PD, PK, and Safety of ALTO-203 in Patients With MDD
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Phase
Phase 2
Status
Completed
Study type
Interventional
Design
Randomized · Quadruple · Treatment
Enrollment
69actual
Sites
15
Country
United States
Every value on this page is a field the sponsor filed with ClinicalTrials.gov, reproduced. Dates are their own estimates, revised as a study runs, unless the registry marks them actual. sources →
Source: ClinicalTrials.gov, retrieved 2026-08-19
Dates
each axis at the precision it was filed, with the registry's own basis| Date | Filed | Basis | What it is |
|---|---|---|---|
| Start | 2024-03-25 | actual | When the study began enrolling |
| Primary completion | 2025-04-14 | actual | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | 2025-04-21 | actual | The whole study's end, after follow-up |
| First posted | 2024-04-30 | actual | When this record first appeared on the registry |
| Results posted | — | When the sponsor posted results to the registry | |
| Record updated | 2026-04-17 | actual | The sponsor's own last edit to this record — every projection above is as current as this date |
What it studies
Conditions
- Major Depressive Disorder
- Anhedonia
Interventions
- Drug: ALTO-203 25 μg
- Drug: ALTO-203 75 μg
- Drug: Placebo
Primary outcomes
what the primary-completion date above is the date OFSingle Dose Period: To evaluate pharmacodynamic measures in patients with MDD after single doses of 25 μg ALTO-203, 75 μg ALTO-203, and placebo as measured by the alertness and mood components of the Bond-Lader Visual Analog Scale (BL-VAS).
measured Single-Dose Treatment Period - Pre-Dose, 1.5 hours, 3 hours, and 5 hours on Day 1 at Treatments 1, 2, and 3
Multi-Dose Period: To assess the incidence of Treatment-Emergent Adverse Events [Safety and Tolerability] during the multi-dose treatment period for ALTO-203 25 μg and ALTO-203 75 μg as compared to placebo.
measured Multi-Dose Treatment Period Day 1 to Day 35
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