A Study of Tirzepatide (LY3298176) Compared With Placebo in Adults With Type 1 Diabetes and Obesity or Overweight
SURPASS-T1D-1
A Phase 3, Multicenter, Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Study Evaluating the Efficacy and Safety of Tirzepatide Once Weekly Compared to Placebo in Adult Participants With Type 1 Diabetes and Obesity or Overweight
3 other identifiers
interventional
905
12 countries
146
Brief Summary
The main purpose of this study is to find out how well and how safely tirzepatide works in adults who have type 1 diabetes and obesity or overweight. Participation in the study will last about 49 weeks.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for phase_3
Started Apr 2025
146 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
April 4, 2025
CompletedFirst Posted
Study publicly available on registry
April 6, 2025
CompletedStudy Start
First participant enrolled
April 25, 2025
CompletedPrimary Completion
Last participant's last visit for primary outcome
November 1, 2026
ExpectedStudy Completion
Last participant's last visit for all outcomes
December 1, 2026
February 17, 2026
February 1, 2026
1.5 years
April 4, 2025
February 13, 2026
Conditions
Outcome Measures
Primary Outcomes (1)
Change from Baseline in Hemoglobin A1c (HbA1c)
Baseline, Week 40
Secondary Outcomes (13)
Percentage of Time Continuous Glucose Monitor (CGM) Glucose Values are Between 70 and 180 milligrams per deciliter (mg/dL) (3.9 and 10.0 millimoles per liter (mmol/L) Inclusive, Per Day
Within 30 days prior to Week 40
Change from Baseline in Body Weight
Baseline, Week 40
Percent Change from Baseline in Body Weight
Baseline, Week 40
Percentage of Participants with ≥5% Body Weight Reduction
Baseline, Week 40
Percentage of Participants with ≥10% Body Weight Reduction
Baseline, Week 40
- +8 more secondary outcomes
Study Arms (5)
Tirzepatide Dose 1
EXPERIMENTALParticipants will receive tirzepatide subcutaneously (SC)
Tirzepatide Dose 2
EXPERIMENTALParticipants will receive tirzepatide SC
Tirzepatide Dose 3
EXPERIMENTALParticipants will receive tirzepatide SC
Tirzepatide Dose 4
EXPERIMENTALParticipants will receive tirzepatide SC
Placebo
PLACEBO COMPARATORParticipants will receive placebo SC
Interventions
Administered SC
Eligibility Criteria
You may qualify if:
- Have type 1 diabetes and on insulin treatment for at least one year prior to screening
- Have an HbA1c value of 7.0% to 10.5% inclusive, at screening
- Have a body mass index (BMI) of ≥25 kilograms per square meter (kg/m2) at screening
- Are of stable weight for at least 90 days prior to screening and agree to not start an intensive diet or exercise program during the study
You may not qualify if:
- Have experienced two or more events requiring hospitalization due to poor glucose control (hyperglycemia or (diabetic ketoacidosis (DKA)) during the period of 180 days prior to screening and until randomization.
- Have experienced one or more events of severe hypoglycemia during the period of 90 days prior to screening and until randomization.
- Are currently receiving or planning to receive treatment for diabetic retinopathy and/or macular edema
- Have had chronic or acute pancreatitis
- Have used any weight loss drugs or alternative remedies, including herbal or nutritional supplements, within 90 days prior to screening
Contact the study team to confirm eligibility.
