A Study of Tirzepatide (LY3298176) in Participants With Obesity or Overweight
SURMOUNT-1
Efficacy and Safety of Tirzepatide Once Weekly in Participants Without Type 2 Diabetes Who Have Obesity or Are Overweight With Weight- Related Comorbidities: A Randomized, Double-Blind, Placebo-Controlled Trial (SURMOUNT-1)
2 other identifiers
interventional
2,539
10 countries
118
Brief Summary
This is a study of tirzepatide in participants with overweight and obesity. The main purpose is to learn more about how tirzepatide affects body weight. The study has two phases: A main phase and an extension phase. The main phase of the study will last 72 weeks. Participants with prediabetes will continue in the extension for another 2 years.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for phase_3
Started Dec 2019
Longer than P75 for phase_3
118 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
Click on a node to explore related trials.
Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
December 2, 2019
CompletedFirst Posted
Study publicly available on registry
December 3, 2019
CompletedStudy Start
First participant enrolled
December 4, 2019
CompletedPrimary Completion
Last participant's last visit for primary outcome
April 1, 2022
CompletedResults Posted
Study results publicly available
April 24, 2023
CompletedStudy Completion
Last participant's last visit for all outcomes
July 6, 2024
CompletedJuly 24, 2025
July 1, 2025
2.3 years
December 2, 2019
March 30, 2023
July 3, 2025
Conditions
Keywords
Outcome Measures
Primary Outcomes (2)
Percent Change From Baseline in Body Weight (Primary Treatment Period)
Least Squares (LS) Mean was calculated using mixed-model repeated measures (MMRM) with baseline, analysis country, sex, prediabetes status at randomization, treatment, time, treatment\*time (Type III sum of squares) in the model.
Baseline, Week 72
Percentage of Participants Who Achieve ≥5% Body Weight Reduction (Primary Treatment Period)
Percentage of participants who achieve greater than or equal to( ≥) 5% body weight reduction.
Week 72
Secondary Outcomes (24)
Change From Baseline in Body Weight (Pooled Doses of Tirzepatide 10 mg and 15 mg) - Primary Treatment Period
Baseline, Week 20
Percentage of Participants Who Achieve ≥10% Body Weight Reduction (Primary Treatment Period)
Week 72
Percentage of Participants Who Achieve ≥15% Body Weight Reduction (Primary Treatment Period)
Week 72
Percentage of Participants Who Achieve ≥20% Body Weight Reduction (Primary Treatment Period)
Week 72
Change From Baseline in Waist Circumference (Primary Treatment Period)
Baseline, Week 72
- +19 more secondary outcomes
Study Arms (4)
Placebo
PLACEBO COMPARATOR* Primary Treatment Period (Week 0-Week 72): Participants with normoglycemia or prediabetes at the time of randomization received once weekly (QW) subcutaneous (SC) doses of a matching placebo, administered over a period of 72 weeks. * Additional Treatment Period (Week 72-Week 176): At week 72, only participants who had prediabetes at the time of randomization and had completed the primary treatment period continued receiving the placebo dose SC QW until week 176. * Safety Follow-up Period: Participants who had completed or discontinued the primary treatment period were followed for safety for 4 weeks (weeks 72 - week 76), and those who had completed or discontinued the additional treatment period (prediabetes at randomization) were followed for 17 weeks (week 176 - week 193). No treatment was administered during this period.
5 mg Tirzepatide
EXPERIMENTAL* Primary Treatment Period (Week 0-Week 72): Participants with normoglycemia or prediabetes at the time of randomization received QW SC doses of tirzepatide, starting at 2.5 milligrams (mg) and increasing by 2.5 mg every 4 weeks until reaching a dose of 5 mg, which was then maintained up to week 72. * Additional Treatment Period (Week 72-Week 176): At week 72, only participants who had prediabetes at the time of randomization and had completed the primary treatment period continued receiving the 5 mg tirzepatide dose SC QW until week 176. * Safety Follow-up Period: Participants who had completed or discontinued the primary treatment period were followed for safety for 4 weeks (weeks 72 - week 76), and those who had completed or discontinued the additional treatment period (prediabetes at randomization) were followed for 17 weeks (week 176 - week 193). No treatment was administered during this period.
