0 to 27 where a higher score indicates more depression.
Change from Baseline in the Montgomery-Asberg Depression Rating Scale (MADRS) total score.Baseline to Weeks 1-3 and 1- and 2- Week Follow-upThe MADRS is a 10-item depression rating scale used to assess the severity of depression. Individual items are scored on a 7-point scale (0 to 6). The toal score is the sum of individual items, ranging from 0 to 60; where a higher score indicates more depression.
Change from Baseline in 17-item-Hamilton Depression Rating Scale (HAM-D-17) total score.Baseline to Weeks 2 and 4The 17-item HAM-D is used to assess the severity of depression. Individual items are scored on either a 3-point (0 to 2) or a 5-point scale (0 to 4), with 0=No difficulty/absent and 4=most severe. The total score is the sum of individual items, ranging from 0 to 52; where a higher score indicates more depression.
Change from Baseline in Sheehan Disability Scale (SDS) total score.Baseline to Weeks 2 and 4The SDS is a 3-part scale that measures the degree of disruption on work, social and family life using an 11-point scale where 0 represents "no disruption" and 10 represents "extreme disruption". In addition to the 11-point scale, participants are asked to indicate the number of days in the past week that were "lost" and numbers of days that were "underproductive". The results of these questions have a range from 0 to 7. A total global functioning impairment score can be utilized by summing the scores from work, social and family life scales for a value range from 0 to 30.
Change from Baseline in Symbol Digit Modalities Test (SDMT) score.Baseline to Weeks 2 and 4The SDMT is an assessment of complex scanning and visual tracking requiring elements of attention, visuoperceptual processing, working memory, and cognitive/psychomotor speed. The SDMT measures the time to pair abstract symbols with specific numbers. The number of correct substitutions within 90 seconds is recorded and the total score is derived from the total number of correct responses with a minimum possible score of 0 and maximum of 110 where high scores indicate better outcome.
Incidence rates of treatment emergent adverse events (TEAEs), serious adverse events (SAEs), and TEAEs leading to withdrawal from study.Baseline to Weeks 1-4 and 1- and 2- Week Follow up

Countries

United States

Contacts

STUDY_DIRECTORGreg Rigdon, PhD

Sirtsei Pharmaceuticals, Inc.

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Aug 19, 2026