Extension Trial to Evaluate the Long-term Efficacy, Safety, and Tolerability of Maridebart Cafraglutide (MARITIME-1-EXTENSION)

September 2, 2026 updated by: Amgen

A Phase 3, Randomized, Double-Blind Extension Trial to Evaluate the Long-term Efficacy, Safety, and Tolerability of Maridebart Cafraglutide in Participants With Obesity or Overweight

The primary objective of this trial is to evaluate the long-term efficacy, safety, and tolerability of maridebart cafraglutide in participants with obesity or overweight. Trial 20250197 is an extension of trial 20210181 (NCT06858839).

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

3200

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

  • Australia
    • New South Wales
      • Botany, New South Wales, Australia, 2019
        • Recruiting
        • Emeritus Research Sydney
      • Charlestown, New South Wales, Australia, 2290
        • Recruiting
        • Novatrials
      • Miranda, New South Wales, Australia, 2228
        • Recruiting
        • Canopy Clinical Sutherland
      • Wollongong, New South Wales, Australia, 2500
        • Recruiting
        • Canopy Clinical Wollongong
    • South Australia
      • Norwood, South Australia, Australia, 5067
        • Recruiting
        • Fusion Clinical Research
    • Victoria
      • Camberwell, Victoria, Australia, 3124
        • Recruiting
        • Emeritus Research Camberwell
      • North Altona, Victoria, Australia, 3025
        • Recruiting
        • Canopy Clinical Altona North
  • Japan
    • Kanagawa
      • Yokohama, Kanagawa, Japan, 231-0023
        • Recruiting
        • Medical Corporation Hitomikai Motomachi Takatsuka Naika Clinic
    • Tokyo
      • Chiyoda-ku, Tokyo, Japan, 101-0041
        • Recruiting
        • Doujin Memorial Foundation, Meiwa Hospital
      • Chuo-ku, Tokyo, Japan, 104-0031
        • Recruiting
        • Tokyo Asbo Clinic
      • Hachioji-shi, Tokyo, Japan, 192-0046
        • Recruiting
        • Medical Corp Seikoukai New Medical Research System Clinic
      • Minato-ku, Tokyo, Japan, 108-0075
        • Recruiting
        • Medical Corporation AOT Shinagawa Strings Clinic
      • Shinjuku-ku, Tokyo, Japan, 160-0004
        • Recruiting
        • Clinical Research Hospital Tokyo
      • Suginami-ku, Tokyo, Japan, 166-0003
        • Recruiting
        • Medical Corporation Hanabusakai Shinei Medical Healthcare Clinic
  • Puerto Rico
      • Ponce, Puerto Rico, 00716
        • Recruiting
        • Ponce Medical School Foundation Inc
      • Ponce, Puerto Rico, 00717
        • Recruiting
        • Puerto Rico Medical Research Inc.
      • San Juan, Puerto Rico, 00909
        • Recruiting
        • Latin Clinical Trial Center
  • United States
    • Alabama
      • Anniston, Alabama, United States, 36207
        • Recruiting
        • Pinnacle Research Group LLC
      • Daphne, Alabama, United States, 36526
        • Recruiting
        • Alliance For Multispecialty Research - Daphne
      • Mobile, Alabama, United States, 36608
        • Recruiting
        • Alliance for Multispecialty Research Mobile
    • California
      • Fountain Valley, California, United States, 92708
        • Recruiting
        • Ark Clinical Research- Tustin
      • Long Beach, California, United States, 90806
        • Recruiting
        • Long Beach Clinical Trials Services Inc
      • Long Beach, California, United States, 90815
        • Recruiting
        • Ark Clinical Research- Long Beach
      • Montclair, California, United States, 91763
        • Recruiting
        • Catalina Research Institute
      • Riverside, California, United States, 92503
        • Recruiting
        • Artemis Institute for Clinical Research
      • San Diego, California, United States, 92120
        • Recruiting
        • Apex Clinical Research
      • San Diego, California, United States, 92123
        • Recruiting
        • Artemis Institute for Clinical Research
      • Santa Ana, California, United States, 92701
        • Recruiting
        • Southern California Clinical Research
      • Walnut Creek, California, United States, 94598
        • Recruiting
        • Diablo Clinical Research
    • Connecticut
      • Waterbury, Connecticut, United States, 06708
        • Recruiting
        • Chase Medical Research LLC
    • Florida
      • Jacksonville, Florida, United States, 32216
        • Recruiting
        • Jacksonville Center for Clinical Research
      • Jacksonville, Florida, United States, 32256
        • Recruiting
        • Clinical Neuroscience Solutions - Jacksonville
      • Margate, Florida, United States, 33063
        • Recruiting
        • South Florida Wellness and Clinical Research Institute
      • Miami, Florida, United States, 33173
        • Recruiting
        • Research Institute of South Florida
      • Miami, Florida, United States, 33135
        • Recruiting
        • Optimus U Corporation
      • Miami Lakes, Florida, United States, 33016
        • Recruiting
        • Indago Research and Health Center
      • Ocala, Florida, United States, 34470
        • Recruiting
        • Renstar Medical Research
      • Orlando, Florida, United States, 32801
        • Recruiting
        • Clinical Neuroscience Solutions - Orlando
      • Orlando, Florida, United States, 32825
        • Recruiting
        • Florida Institute for Clinical Research
      • Orlando, Florida, United States, 32807
        • Recruiting
        • Combined Research Orlando Phase I IV
      • Weston, Florida, United States, 33331
        • Recruiting
        • Encore Medical Research of Weston LLC
    • Georgia
      • Gainesville, Georgia, United States, 30501
