A Trial of the Efficacy and Safety of Fixed Doses of SEP-363856 in Adults With Generalized Anxiety Disorder

Otsuka

Status and phase: Enrolling; Phase 3

Conditions: Generalized Anxiety Disorder

Treatments: Drug: SEP-363856; Other: Placebo

Study type: Interventional

Funder types: Industry

Identifiers

NCT07759128

382-201-00032

2026-526033-25-00 (EU Trial (CTIS) Number)

Details and patient eligibility

About

This is a global, phase 3, randomized, double-blind, parallel-group, 3-arm, placebo-controlled, multicenter study designed to compare the efficacy, safety, and tolerability of fixed doses of SEP-363856 (50 and 75 milligrams per day [mg/day]) to placebo in adults at least 18 years of age with generalized anxiety disorder (GAD) over 8 weeks.

Enrollment: 576 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion and exclusion criteria

Key Inclusion Criteria:

1. Male or female participants at least 18 years of age at the time of informed consent
2. Primary diagnosis of Generalized Anxiety Disorder (GAD) per Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), confirmed by Mini-International Neuropsychiatric Interview (MINI) and clinical psychiatric evaluation
3. Body Mass Index (BMI) between 18 and 40 kilograms per square meter (kg/m^2) (inclusive)
4. Participant is willing and able to comply with study procedures and visit schedule
5. Medically stable as determined by medical history, physical exam, vital signs, and laboratory tests
6. Willing and able to discontinue prohibited medications/therapies per protocol
7. i) Females of childbearing potential: negative pregnancy test and agreement to use acceptable contraception ii) Males: agreement to follow protocol-defined contraception and reproductive restrictions
8. Participant is willing and able to safely discontinue all prohibited medications/therapies/herbal supplements in accordance with the protocol-required washouts prior to baseline/Day 1 and during the trial period.

Key Exclusion Criteria:

1. Current DSM-5 diagnosis of major depressive episode, post traumatic stress disorder (PTSD), or any psychiatric disorder other than GAD that was the primary focus of treatment within 12 months prior to screening
2. Substance use disorder (excluding nicotine/caffeine) within 12 months prior to screening
3. Lifetime history of certain psychiatric disorders (e.g., schizophrenia spectrum disorders, bipolar disorder, obsessive-compulsive disorder, borderline or antisocial personality disorder)
4. Significant suicide risk (e.g., recent suicidal behavior/ideation per Columbia-Suicide Severity Rating Scale [C-SSRS] or MADRS)
5. Use of prohibited medications/therapies within protocol-defined timeframes (e.g., certain antipsychotics, mood stabilizers, benzodiazepines, investigational treatments)
6. Prior exposure to restricted treatments
7. Pregnant or breastfeeding females
8. Participation in another investigational study within 180 days (or more than [>] 1 trial in last year)
9. Known history of human immunodeficiency virus seropositivity, hepatitis B or C

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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576 participants in 3 patient groups, including a placebo group

SEP-363856 50 mg

Experimental group

Description:

Participants will receive 50 milligrams (mg) SEP-363856 tablet, orally, once a day (QD) from Days 1 to 56.

Treatment:

Drug: SEP-363856

SEP-363856 75 mg

Experimental group

Description:

Participants will receive 50 mg SEP-363856 tablet, orally, QD, from Days 1 to 3 and then 75 mg tablet from Days 4 to 56.

Treatment:

Drug: SEP-363856

Placebo

Placebo Comparator group

Description:

Participants will receive SEP-363856-matching placebo tablet, orally, QD from Days 1 to 56.

Treatment:

Other: Placebo