10 mg Tirzepatide
EXPERIMENTAL* Primary Treatment Period (Week 0-Week 72): Participants with normoglycemia or prediabetes at the time of randomization received QW SC doses of tirzepatide, starting at 2.5 mg and increasing by 2.5 mg every 4 weeks until reaching a dose of 10 mg, which was then maintained up to week 72. * Additional Treatment Period (Week 72-Week 176): At week 72, only participants who had prediabetes at the time of randomization and had completed the primary treatment period continued receiving the 10 mg tirzepatide dose SC QW until week 176. * Safety Follow-up Period: Participants who had completed or discontinued the primary treatment period were followed for safety for 4 weeks (weeks 72 - week 76), and those who had completed or discontinued the additional treatment period (prediabetes at randomization) were followed for 17 weeks (week 176 - week 193). No treatment was administered during this period.
15 mg Tirzepatide
EXPERIMENTAL* Primary Treatment Period (Week 0-Week 72): Participants with normoglycemia or prediabetes at the time of randomization received QW SC doses of tirzepatide, starting at 2.5 mg and increasing by 2.5 mg every 4 weeks until reaching a dose of 15 mg, which was then maintained up to week 72. * Additional Treatment Period (Week 72-Week 176): At week 72, only participants who had prediabetes at the time of randomization and had completed the primary treatment period continued receiving the 15 mg tirzepatide dose SC QW until week 176. * Safety Follow-up Period: Participants who had completed or discontinued the primary treatment period were followed for safety for 4 weeks (weeks 72 - week 76), and those who had completed or discontinued the additional treatment period (prediabetes at randomization) were followed for 17 weeks (week 176 - week 193). No treatment was administered during this period.
Interventions
Administered SC
Eligibility Criteria
You may qualify if:
- Body mass Index (BMI) ≥30 kilograms per square meter (kg/m²), or ≥27 kg/m² and previous diagnosis with at least one of the following comorbidities: hypertension, dyslipidemia, obstructive sleep apnea, cardiovascular disease
- History of at least one unsuccessful dietary effort to lose body weight
You may not qualify if:
- Diabetes mellitus
- Change in body weight greater than 5 kg within 3 months prior to starting study
- Obesity induced by other endocrinologic disorders or monogenetic or syndromic forms of obesity
- History of pancreatitis
- Family or personal history of medullary thyroid carcinoma (MTC) or multiple endocrine neoplasia syndrome type 2 (MEN-2)
- History of significant active or unstable major depressive disorder (MDD) or other severe psychiatric disorder within the last 2 years
- Any lifetime history of a suicide attempt
Contact the study team to confirm eligibility.
Sponsors & Collaborators
Study Sites (118)
Cahaba Research
Pelham, Alabama, 35124, United States
Perseverance Research Center
Scottsdale, Arizona, 85224, United States
John Muir Physician Network Clinical Research Center
Concord, California, 94520, United States
Valley Research
Fresno, California, 93720, United States
National Research Institute - Wilshire
Los Angeles, California, 90057, United States
Catalina Research Institute, LLC
Montclair, California, 91763, United States
Encompass Clinical Research
Spring Valley, California, 91978, United States
University Clinical Investigators, Inc.