        • Recruiting
        • Center for Advanced Research and Education
      • Union City, Georgia, United States, 30291
        • Recruiting
        • Rophe Adult and Pediatric Medicine/Sky Clinical Research Network Group
    • Hawaii
      • Honolulu, Hawaii, United States, 96814
        • Recruiting
        • East-West Medical Research
    • Idaho
      • Meridian, Idaho, United States, 83646
        • Recruiting
        • Solaris Clinical Research
    • Illinois
      • Chicago, Illinois, United States, 60640
        • Recruiting
        • Flourish Research - Great Lakes Clinical Trials
      • Skokie, Illinois, United States, 60077
        • Recruiting
        • Evanston Premier Healthcare Research LLC
      • Skokie, Illinois, United States, 60077
        • Recruiting
        • Endeavor Health
    • Kansas
      • Newton, Kansas, United States, 67114
        • Recruiting
        • Alliance for Multispecialty Research Newton
    • Kentucky
      • Louisville, Kentucky, United States, 40213
        • Recruiting
        • Monroe Biomedical Research
    • Louisiana
      • Baton Rouge, Louisiana, United States, 70809
        • Recruiting
        • Velocity Clinical Research - Baton Rouge
      • Marrero, Louisiana, United States, 70072
        • Recruiting
        • Tandem Clinical Research - Marrero
    • Michigan
      • Southfield, Michigan, United States, 48034
        • Recruiting
        • Headlands Research - Detroit
    • Mississippi
      • Fayette, Mississippi, United States, 39069
        • Recruiting
        • Prime Health and Wellness Sky Clinical Research Network Group
    • Missouri
      • Kansas City, Missouri, United States, 64114
        • Recruiting
        • Alliance for Multispecialty Research - Kansas City
    • Nevada
      • Las Vegas, Nevada, United States, 89128
        • Recruiting
        • Palm Research Center Inc
      • Las Vegas, Nevada, United States, 89128
        • Recruiting
        • Vector Clinical Trials
    • New York
      • Binghamton, New York, United States, 13905
        • Recruiting
        • Velocity Clinical Research- Binghamton
      • Rochester, New York, United States, 14609
        • Recruiting
        • Rochester Clinical Research
    • North Carolina
      • Hickory, North Carolina, United States, 28601
        • Recruiting
        • Accellacare of Hickory
      • Shelby, North Carolina, United States, 28150
        • Recruiting
        • Carolina Research Center Inc
    • Ohio
      • Cincinnati, Ohio, United States, 45219
        • Recruiting
        • Velocity Clinical Research - Cincinnati
      • Cincinnati, Ohio, United States, 45212
        • Recruiting
        • Clinical Trial Investigator Clinical Research Center
    • Oklahoma
      • Norman, Oklahoma, United States, 73069
        • Recruiting
        • Alliance for Multispecialty Research - Norman
    • Pennsylvania
      • Newport, Pennsylvania, United States, 17074
        • Recruiting
        • Capital Area Research LLC
    • Rhode Island
      • East Greenwich, Rhode Island, United States, 02818
        • Recruiting
        • Velocity Clinical Research - Providence
    • South Carolina
      • Greenville, South Carolina, United States, 29607
        • Recruiting
        • Tribe Clinical Research LLC Dba Mountain View Clinical Research
    • Tennessee
      • Knoxville, Tennessee, United States, 37909
        • Recruiting
        • New Phase Research and Development
    • Texas
      • Austin, Texas, United States, 78704
        • Recruiting
        • Elligo Clinical Research Center
      • Bellaire, Texas, United States, 77401
        • Recruiting
        • Johnson County Clinical Trials Juno Bellaire
      • Dallas, Texas, United States, 75251
        • Recruiting
        • Cedar Health Research, LLC
      • DeSoto, Texas, United States, 75115
        • Recruiting
        • Epic Medical Research - Red Oak
      • El Paso, Texas, United States, 79936
        • Recruiting
        • Great Lakes Research Institute El Paso Research
      • Euless, Texas, United States, 76040
        • Recruiting
        • Cedar Health Research, LLC
      • Houston, Texas, United States, 77043
        • Recruiting
        • Biopharma Informatic, LLC
      • Houston, Texas, United States, 77040
        • Recruiting
        • JCCT- Juno Northwest Houston
      • Mesquite, Texas, United States, 75149
        • Recruiting
        • Southern Endocrinology Associates PA
      • Pharr, Texas, United States, 78557
        • Recruiting
        • Great Lakes Research Institute - McAllen Research
      • San Antonio, Texas, United States, 78229
        • Recruiting
        • Clinical Trials of Texas
      • Sugar Land, Texas, United States, 77479
        • Recruiting
        • Sugar Lakes Family Practice
    • Utah
      • Bountiful, Utah, United States, 84010
        • Recruiting
        • Pantheon Clinical Research
      • Layton, Utah, United States, 84041
        • Recruiting
        • Alliance for Multispecialty Research Layton Research Center
      • St. George, Utah, United States, 84770
        • Recruiting
        • Chrysalis Clinical Research, LLC
    • Virginia
      • Arlington, Virginia, United States, 22206
        • Recruiting
        • Washington Center for Weight Management and Research, Inc
      • Newport News, Virginia, United States, 23606
        • Recruiting
        • Health Research of Hampton Roads
      • Winchester, Virginia, United States, 22601
        • Recruiting
        • Selma Medical Associates
    • Wisconsin
      • Wauwatosa, Wisconsin, United States, 53226
        • Recruiting
        • Allegiance Research Specialists

