SEP-363856 · program
Ulotaront (SEP-363856) for Generalized anxiety disorder
Indications for SEP-363856: Generalized anxiety disorder · Phase 2/3 Major depressive disorder · Phase 2/3
Phase 2/3 ulotaront monotherapy in generalized anxiety disorder (SEP361-226 / NCT05729373, n=434, HAM-A primary), completed 26 Sep 2025; topline pending. A Phase 2/3 adjunctive MDD program (NCT05593029, n=929) also completed (Nov 2025). Otsuka committed to continuing GAD/MDD development after the 2023 schizophrenia Phase 3 failure.
Development timeline
Phase 2/3Mar 2023 – Sept 2025
- Phase 2/3 GAD study (NCT05729373) reached completion; topline results not yet disclosed.
- Sumitomo Pharma amended its worldwide license; Otsuka took over ulotaront (incl. GAD/MDD) and decided to continue development.↗
- First patient randomized in the Phase 2/3 GAD study (NCT05729373).
Clinical trials in Generalized anxiety disorder
NCT05729373SEP361-226Phase 2/3Completedn=434
Phase 2/3 Study of SEP-363856 in Generalized Anxiety Disorder
Formulations
| Formulation | Route | Regimen | Pharmacokinetics |
|---|---|---|---|
| Ulotaront oral Oral doses studied 10-100 mg (dose-proportional PK); 25 mg single oral dose in the CYP2D6 healthy-subject study; once-daily dosing supported by PK. | Oral | Once daily | t½ 7 h · Tmax 2 h |
Mechanism of action
Dual TAAR1 agonist / 5-HT1A agonist with no appreciable D2 or 5-HT2A activity.
| Target | Action | Affinity |
|---|---|---|
| TAAR1primaryTAAR1 | Agonist | EC50 38 nMⓘ |
| 5-HT1AHTR1A | Agonist | Ki 284 nMⓘ |
← Full SEP-363856 compound page (identity, identifiers, all indications)
Sources
- A Phase I, Open-Label, Fixed Sequence Study to Investigate the Effect of CYP2D6 Inhibition on the Pharmacokinetics of Ulotaront in Healthy Subjects — Clinical Pharmacokinetics (PMC)
- Sumitomo→Otsuka license amendment (ulotaront) — Sumitomo Pharma
- Ulotaront Phase 2/3 GAD (NCT05729373) — ClinicalTrials.gov
- Ulotaront: A TAAR1 Agonist for the Treatment of Schizophrenia (synthesis/med-chem) — ACS Med Chem Lett (PMC)