Study of ALTO-300 in MDD

NCT05922878 | Recruiting Phase 2 FDA Drug

• 1 other identifier: ALTO-300-201
• Study Type: interventional
• Target: 321
• Locations: 1 country
• Sites: 45

Brief Summary

The purpose of this study is to determine efficacy differences between ALTO-300 and placebo, used adjunctively to an antidepressant, related to patient characteristics.

Conditions

Major Depressive Disorder

Outcome Measures

Primary Outcomes (1)

• To assess efficacy of adjunctive ALTO-300 versus placebo on symptoms of MDD in a pre-defined subgroup of participants as measured by the change over time up to week 6 in the Montgomery-Åsberg Depression Rating Scale (MADRS).

  MADRS is a clinician-administered scale designed to measure depression severity and detects changes due to antidepressant treatment. The MADRS evaluates the following 10 items: apparent sadness, reported sadness, inner tension, reduced sleep, reduced appetite, concentration difficulties, lassitude, inability to feel, pessimistic thoughts, and suicidal thoughts. Each item is scored from 0 (item not present or normal) to 6 (severe or continuous presence of the symptoms), for a total possible score of 60. Higher scores represent a more severe condition.

  Change over time for up to week 6

Secondary Outcomes (7)

• To assess efficacy of adjunctive ALTO-300 versus placebo on symptoms of MDD in all randomized participants as measured by the change over time up to week 6 in the Montgomery-Åsberg Depression Rating Scale (MADRS)

  Change over time for up to week 6

• To assess efficacy of adjunctive ALTO-300 versus placebo for MDD as measured by the change over time up to week 6 in response (>50% improvement from baseline) rates based on the MADRS

  Change over time for up to week 6

• To evaluate the safety of ALTO-300 during both the OL and DB periods of the study as measured by the assessment of the incidence, severity, and relatedness of Adverse Events.

  Assessed from Day 1 to Week 14

• To evaluate the safety of ALTO-300 during both the OL and DB periods of the study as measured by the assessment of Heart Rate.

  Assessed from Day 1 to Week 14

• To evaluate the safety of ALTO-300 during both the OL and DB periods of the study as measured by the assessment of Weight.

  Assessed from Day 1 to Week 14

Study Arms (2)

ALTO-300

EXPERIMENTAL

Participants will receive ALTO-300 capsule once daily in the evening, from Day 1 to Day 42 in double blind (DB) treatment period. Eligible participants who will enter the open-label (OL) treatment period will receive ALTO-300 capsule once daily in the evening from OL baseline until the end of OL period/early termination visit (Up to 8 weeks).

Drug: ALTO-300

Placebo

PLACEBO COMPARATOR

Participants will receive matching placebo capsule once daily in the evening, from Day 1 to Day 42 in double blind (DB) treatment period.

Drug: Placebo

Interventions

ALTO-300 DRUG

ALTO-300 capsule QD

ALTO-300

Placebo DRUG

Placebo capsule QD

Placebo

Eligibility Criteria

• Age: 18 Years - 70 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Have a diagnosis of moderate to severe major depressive disorder (MDD)
• At Visit 1, currently taking a single SSRI, SNRI, or bupropion for at least 6 weeks with no dose modifications in the past 2 weeks by Visit 2
• Willing to comply with all study assessments and procedures
• Must not be pregnant or breastfeeding at time of enrollment or throughout study

You may not qualify if:

• Evidence of unstable medical condition
• Nightly use of sleep medication
• Diagnosed bipolar disorder, psychotic disorder, or dementia
• Current moderate or severe substance use disorder
• Has a history of hypersensitivity or allergic reaction to ALTO-300 or any of its components/excipients
• Concurrent or recent participation in another clinical trial for mental illness involving an investigational product or device

Sponsors & Collaborators

• Alto Neuroscience: lead

Study Sites (45)