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:

  • Signed informed consent form (ICF) which includes compliance with the requirements and restrictions listed in the ICF and in this protocol.
  • Completed the parent trial (2010181)
  • Completed week 72 visit in parent trial
  • Did not permanently discontinue trial intervention in parent trial
  • Randomized within 7 Days of week 72 visit in the parent trial
  • Participants must use protocol-specified contraception during treatment, and for an additional 16 weeks after the last dose of trial intervention

Exclusion Criteria:

  • Planned (during the trial) surgical, endoscopic, or device-based treatment for obesity
  • Body mass index ≤ 18.5 kilograms per meter square (kg/m^2)
  • Participant has known sensitivity to any of the products or components to be administered during dosing
  • History of ischemic optic neuropathy
  • Any malignancy diagnosed during parent trial (20210181) except for the following treated with curative intent: nonmelanoma skin cancers, breast ductal carcinoma in situ, cervical carcinoma in situ, or prostate cancer in situ.
  • Newly identified (i.e., identified during 20210181) multiple endocrine neoplasia syndrome type 2 or family (first-degree relative[s]) history of medullary thyroid cancer.
  • Patient Health Questionnaire-9 (PHQ-9) score of ≥ 15 at week 72 visit from parent trial before randomization
  • Any suicidal ideation of category 4 or 5 OR any suicidal behavior on the Columbia-Suicide Severity Rating Scale (C-SSRS) Since Last Visit version at week 72 visit from parent trial before randomization.
  • Participant unlikely to be able to complete all protocol-required procedures, restrictions and requirements, in the judgment of the individual and investigator.
  • History or evidence of any other clinically significant disorder, condition, or disease (including, but not limited to known drug or alcohol abuse, eating disorders, and conditions identified during the parent trial) that, in the opinion of the investigator, would pose a risk to participant safety.
  • Currently pregnant (confirmed with positive pregnancy test) or breastfeeding or
  • Planning to become pregnant or breastfeed while on trial until an additional 16 weeks after the last dose of trial intervention.
  • Major surgical procedures planned during the trial.
  • Participants with minor surgical procedures (not requiring general anesthesia or deep sedation) planned during the trial may be eligible at the discretion of the investigator.
  • Investigative site personnel directly affiliated with the trial and/or their immediate family (ie, spouse, parent, child, or sibling, whether biological or legally adopted).