Tustin, California, 92780, United States
Yale University School of Medicine
New Haven, Connecticut, 06519, United States
Chase Medical Research, LLC
Waterbury, Connecticut, 06708, United States
Suncoast Research Group
Miami, Florida, 33135, United States
New Horizon Research Center
Miami, Florida, 33165, United States
Renstar Medical Research
Ocala, Florida, 34471, United States
Oviedo Medical Research
Oviedo, Florida, 32765, United States
ForCare Clinical Research
Tampa, Florida, 33613, United States
Center for Advanced Research & Education
Gainesville, Georgia, 30501, United States
Herman Clinical Research
Suwanee, Georgia, 30024, United States
SKY Integrative Medical Center/SKYCRNG
Union City, Georgia, 30291, United States
East-West Medical Research Institute
Honolulu, Hawaii, 96814, United States
Midwest Institute for Clinical Research
Indianapolis, Indiana, 46260, United States
Iowa Diabetes and Endocrinology Research Center
West Des Moines, Iowa, 50265, United States
Cotton O'Neil Diabetes & Endocrinology
Topeka, Kansas, 66606, United States
L-MARC Research Center
Louisville, Kentucky, 40213, United States
NECCR PrimaCare Research
Fall River, Massachusetts, 02721, United States
ActivMed Practices and Research
Methuen, Massachusetts, 01844, United States
Arcturus Healthcare , PLC, Troy Internal Medicine Research Division
Troy, Michigan, 48098, United States
StudyMetrix Research
City of Saint Peters, Missouri, 63303, United States
Clinvest Research LLC
Springfield, Missouri, 65807, United States
Palm Research Center Sunset
Las Vegas, Nevada, 89148, United States
Premier Research
Trenton, New Jersey, 08611, United States
NYU Langone Health
New York, New York, 10016, United States
Weill Cornell Medical College
New York, New York, 10021, United States
Rochester Clinical Research, LLC
Rochester, New York, 14609, United States
University of North Carolina Medical Center
Chapel Hill, North Carolina, 27514, United States
PharmQuest
Greensboro, North Carolina, 27408, United States
Lillestol Research
Fargo, North Dakota, 58104, United States
Velocity Clinical Research, Cleveland
Cleveland, Ohio, 44122, United States
Aventiv Research Inc
Columbus, Ohio, 43213, United States
Alliance for Multispecialty Research, LLC
Norman, Oklahoma, 73069, United States
Summit Research Network
Portland, Oregon, 97210, United States
Detweiler Family Medicine & Associates
Lansdale, Pennsylvania, 19446, United States
Preferred Primary Care Physicians
Uniontown, Pennsylvania, 15401, United States
Velocity Clinical Research, Providence
East Greenwich, Rhode Island, 02818, United States
Medical University of South Carolina
Charleston, South Carolina, 29425, United States
Mountain View Clinical Research, Inc.
Greer, South Carolina, 29651, United States
Coastal Carolina Research Center
North Charleston, South Carolina, 29405, United States
WR-Clinsearch, LLC
Chattanooga, Tennessee, 37421, United States
Texas Diabetes & Endocrinology, P.A.
Austin, Texas, 78749, United States
Dallas Diabetes Research Center
Dallas, Texas, 75230, United States
North Texas Endocrine Center
Dallas, Texas, 75231, United States
Research Institute of Dallas
Dallas, Texas, 75231, United States
Southern Endocrinology Associates
Mesquite, Texas, 75149, United States
Texas Diabetes & Endocrinology, P.A.
Round Rock, Texas, 78681, United States
Consano Clinical Research, LLC
Shavano Park, Texas, 78231, United States
Stat Research S.A.