Site 200

Phoenix, Arizona, 85012, United States

RECRUITING

Site 189

Phoenix, Arizona, 85021, United States

WITHDRAWN

Site 187

Yuma, Arizona, 85364, United States

RECRUITING

Site 193

Rogers, Arkansas, 72758, United States

RECRUITING

Site 218

Bellflower, California, 90706, United States

RECRUITING

Site 217

Glendale, California, 91206, United States

RECRUITING

Site 335

Lafayette, California, 94549, United States

RECRUITING

Site 209

Los Angeles, California, 90064, United States

RECRUITING

Site 219

Mather, California, 95655, United States

RECRUITING

Site 194

Mission Viejo, California, 92691, United States

RECRUITING

Site 197

Temecula, California, 92591, United States

RECRUITING

Site 203

Colorado Springs, Colorado, 80918, United States

RECRUITING

Site 349

Evergreen, Colorado, 80439, United States

RECRUITING

Site 214

Norwalk, Connecticut, 06851, United States

RECRUITING

Site 159

Clermont, Florida, 34711, United States

RECRUITING

Site 225

Miami Gardens, Florida, 33014, United States

RECRUITING

Site 190

Miami Lakes, Florida, 33016, United States

RECRUITING

Site 161

Okeechobee, Florida, 34972, United States

RECRUITING

Site 221

Tampa, Florida, 33629, United States

RECRUITING

Site 220

West Palm Beach, Florida, 33407, United States

RECRUITING

Site 224

Savannah, Georgia, 31405, United States

RECRUITING

Site 208

Snellville, Georgia, 30078, United States

RECRUITING

Site 119

Boise, Idaho, 83702, United States

RECRUITING

Site 310

Chicago, Illinois, 60634, United States

RECRUITING

Site 201

Marrero, Louisiana, 70072, United States

TERMINATED

Site 198

Monroe, Louisiana, 71201, United States

TERMINATED

Site 215

Jackson, Mississippi, 39216, United States

RECRUITING

Site 344

Las Vegas, Nevada, 89102, United States

RECRUITING

Site 114

Albuquerque, New Mexico, 87108, United States

RECRUITING

Site 191

Rochester, New York, 14618, United States

TERMINATED

Site 192

Staten Island, New York, 10314, United States

RECRUITING

Site 199

Hickory, North Carolina, 28601, United States

RECRUITING

Site 202

Cincinnati, Ohio, 45215, United States

RECRUITING

Site 195

Oklahoma City, Oklahoma, 73112, United States

RECRUITING

Site 216

Allentown, Pennsylvania, 18104, United States

RECRUITING

Site 350

Media, Pennsylvania, 19063, United States

RECRUITING

Site 352

Moosic, Pennsylvania, 18507, United States

RECRUITING

Site 102

Dallas, Texas, 75235, United States

WITHDRAWN

Site 347

Fort Worth, Texas, 76104, United States

RECRUITING

Site 148

Fort Worth, Texas, 76244, United States

WITHDRAWN

Site 206

Missouri City, Texas, 77459, United States

WITHDRAWN

Site 353

Plano, Texas, 75093, United States

NOT YET RECRUITING

Site 196

Richmond, Texas, 77407, United States

RECRUITING

Site 207

Clinton, Utah, 84015, United States

RECRUITING

Site 211

Roanoke, Virginia, 24018, United States

RECRUITING

MeSH Terms

Conditions

Depressive Disorder, Major

Condition Hierarchy (Ancestors)

Depressive Disorder; Mood Disorders; Mental Disorders

Study Officials

• Adam Savitz, MD, PhD

  Alto Neuroscience

  STUDY DIRECTOR

Central Study Contacts

Alto Neuroscience

CONTACT

650-200-0412; clinical@altoneuroscience.com

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 26, 2023
• First Posted: June 28, 2023
• Study Start: June 8, 2023
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): December 1, 2026
• Last Updated: July 24, 2025

Record last verified: 2025-06

Locations

US (45)