Sponsors & Collaborators
Study Sites (146)
Sansum Diabetes Research Institute
Santa Barbara, California, 93105, United States
Care Access - Santa Clarita
Santa Clarita, California, 91321, United States
University of Colorado Anschutz Medical Campus
Aurora, Colorado, 80045, United States
Atlanta Diabetes Associates
Atlanta, Georgia, 30318, United States
Orita Clinical Research
Decatur, Georgia, 30034, United States
North Georgia Clinical Research
Woodstock, Georgia, 30189, United States
East-West Medical Research Institute
Honolulu, Hawaii, 96814, United States
Rocky Mountain Clinical Research
Idaho Falls, Idaho, 83404, United States
Southern Illinois University School of Medicine
Springfield, Illinois, 62702, United States
Indiana University Health University Hospital
Indianapolis, Indiana, 46202, United States
Iowa Diabetes and Endocrinology Research Center
West Des Moines, Iowa, 50266, United States
Endocrine and Metabolic Consultants
Rockville, Maryland, 20852, United States
HealthPartners Institute dba International Diabetes Center
Minneapolis, Minnesota, 55416, United States
SKY Integrative Medical Center/SKYCRNG
Ridgeland, Mississippi, 39157, United States
Boeson Research MSO
Missoula, Montana, 59804, United States
Palm Research Center Tenaya
Las Vegas, Nevada, 89128, United States
Palm Research Center Sunset
Las Vegas, Nevada, 89148, United States
Albany Medical College, Division of Community Endocrinology
Albany, New York, 12203, United States
Research Foundation of SUNY - University of Buffalo
Buffalo, New York, 14221, United States
NYC Research
New York, New York, 10016, United States
SUNY Upstate Medical University
Syracuse, New York, 13210, United States
Lucas Research, Inc.
Morehead City, North Carolina, 28557, United States
Care Access - Lima
Lima, Ohio, 45805, United States
Alliance for Multispecialty Research, LLC
Norman, Oklahoma, 73069, United States
Suburban Research Associates
West Chester, Pennsylvania, 19380, United States
Texas Diabetes & Endocrinology, P.A.
Austin, Texas, 78731, United States
Velocity Clinical Research, Dallas
Dallas, Texas, 75230, United States
Tekton Research, LLC.
McKinney, Texas, 75069, United States
Medrasa Clinical Research
Wylie, Texas, 75098, United States
Eastside Research Associates
Redmond, Washington, 98052, United States
Rainier Clinical Research Center
Renton, Washington, 98057, United States
Investigaciones Medicas Imoba Srl
Buenos Aires, C1056ABH, Argentina
Centro de Investigaciones Metabólicas (CINME)
Buenos Aires, C1056ABI, Argentina
CIPREC
Buenos Aires, C1119ACN, Argentina
Consultorio de Investigación Clínica EMO SRL
Buenos Aires, C1405BUB, Argentina
CENUDIAB
Buenos Aires, C1440AAD, Argentina
Instituto de Investigaciones Clínicas Córdoba
Córdoba, 5000, Argentina
Centro Medico Privado San Vicente Diabetes
Córdoba, 5006, Argentina
Centro de Investigaciones Médicas Mar del Plata
Mar del Plata, 7600, Argentina
Instituto Médico Río Cuarto
Río Cuarto, X5800AEV, Argentina
Fundacion Estudios Clinicos
Rosario, 2000, Argentina
Centro de Diagnóstico y Rehabilitación (CEDIR)
Santa Fe, 3000, Argentina
Centro de Salud e Investigaciones Médicas
Santa Rosa, L6300, Argentina
Centro de Diabetes Curitiba
Curitiba, 80810-040, Brazil
Centro De Diabetes Metabolismo E Endocrinologia