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
Experimental: Maridebart Cafraglutide Low Dose Q4W
Participants who received low dose of maridebart cafraglutide in the parent trial (20210181 [NCT06858839]) will continue to receive low dose of maridebart cafraglutide subcutaneously (SC) once in 4 weeks(Q4W).
Drug: Maridebart cafraglutide
Administered subcutaneously
Other Names:
  • AMG 133
  • MariTide
Experimental: Maridebart Cafraglutide Medium Dose Q4W
Participants who received medium dose of maridebart cafraglutide in the parent trial will be re-randomized in this trial to receive medium dose of maridebart cafraglutide SC Q4W.
Drug: Maridebart cafraglutide
Administered subcutaneously
Other Names:
  • AMG 133
  • MariTide
Experimental: Maridebart Cafraglutide Medium Dose Q8W
Participants who received medium dose of maridebart cafraglutide in the parent trial will be re-randomized in this trial to receive medium dose of maridebart cafraglutide SC once in 8weeks (Q8W).
Drug: Maridebart cafraglutide
Administered subcutaneously
Other Names:
  • AMG 133
  • MariTide
Placebo Comparator: Placebo Q4W (Received Medium Dose Maridebart Cafraglutide in Parent Trial)
Participants who received medium dose of maridebart cafraglutide in the parent trial will be re-randomized in this trial to receive placebo SC Q4W.
Drug: Placebo
Administered subcutaneously.
Experimental: Maridebart Cafraglutide High Dose Q4W
Participants who received high dose of maridebart cafraglutide in the parent trial will be re-randomized in this trial to receive high dose of maridebart cafraglutide SC Q4W.
Drug: Maridebart cafraglutide
Administered subcutaneously
Other Names:
  • AMG 133
  • MariTide
Experimental: Maridebart Cafraglutide High Dose Q8W
Participants who received high dose of maridebart cafraglutide in the parent trial will be re-randomized in this trial to receive high dose of maridebart cafraglutide SC Q8W.
Drug: Maridebart cafraglutide
Administered subcutaneously
Other Names:
  • AMG 133
  • MariTide
Experimental: Maridebart Cafraglutide High Dose Q12W
Participants who received high dose of maridebart cafraglutide in the parent trial will be re-randomized in this trial to receive high dose of maridebart cafraglutide SC once in 12 weeks (Q12W).
Drug: Maridebart cafraglutide
Administered subcutaneously
Other Names:
  • AMG 133
  • MariTide
Placebo Comparator: Placebo Q4W (Received High Dose Maridebart Cafraglutide in Parent Trial)
Participants who received high dose of maridebart cafraglutide in the parent trial will be re-randomized in this trial to receive placebo SC Q4W.
Drug: Placebo
Administered subcutaneously.
Experimental: Maridebart Cafraglutide High Dose Q4W (Received Placebo in the Parent Trial)
Participants who received placebo in the parent trial will receive high dose of maridebart cafraglutide SC Q4W. Prior to initiating the assigned high dose, participants will undergo a dose-escalation phase gradually increasing doses.
Drug: Maridebart cafraglutide
Administered subcutaneously
Other Names:
  • AMG 133
  • MariTide
Experimental: Maridebart Cafraglutide Low Dose Q4W(Received Very Low Dose Maridebart Cafraglutide in Parent Trial)
Participants who permanently de-escalated to very low dose of maridebart cafraglutide in the parent trial will receive low dose of maridebart cafraglutide SC Q4W.
Drug: Maridebart cafraglutide
Administered subcutaneously
Other Names:
  • AMG 133
  • MariTide