CABA, Buenos Aires, 1023, Argentina
CEDIC
CABA, Buenos Aires, C1060ABN, Argentina
Consultorio de Investigación Clínica EMO SRL
Ciudad Autonoma de Buenos Aires, Buenos Aires, C1405BUB, Argentina
Centro de Investigaciones Metabólicas (CINME)
Ciudad Autónoma de Buenos Aires, Buenos Aires, C1056, Argentina
Instituto de Investigaciones Clínicas Mar del Plata
Mar del Plata, Buenos Aires, 7600, Argentina
DIM Clinica Privada
Ramos Mejía, Buenos Aires, 1704, Argentina
GO Centro Médico San Nicolás
San Nicolás de los Arroyos, Buenos Aires, 2900, Argentina
Centro Médico Viamonte
Buenos Aires, Buenos Aires F.D., C1120AAC, Argentina
Mautalen Salud e Investigación
Buenos Aires, Buenos Aires F.D., C1128AAF, Argentina
CEDOES
Vitória, Espírito Santo, 29055-450, Brazil
Instituto de Pesquisa clinica de Campinas
Campinas, São Paulo, 13060-080, Brazil
Loema - Instituto de Pesquisa Clinica
Campinas, São Paulo, 13092-133, Brazil
Instituto Brasil de Pesquisa Clínica - IBPCLIN
Rio de Janeiro, 22241-180, Brazil
CPQuali Pesquisa Clínica
São Paulo, 01228-000, Brazil
CPCLIN
São Paulo, 01228-200, Brazil
CEPIC - Centro Paulista de Investigação Clínica
São Paulo, 04266-010, Brazil
Hospital da Clinicas da Faculdade de Medicina da USP
São Paulo, 05403-000, Brazil
Beijing Tsinghua Changgung Hospital
Changping, Beijing Municipality, 102202, China
The Fourth Affiliated Hospital of Harbin Medical University
Harbin, Heilongjiang, 150001, China
The Second Affiliated Hospital of Nanjing Medical University
Nanjing, Jiangsu, 210011, China
Jinan Central Hospital
Jinan, Shandong, 250013, China
The First Affiliated Hospital of Xi'an Medical University
Xi’an, Shanxi, 710077, China
West China Hospital, Sichuan University
Chengdu, Sichuan, 610041, China
Ningbo First Hospital
Ningbo, Zhejiang, 315010, China
Gujarat Endocrine Center
Ahmedabad, Gujarat, 380006, India
Sir J.J. Group of Hospitals
Mumbai, Maharashtra, 400008, India
Deenanath Mangeshkar Hospital & Research Centre
Pune, Maharashtra, 411004, India
Care Hospitals Hyderabad- Banjara Hills
Hyderabad, Telangana, 500034, India
ILS Hospital
Kolkata, West Bengal, 700064, India
Fortis Hospital
Delhi, 110088, India
Medical Corporation Heishinkai OCROM Clinic
Suita-shi, Osaka, 565-0853, Japan
Tokyo-Eki Center-building Clinic
Chuo-ku, Tokyo, 103-0027, Japan
Medical Corporation Chiseikai Tokyo Center Clinic
Chuo-ku, Tokyo, 103-0028, Japan
Fukuwa Clinic
Chuo-ku, Tokyo, 104-0031, Japan
AMC Nishiumeda Clinic
Osaka, 530-0001, Japan
Centro de Investigacion en Artritis y Osteoporosis SC
Mexicali, Estado de Baja California, 21200, Mexico
Unidad de Investigacion Clinica y Atencion Medica HEPA
Guadalajara, Jalisco, 44670, Mexico
Virgen Cardiovascular Research S.C
Guadalajara, Jalisco, 44670, Mexico
Centro Especializado En Diabetes, Obesidad Y Prevencion De Enfermedades Cardiovasculares
Mexico City, Mexico City, 11650, Mexico
RM Pharma Specialists
Mexico City, Mexico City, 3100, Mexico
Instituto de Diabetes, Obesidad y Nutricion
Cuernavaca, Morelos, 62250, Mexico
Hospital Universitario "Dr. Jose Eleuterio Gonzalez"
Monterrey, Nuevo León, 66460, Mexico
Centro Para El Desarrollo de La Medicina Y de Asistencia Medica Especializada S.C.
Culiacán, Sinaloa, 80230, Mexico
Investigacion en Salud y Metabolismo S.C
Chihuahua City, 31217, Mexico
Arké SMO S.A de C.V
Veracruz, 91910, Mexico
Manati Center for Clinical Research
Manatí, 00674, Puerto Rico
Ponce Medical School Foundation Inc.