Fortaleza, 60175-047, Brazil
Private Practice - Dr.Miguel N. Hissa
Fortaleza, 60430-350, Brazil
Universidade Federal de Goias
Goiânia, 74605-020, Brazil
CPQuali Pesquisa Clínica
São Paulo, 01228-000, Brazil
CPCLIN
São Paulo, 01228-200, Brazil
IBTED - Tecnologia e Educação em Diabetes
São Paulo, 04038-032, Brazil
CEPIC - Centro Paulista de Investigação Clínica
São Paulo, 04266-010, Brazil
Hospital das Clinicas FMUSP
São Paulo, 05403-000, Brazil
CEDOES
Vitória, 29055450, Brazil
Esbjerg sygehus, Syddansk Universitetshospital
Esbjerg, 6700, Denmark
Steno Diabetes Center - Copenhagen
Herlev, 2730, Denmark
Regionshospitalet Gødstrup
Herning, 7400, Denmark
Nordsjællands Hospital - Hillerød
Hillerød, 3400, Denmark
Sjællands Universitetshospital Køge
Køge, 4600, Denmark
Centre Hospitalier Universitaire de Caen - Hôpital Côte de Nacre
Caen, 14033, France
Centre Hospitalier Sud Francilien
Corbeil-Essonnes, 91106, France
Hôtel-Dieu du Creusot - site Harfleur
Le Creusot, 71200, France
Centre du diabète DIAB-eCARE
Lyon, 69008, France
Hôpital Européen Marseille
Marseille, 13003, France
Hôpital de la Conception
Marseille, 13005, France
CHU Montpellier Lapeyronie Hospital
Montpellier, 34295, France
Hôpital Nord Guillaume-et-René-Laennec / CHU de Nantes
Nantes, 44093, France
Hôpital NOVO
Pontoise, 95300, France
CHU Strasbourg-Hautepierre
Strasbourg, 67098, France
Centre Hospitalier intercommunal de Toulon La Seyne sur Mer
Toulon, 83100, France
CHU Rangueil
Toulouse, 31059, France
Groupe Hospitalier Mutualiste Les Portes du Sud
Vénissieux, 69200, France
Diabetespraxis Mergentheim
Bad Mergentheim, 97980, Germany
Diabetes- und Stoffwechselpraxis Bochum
Bochum, 44869, Germany
InnoDiab Forschung Gmbh
Essen, 45136, Germany
Diabetes Zentrum Wilhelmsburg
Hamburg, 21109, Germany
Klinikum Karlsburg
Karlsburg, 17495, Germany
Universitätsklinikum Leipzig
Leipzig, 04103, Germany
Institut für Diabetesforschung GmbH Münster
Münster, 48145, Germany
RED-Institut GmbH
Oldenburg, 23758, Germany
Arztpraxis Christine Kosch Pirna
Pirna, 01796, Germany
Yitzhak Shamir Medical Center
Beer Yaacov, 70300, Israel
Soroka Medical Center
Beersheba, 8410101, Israel
Rambam Health Care Campus
Haifa, 3109601, Israel
Institute of Diabetes, Technology and Research - Clalit Health
Herzliya, 4600201, Israel
Hadassah Medical Center
Jerusalem, 9112001, Israel
Schneider Children's Medical Center
Petah Tikva, 4920235, Israel
Rabin Medical Center
Petah Tikva, 4941492, Israel
Sheba Medical Center
Ramat Gan, 5262100, Israel
Diabetes Medical Center
Tel Aviv, 51549, Israel
Sourasky Medical Center
Tel Aviv, 6423906, Israel
IRCCS - AOU di Bologna
Bologna, 40138, Italy
AOU Renato Dulbecco
Catanzaro, 88100, Italy
Azienda Ospedaliera Universitaria Careggi
Florence, 50134, Italy
Ospedale San Raffaele
Milan, 20132, Italy
University of Naples Federico II
Naples, 80100, Italy
Azienda Ospedale - Università Padova
Padua, 35128, Italy
Fondazione Policlinico Universitario Agostino Gemelli IRCCS - Università Cattolica del Sacro Cuore
Roma, 00168, Italy
Azienda Ospedaliero-Universitaria Città della Salute e della Scienza di Torino
Torino, 10126, Italy
The Institute of Medical Science, Asahi Life Foundation
Chūōku, 103-0002, Japan
Matoba Internal Medicine Clinic
Ebina, 243-0432, Japan
