Studying NMDA and Sigma-1 in Smoking Cessation Treatment (SUMMIT) (SUMMIT)

September 3, 2026 updated by: Axsome Therapeutics, Inc.

A Randomized, Double-Blind, Placebo and Active-Controlled Trial to Evaluate the Efficacy and Safety of AXS-05 for Smoking Cessation in Adults

This study is a Phase 3, multicenter, randomized, double-blind, placebo- and active-controlled, parallel-group trial to evaluate the efficacy and safety of AXS-05 compared to placebo and bupropion for smoking cessation in adults.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Detailed Description

Eligible subjects will be randomized in a 1:1:1 ratio to receive AXS-05, bupropion, or placebo for 12 weeks, followed by an 18-week follow-up period.

Study Type

Interventional

Enrollment (Estimated)

705

Phase

  • Phase 3

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

  • United States
    • Arkansas
      • Little Rock, Arkansas, United States, 72211
        • Recruiting
        • Clinical Research Site
    • California
      • Lemon Grove, California, United States, 91945
        • Recruiting
        • Clinical Research Site
      • Pomona, California, United States, 91767
        • Recruiting
        • Clinical Research Site
    • Florida
      • DeLand, Florida, United States, 32720
        • Recruiting
        • Clinical Research Site
      • Jacksonville, Florida, United States, 32256
        • Recruiting
        • Clinical Research Site
      • Orlando, Florida, United States, 32801
        • Recruiting
        • Clinical Research Site
    • Georgia
      • Stockbridge, Georgia, United States, 30281
        • Recruiting
        • Clinical Research Site
    • Illinois
      • Skokie, Illinois, United States, 60077
        • Recruiting
        • Clinical Research Site
    • Indiana
      • Evansville, Indiana, United States, 47714
        • Recruiting
        • Clinical Research Site
    • Missouri
      • Kansas City, Missouri, United States, 64114
        • Recruiting
        • Clinical Research Site
    • New York
      • Brooklyn, New York, United States, 11235
        • Recruiting
        • Clinical Research Site
    • Tennessee
      • Knoxville, Tennessee, United States, 37909
        • Recruiting
        • Clinical Research Site
      • Memphis, Tennessee, United States, 38119
        • Recruiting
        • Clinical Research Site
    • Texas
      • Austin, Texas, United States, 78705
        • Recruiting
        • Clinical Research Site
      • Fort Worth, Texas, United States, 76135
        • Recruiting
        • Clinical Research Site
    • Virginia
      • Newport News, Virginia, United States, 23606
        • Recruiting
        • Clinical Research Site

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Male or female, aged 18 to 65 (inclusive)

Exclusion Criteria:

  • Unable to comply with study procedures.
  • Medically inappropriate for study participation in the opinion of the investigator.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Placebo Comparator: Placebo
Up to 12 weeks
Drug: Placebo
Placebo tablets, taken twice daily for 12 weeks.
Experimental: AXS-05
Up to 12 weeks
Drug: AXS-05 (dextromethorphan-bupropion)
AXS-05 tablets, taken twice daily for 12 weeks.
Experimental: Bupropion
Up to 12 weeks
Drug: Bupropion
Bupropion tablets, taken twice daily for 12 weeks.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
4-Week Continuous Smoking Abstinence Rate
Time Frame: Weeks 9 to 12
Weeks 9 to 12

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Axsome Therapeutics, Inc.

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

August 27, 2026

Primary Completion (Estimated)

December 1, 2027

Study Completion (Estimated)

December 1, 2027

Study Registration Dates

First Submitted

August 11, 2026

First Submitted That Met QC Criteria

August 11, 2026

First Posted (Actual)

August 14, 2026

Study Record Updates

Last Update Posted (Actual)

September 8, 2026

Last Update Submitted That Met QC Criteria

September 3, 2026

Last Verified

September 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • AXS-05-SC-301

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Subscribe