Ponce, 00716, Puerto Rico
Latin Clinical Trial Center
San Juan, 00909, Puerto Rico
GCM Medical Group, PSC- Hato Rey Site
San Juan, 00917, Puerto Rico
Private Practice - Dr. Luis Rivera Colon
San Juan, 00921, Puerto Rico
Ivanovo Regional Healthcare Institution Cardiology Dispensary
Ivanovo, Ivanovo Oblast, 153012, Russia
Immanuel Kant Baltic Federal University
Kaliningrad, Kaliningrad Oblast, 236041, Russia
Endocrinology Research Center of Rosmedtechnologies
Moscow, Moscow, 117036, Russia
Pirogov Russian National Research Medical University
Moscow, Moscow, 117997, Russia
Russian Cardiology Research and Production Complex
Moscow, Moscow, 121552, Russia
State Research Center for Preventive Medicine
Moscow, Moscow, 127051, Russia
Research Institute of Therapy and Preventive Medicine
Novosibirsk, Novosibirsk Oblast, 630089, Russia
St Petersburg SBHI City Hospital No. 38 Named After Semashko
Saint Petersburg, Sankt-Peterburg, 196601, Russia
Izhevsk City Clinical Hospital Number 9
Izhevsk, Udmurtiya Republic, 426063, Russia
Chi-Mei Medical Center
Tainan, Tainan, 71004, Taiwan
National Taiwan University Hospital
Taipei City, Taipei, 10002, Taiwan
Chung Shan Medical University Hospital
Taichung, 402, Taiwan
China Medical University Hospital
Taichung, 40447, Taiwan
National Cheng Kung University Hospital
Tainan, 704, Taiwan
Related Publications (13)
Ishigaki Y, Yamada M, Shingaki T, Oura T, Shimomura I. Efficacy and Safety of Tirzepatide in Japanese Participants With Obesity: A Subpopulation Analysis of the SURMOUNT-1 Trial. Obesity (Silver Spring). 2026 Jan 30. doi: 10.1002/oby.70131. Online ahead of print.
PMID: 41612966DERIVEDWadden TA, Oquendo MA, Kushner RF, Cao D, Karanikas CA, Kechter A, Murphy MA. Psychiatric Safety of Tirzepatide in People With Obesity and No Known Major Psychopathology: A Post Hoc Analysis of SURMOUNT. Obesity (Silver Spring). 2026 Jan 15. doi: 10.1002/oby.70122. Online ahead of print.
PMID: 41537305DERIVEDLi X, Cao D, Sapin H, Wang F, Hunter Gibble T, Raibulet NK, Denning M, Kaplan LM. People With Lowest Physical Functioning Scores Showed Greatest Improvement After Tirzepatide Treatment. Obesity (Silver Spring). 2026 Jan;34(1):114-126. doi: 10.1002/oby.70067. Epub 2025 Nov 4.
PMID: 41187013DERIVEDGourgari E, Srivastava G, Kelly AS, Mojdami D, Cao D, Murphy MA, Karanikas CA, Lee CJ. Early-Onset Obesity and Tirzepatide Treatment: A Post Hoc Analysis of the SURMOUNT Clinical Trials. Obesity (Silver Spring). 2025 Sep;33(9):1668-1679. doi: 10.1002/oby.24348. Epub 2025 Jul 27.
PMID: 40717199DERIVEDArd J, Lee CJ, Gudzune K, Addison B, Lingvay I, Cao D, Mast CJ, Stefanski A, Falcon B, Mojdami D. Weight reduction over time in tirzepatide-treated participants by early weight loss response: Post hoc analysis in SURMOUNT-1. Diabetes Obes Metab. 2025 Sep;27(9):5064-5071. doi: 10.1111/dom.16554. Epub 2025 Jul 17.
PMID: 40677091DERIVEDLinetzky B, Sattar N, Verma S, Krumholz HM, Xie CC, Hoffmann HT, Zimner-Rapuch S, Torcello-Gomez A, Stefanski A. Improvements in Cardiometabolic Risk Factors by Weight Reduction: A Post Hoc Analysis of Adults With Obesity Randomly Assigned to Tirzepatide. Ann Intern Med. 2025 Aug;178(8):1095-1105. doi: 10.7326/ANNALS-24-02623. Epub 2025 Jun 24.
PMID: 40550133DERIVEDHeerspink HJL, Friedman AN, Bjornstad P, van Raalte DH, Cherney D, Cao D, Garcia-Perez LE, Stefanski A, Turfanda I, Bunck MC, Benabbad I, Griffin R, Piras de Oliveira C. Kidney Parameters with Tirzepatide in Obesity with or without Type 2 Diabetes. J Am Soc Nephrol. 2025 Nov 1;36(11):2190-2200. doi: 10.1681/ASN.0000000764. Epub 2025 Jun 13.
PMID: 40512543DERIVEDHorn DB, Kahan S, Batterham RL, Cao D, Lee CJ, Murphy M, Gonsahn-Bollie S, Chigutsa F, Stefanski A, Dunn JP. Time to weight plateau with tirzepatide treatment in the SURMOUNT-1 and SURMOUNT-4 clinical trials. Clin Obes. 2025 Jun;15(3):e12734. doi: 10.1111/cob.12734. Epub 2025 Jan 12.