Clinic Masae Minami
Fukuoka, 815-0071, Japan
Japanese Red Cross Fukuoka Hospital
Fukuoka, 815-8555, Japan
Hachioji Diabetes Clinic
Hachioji-shi, 192-0083, Japan
Takai Internal Medicine Clinic
Kamakura-shi, 247-0056, Japan
Shiraiwa Medical Clinic
Kashiwara, 582-0005, Japan
Kasugai Municipal Hospital
Kasugai, 486-8510, Japan
Kimitsu Chuo Hospital
Kisarazu, 292-8535, Japan
Yamanashi Prefectural Central Hospital
Kofu, 400-8506, Japan
Kumamoto Central Hospital - Kumamoto
Kumamoto, 862-0965, Japan
Jinnouchi Hospital
Kumamoto, 862-0976, Japan
Kure Medical Center
Kure, 737-0023, Japan
Mikannohana Clinic, Diabetes, Endocrinology and Metabolism
Matsuyama, 790-0034, Japan
Kozawa Eye Hospital and Diabetes Center
Mito, 310-0845, Japan
Heiwadai Hospital
Miyazaki, 880-0034, Japan
Soleil Chikusa Clinic
Nagoya, 464-0858, Japan
Tosaki Clinic for Diabetes and Endocrinology
Nagoya, 468-0009, Japan
Nakakinen clinic
Naka, 311-0113, Japan
Osaka City General Hospital
Osaka, 534-0021, Japan
Abe Clinic
Ōita, 870-0039, Japan
Odori Diabetes
Sapporo, 060-0001, Japan
Manda Memorial Hospital
Sapporo, 060-0062, Japan
Shimonoseki Medical Center
Shimonoseki, 750-0061, Japan
Tomonaga Clinic
Shinjuku, 160-0022, Japan
Suruga Clinic
Shizuoka, 424-0855, Japan
Tama Center Clinic Mirai
Tama, 206-0033, Japan
Noritake Clinic
Ushiku, 300-1207, Japan
Japanese Red Cross Society - Wakayama Medical Center
Wakayama, 640-8558, Japan
Enclifar Ensayos Clínicos Farmacológicos Sc
Chihuahua City, 31110, Mexico
Unidad de Investigaci�n Cl�nica Cardiometabolica de Occidente
Guadalajara, 44150, Mexico
Centro de Investigacion Medica de Occidente, S.C.
Guadalajara, 44260, Mexico
Unidad de Investigación Clínica y Atención Médica HEPA S.C.
Guadalajara, 44670, Mexico
Invecordis S.C.
Hacienda de Las Palmas, 52763, Mexico
CEINV Salud
Monterrey, 64020, Mexico
Clínica García Flores SC
Monterrey, 64610, Mexico
Consultorio Médico de Endocrinología y Pediatría
Puebla City, 72190, Mexico
Medsal Centro Médico
Tampico, 89210, Mexico
Advanced Clinical Research, LLC
Bayamón, 00959, Puerto Rico
Manati Center for Clinical Research
Manatí, 00674, Puerto Rico
CHUAC-Complejo Hospitalario Universitario A Coruña
A Coruña, 15006, Spain
Hospital Universitari Vall d'Hebron
Barcelona, 08035, Spain
Hospital Clínic de Barcelona
Barcelona, 08036, Spain
Hospital de la Santa Creu i Sant Pau
Barcelona, 08041, Spain
Complejo Hospitalario Universitario de Ferrol (CHUF)- Hospital Naval
Ferrol, 15405, Spain
Hospital Universitario de Móstoles
Móstoles, 28935, Spain
Hospital Universitario Marqués de Valdecilla
Santander, 39008, Spain
Hospital Universitario Virgen Del Rocio
Seville, 41013, Spain
Related Links
MeSH Terms
Conditions
Interventions
Condition Hierarchy (Ancestors)
Intervention Hierarchy (Ancestors)
Study Officials
- STUDY DIRECTOR
Call 1-877-CTLILLY (1-877-285-4559) or 1-317-615-4559 Mon - Fri 8 AM - 8 PM Eastern time (UTC/GMT - 5 hours, EST)
Eli Lilly and Company
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
April 4, 2025
First Posted
April 6, 2025
Study Start
April 25, 2025
Primary Completion (Estimated)
November 1, 2026
Study Completion (Estimated)
December 1, 2026
Last Updated
February 17, 2026
Record last verified: 2026-02
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.