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Percent Change in Body Weight from Baseline of the Parent Trial (20210181)
Time Frame: Baseline of parent trial (20210181) to Week 48 of current trial
Baseline of parent trial (20210181) to Week 48 of current trial
Number of Participants Experiencing Treatment-emergent Adverse Events (TEAEs) and Serious Adverse Events (SAEs)
Time Frame: Baseline of current trial up to 60 weeks
Baseline of current trial up to 60 weeks

Secondary Outcome Measures

Outcome Measure
Time Frame
Percentage of Participants Achieving ≥5% Reduction in Body Weight from Baseline of the Parent Trial
Time Frame: Baseline of parent trial to Week 48 of current trial
Baseline of parent trial to Week 48 of current trial
Percentage of Participants Achieving ≥10% Reduction in Body Weight from Baseline of the Parent Trial
Time Frame: Baseline of parent trial to Week 48 of current trial
Baseline of parent trial to Week 48 of current trial
Percentage of Participants Achieving ≥15% Reduction in Body Weight from Baseline of the Parent Trial
Time Frame: Baseline of parent trial to Week 48 of current trial
Baseline of parent trial to Week 48 of current trial
Percentage of Participants Achieving ≥20% Reduction in Body Weight from Baseline of the Parent Trial
Time Frame: Baseline of parent trial to Week 48 of current trial
Baseline of parent trial to Week 48 of current trial
Change from Baseline of the Parent Trial in Waist Circumference
Time Frame: Baseline of parent trial to Week 48 of current trial
Baseline of parent trial to Week 48 of current trial
Change from Baseline of the Parent Trial in the Impact of Weight on Quality of Life-Lite Clinical Trials Version (IWQOL-Lite-CT) Physical Function Composite Score
Time Frame: Baseline of parent trial to Week 48 of current trial
Baseline of parent trial to Week 48 of current trial
Percent Change from Baseline in Body Weight
Time Frame: Baseline of current trial to Week 48
Baseline of current trial to Week 48
Percentage of Participants with No Body Weight Gain of >3% From Baseline
Time Frame: Week 48 of current trial
Week 48 of current trial
Percentage of Participants with No Body Weight Gain of >5% From Baseline
Time Frame: Week 48 of current trial
Week 48 of current trial
Percentage of Body Weight Reduction Maintained from the Parent Trial
Time Frame: Baseline of parent trial to Week 48 of current trial
Baseline of parent trial to Week 48 of current trial
Percentage of Participants Maintaining ≥ 80% of the Body Weight Reduction Achieved in the Parent Trial
Time Frame: Baseline of parent trial to Week 48 of current trial
Baseline of parent trial to Week 48 of current trial

Collaborators and Investigators

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

Sponsor

Amgen

Investigators

  • Study Director: MD, Amgen

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)

July 23, 2026

Primary Completion (Estimated)

December 26, 2027

Study Completion (Estimated)

March 19, 2028

Study Registration Dates

First Submitted

June 29, 2026

First Submitted That Met QC Criteria

June 29, 2026

First Posted (Actual)

July 6, 2026

Study Record Updates

Last Update Posted (Actual)

September 3, 2026

Last Update Submitted That Met QC Criteria

September 2, 2026

Last Verified

September 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 20250197

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

De-identified individual patient data for variables necessary to address the specific research question in an approved data sharing request.

IPD Sharing Time Frame

Data sharing requests relating to this study will be considered beginning 18 months after the study has ended and either 1) the product and indication have been granted marketing authorization in both the US and Europe or 2) clinical development for the product and/or indication discontinues and the data will not be submitted to regulatory authorities. There is no end date for eligibility to submit a data sharing request for this study.

IPD Sharing Access Criteria

Qualified researchers may submit a request containing the research objectives, the Amgen product(s) and Amgen study/studies in scope, endpoints/outcomes of interest, statistical analysis plan, data requirements, publication plan, and qualifications of the researcher(s).In general, Amgen does not grant external requests for individual patient data for the purpose of re-evaluating safety and efficacy issues already addressed in the product labelling. Requests are reviewed by a committee of internal advisors. If not approved, a Data Sharing Independent Review Panel will arbitrate and make the final decision. Upon approval, information necessary to address the research question will be provided under the terms of a data sharing agreement. This may include anonymized individual patient data and/or available supporting documents, containing fragments of analysis code where provided in analysis specifications. Further details are available at the URL below.

IPD Sharing Supporting Information Type

  • STUDY_PROTOCOL
  • SAP
  • ICF
  • CSR

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.

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