PD, PK, and Safety of ALTO-203 in Patients With MDD

NCT ID: NCT06391593

Last Updated: 2025-10-17

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

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Recruitment Status

COMPLETED

Clinical Phase

PHASE2

Total Enrollment

69 participants

Study Classification

INTERVENTIONAL

Study Start Date

2024-03-25

Study Completion Date

2025-04-21

Brief Summary

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The goal of this clinical trial is to determine the pharmacodynamic effects of ALTO-203 in patients with MDD in a randomized, placebo-controlled, single-dose crossover treatment period. Additionally, safety, tolerability, and PK will be assessed in a subsequent randomized placebo-controlled multi-dose parallel-group treatment period of 28 days.

Participants will complete subjective response questionnaires and perform cognitive tasks during the single-dose period, in which participants will receive ALTO-203 25 μg and 75 μg, as well as placebo. During the multiple-dose period, participants will receive either ALTO-203 25 μg, 75 μg , or placebo. Safety will be assessed over the single dose and 28-day multiple dose periods.

Detailed Description

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Conditions

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Major Depressive Disorder Anhedonia

Study Design

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Allocation Method

RANDOMIZED

Intervention Model

CROSSOVER

The study will consist of two treatment periods. The initial Single-Dose Treatment Period is a randomized, double-blind, placebo-controlled 3-way crossover design with oral administration of a single dose of ALTO-203 25 μg, ALTO-203 75 μg, and matching placebo. In the subsequent Multi-Dose Parallel-Group Treatment Period, participants will receive ALTO-203 25 μg, ALTO-203 75 μg, or matching placebo randomized 1:1:1 for a total of 28 days.
Primary Study Purpose

TREATMENT

Blinding Strategy

QUADRUPLE

Participants Caregivers Investigators Outcome Assessors

Study Groups

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ALTO-203 25 μg

Drug: ALTO-203 25 μg

Single-Dose Treatment Period: Single Dose, ALTO-203 25 μg

Multi-Dose Treatment Period: ALTO-203 25 μg, administered orally, once daily for 28 days

Group Type EXPERIMENTAL

ALTO-203 25 μg

Intervention Type DRUG

Active, ALTO-203 25 μg

ALTO-203 75 μg

Drug: ALTO-203 75 μg

Single-Dose Treatment Period: Single Dose, ALTO-203 75 μg

Multi-Dose Treatment Period: ALTO-203 75 μg, administered orally, once daily for 28 days

Group Type EXPERIMENTAL

ALTO-203 75 μg

Intervention Type DRUG

Active, ALTO-203 75 μg

Placebo

Drug: Placebo

Single-Dose Treatment Period: Single Dose, Placebo

Multi-Dose Treatment Period: Placebo, administered orally, once daily for 28 days

Group Type PLACEBO_COMPARATOR

Placebo

Intervention Type DRUG

Comparator, Placebo-to-match

Interventions

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ALTO-203 25 μg

Active, ALTO-203 25 μg

Intervention Type DRUG

ALTO-203 75 μg

Active, ALTO-203 75 μg

Intervention Type DRUG

Placebo

Comparator, Placebo-to-match

Intervention Type DRUG

Eligibility Criteria

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Inclusion Criteria

* Have a diagnosis of moderate major depressive disorder (MDD)
* Presence of anhedonia symptoms
* Not taking antidepressant at Screening Visit 2
* Willing to comply with all study assessments and procedures

Exclusion Criteria

* Evidence of unstable medical condition
* Diagnosed bipolar disorder, psychotic disorder, or dementia
* Concurrent use of prohibited medications
* Current moderate or severe substance use disorder
* Concurrent or recent participation in another clinical trial for mental illness involving an investigational product or device
Minimum Eligible Age

25 Years

Maximum Eligible Age

64 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

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Alto Neuroscience

INDUSTRY

Sponsor Role lead

Responsible Party

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Responsibility Role SPONSOR

Locations

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Site 4058

Tucson, Arizona, United States

Site Status

Site 4082

Oceanside, California, United States

Site Status

Site 4023

Torrance, California, United States

Site Status

Site 4059

Clermont, Florida, United States

Site Status

Site 4005

Orlando, Florida, United States

Site Status

Site 4031

Atlanta, Georgia, United States

Site Status

Site 4054

Pikesville, Maryland, United States

Site Status

Site 4036

Las Vegas, Nevada, United States

Site Status

Site 4022

Marlton, New Jersey, United States

Site Status

Site 4134

Princeton, New Jersey, United States

Site Status

Site 4075

Westlake, Ohio, United States

Site Status

Site 4040

Austin, Texas, United States

Site Status

Site 4072

Houston, Texas, United States

Site Status

Site 4007

Clinton, Utah, United States

Site Status

Site 4033

Bellevue, Washington, United States

Site Status

Countries

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United States

Other Identifiers

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ALTO-203-201

Identifier Type: -

Identifier Source: org_study_id

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