PMID: 39800653DERIVEDJastreboff AM, le Roux CW, Stefanski A, Aronne LJ, Halpern B, Wharton S, Wilding JPH, Perreault L, Zhang S, Battula R, Bunck MC, Ahmad NN, Jouravskaya I; SURMOUNT-1 Investigators. Tirzepatide for Obesity Treatment and Diabetes Prevention. N Engl J Med. 2025 Mar 6;392(10):958-971. doi: 10.1056/NEJMoa2410819. Epub 2024 Nov 13.
PMID: 39536238DERIVEDGudzune KA, Stefanski A, Cao D, Mojdami D, Wang F, Ahmad N, Ling Poon J. Association between weight reduction achieved with tirzepatide and quality of life in adults with obesity: Results from the SURMOUNT-1 study. Diabetes Obes Metab. 2025 Feb;27(2):539-550. doi: 10.1111/dom.16046. Epub 2024 Nov 4.
PMID: 39497468DERIVEDKrumholz HM, de Lemos JA, Sattar N, Linetzky B, Sharma P, Mast CJ, Ahmad NN, Bunck MC, Stefanski A. Tirzepatide and blood pressure reduction: stratified analyses of the SURMOUNT-1 randomised controlled trial. Heart. 2024 Sep 16;110(19):1165-1171. doi: 10.1136/heartjnl-2024-324170.
PMID: 39084707DERIVEDHankosky ER, Wang H, Neff LM, Kan H, Wang F, Ahmad NN, Stefanski A, Garvey WT. Tirzepatide reduces the predicted risk of developing type 2 diabetes in people with obesity or overweight: Post hoc analysis of the SURMOUNT-1 trial. Diabetes Obes Metab. 2023 Dec;25(12):3748-3756. doi: 10.1111/dom.15269. Epub 2023 Sep 12.
PMID: 37700443DERIVEDJastreboff AM, Aronne LJ, Ahmad NN, Wharton S, Connery L, Alves B, Kiyosue A, Zhang S, Liu B, Bunck MC, Stefanski A; SURMOUNT-1 Investigators. Tirzepatide Once Weekly for the Treatment of Obesity. N Engl J Med. 2022 Jul 21;387(3):205-216. doi: 10.1056/NEJMoa2206038. Epub 2022 Jun 4.
PMID: 35658024DERIVED
Related Links
MeSH Terms
Conditions
Interventions
Condition Hierarchy (Ancestors)
Intervention Hierarchy (Ancestors)
Results Point of Contact
- Title
- Chief Medical Officer
- Organization
- Eli Lilly and Company
Study Officials
- STUDY DIRECTOR
Call 1-877-CTLILLY (1-877-285-4559) or 1-317-615-4559 Mon - Fri 9 AM - 5 PM Eastern time (UTC/GMT - 5 hours, EST)
Eli Lilly and Company
Publication Agreements
- PI is Sponsor Employee
- No
- Restriction Type
- GT60
- Restrictive Agreement
- Yes
Study Design
- Study Type
- interventional
- Phase
- phase 3
- Allocation
- RANDOMIZED
- Masking
- DOUBLE
- Who Masked
- PARTICIPANT, INVESTIGATOR
- Purpose
- TREATMENT
- Intervention Model
- PARALLEL
- Sponsor Type
- INDUSTRY
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
December 2, 2019
First Posted
December 3, 2019
Study Start
December 4, 2019
Primary Completion
April 1, 2022
Study Completion
July 6, 2024
Last Updated
July 24, 2025
Results First Posted
April 24, 2023
Record last verified: 2025-07
Data Sharing
- IPD Sharing
- Will share
- Shared Documents
- STUDY PROTOCOL, SAP, CSR
- Time Frame
- Data are available 6 months after the primary publication and approval of the indication studied in the US and EU, whichever is later. Data will be indefinitely available for requesting.
- Access Criteria
- A research proposal must be approved by an independent review panel and researchers must sign a data sharing agreement.
Anonymized individual patient level data will be provided in a secure access environment upon approval of a research proposal and a signed data sharing agreement.