A Study to Assess the Long-term Efficacy and Safety of AXS-12 (Reboxetine) in Subjects With Narcolepsy (ENCORE)

November 11, 2025 updated by: Axsome Therapeutics, Inc.

A Study to Assess the Long-term Efficacy and Safety of AXS-12 in the Treatment of Cataplexy and Excessive Daytime Sleepiness in Subjects With Narcolepsy

This study will evaluate the long-term efficacy and safety of AXS-12 in narcoleptic subjects with cataplexy and excessive daytime sleepiness (EDS).

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

This study is a multi-center trial consisting of a 24-week open-label period, followed by a 4-week double-blind, placebo-controlled, randomized withdrawal period. At the Week 24 visit, subjects will be randomized in a 1:1 ratio either to continue to receive AXS-12 or to switch to placebo, for the next 4 weeks. Eligible subjects will have previously participated in the AXS-12-301 study.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
68

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • 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 Locations

  • Canada
    • Ontario
      • Toronto, Ontario, Canada, M5S 3A3
        • Clinical Research Site
  • United States
    • Arizona
      • Phoenix, Arizona, United States, 85054
        • Clinical Research Site
    • Colorado
      • Boulder, Colorado, United States, 80301
        • Clinical Research Site
      • Colorado Springs, Colorado, United States, 80918
        • Clinical Research Site
    • Florida
      • Brandon, Florida, United States, 33511
        • Clinical Research Site
      • Clearwater, Florida, United States, 33765
        • Clinical Research Site
      • Doral, Florida, United States, 33122
        • Clinical Research Site
      • Miami Lakes, Florida, United States, 33016
        • Clinical Research Site
      • Winter Park, Florida, United States, 32789
        • Clinical Research Site
    • Georgia
      • Atlanta, Georgia, United States, 30328
        • Clinical Research Site
      • Atlanta, Georgia, United States, 30315
        • Clinical Research Site
      • Stockbridge, Georgia, United States, 30281
        • Clinical Research Site
    • Maryland
      • Chevy Chase, Maryland, United States, 20815
        • Clinical Research Site
    • Michigan
      • Kalamazoo, Michigan, United States, 49008
        • Clinical Research Site
      • Novi, Michigan, United States, 48377
        • Clinical Research Site
    • New Jersey
      • Neptune City, New Jersey, United States, 07753
        • Clinical Research Site
    • North Carolina
      • Denver, North Carolina, United States, 28037
        • Clinical Research Site
      • Gastonia, North Carolina, United States, 28054
        • Clinical Research Site
      • Huntersville, North Carolina, United States, 28078
        • Clinical Research Site
    • Ohio
      • Cincinnati, Ohio, United States, 45245
        • Clinical Research Site
    • Pennsylvania
      • Wyomissing, Pennsylvania, United States, 19610
        • Clinical Research Site
    • South Carolina
      • Charleston, South Carolina, United States, 29425
        • Clinical Research Site
      • Columbia, South Carolina, United States, 29201
        • Clinical Research Site
    • Texas
      • Austin, Texas, United States, 78731
        • Clinical Research Site
      • San Antonio, Texas, United States, 78229
        • 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

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

15 years to 75 years (Child, Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Completed the treatment period of Study AXS-12-301
  • Willing and able to comply with the study requirements

Exclusion Criteria:

  • Significant change in medical history or concomitant medications since enrolling in the AXS-12-301 study which, in the opinion of the Investigator, would render the subject unsuitable to receive AXS-12

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

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: AXS-12 (reboxetine)
  • Up to 24 weeks in open-label period
  • Up to 4 weeks in randomized double-blind period
Drug: AXS-12 (reboxetine)
AXS-12 tablets, taken twice daily
Placebo Comparator: Placebo
Up to 4 weeks in randomized double-blind period
Drug: Placebo
Placebo tablets, taken twice daily

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Time Frame
Long-term safety as measured by the incidence of treatment-emergent adverse events
Time Frame: Up to 28 weeks
Up to 28 weeks
Efficacy as measured by change in frequency of cataplexy attacks from baseline.
Time Frame: Baseline to Week 27
Baseline to Week 27

Collaborators and Investigators

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

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
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)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
October 20, 2021

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
November 15, 2024

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
November 15, 2024

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
October 29, 2021

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
October 29, 2021

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
November 9, 2021

Study Record Updates

Last Update Posted (Estimated)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
November 13, 2025

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 11, 2025

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
November 1, 2025

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • AXS-12-302

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

product manufactured in and exported from the U.S.

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.

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