SURPASS-SWITCH

CompletedPhase 4Results posted

A Study of Tirzepatide (LY3298176) in Adult Participants With Type 2 Diabetes Switching From Dulaglutide (SURPASS-SWITCH)

A Phase 4, Randomized, Open-Label, Active-Controlled Study to Investigate the Efficacy and Safety of Switching From Weekly Dulaglutide to Weekly Tirzepatide in Adults With Type 2 Diabetes

Lead sponsor

Eli Lilly and Company

Assets

Dulaglutide / Tirzepatide

Listed sites

Recruiting sites

—

Enrollment

282

actual

Study population

Obesity / overweight, Type 2 diabetes

Key I/E criteria

•BMI ≥25•HbA1c ≥7%

Primary endpoint

•HbA1c, change

Footprint

Where this trial recruits

Site locations as reported to ClinicalTrials.gov. Site count is not enrollment count; per-site enrollment is not available from source.

Identifiers

Registered as

NCT IDNCT05564039

Org study ID18395

Secondary ID2022-500101-41-00EU Trial Number

Secondary IDI8F-MC-GPIHEli Lilly and Company

Timeline

Milestones

Study first posted2022-10-03actual

Study start2022-11-30actual

Primary completion2024-07-15actual

Study completion2024-08-12actual

Last update posted2025-08-03actual

Results first posted2025-08-03actual

Assets

Investigational agents

Dulaglutide Tirzepatide

Study populations

Who this study enrolls

Obesity / overweightType 2 diabetes

Eligibility

Who can enroll

Minimum age18 Years

SexAll

Healthy volunteersNot accepted

Inclusion criteria

•Have type 2 diabetes

•Have HbA1c ≥7.0% (≥53 mmol/mol) to ≤9.5% (≤80 mmol/mol)

•Are currently on a stable dose of dulaglutide weekly (0.75 mg or 1.5 mg) for at least 6 months prior to screening.

•No treatment with oral antihyperglycemic medication (OAM), or on a stable dose of up to 3 OAMs, which may include metformin, sodium glucose cotransporter-2 inhibitors (SGLT-2i), and/or sulfonylurea, for at least 3 months before screening.

•Have had stable body weight (±5%) during the 90 days preceding screening

•Have BMI ≥25 kilogram/square meter (kg/m²)

Exclusion criteria

•Have type 1 diabetes

•Have a history of chronic or acute pancreatitis

•Have a history of

–proliferative diabetic retinopathy, or

–diabetic maculopathy, or

–nonproliferative diabetic retinopathy that requires acute treatment.

•Have any of these cardiovascular (CV) conditions within 60 days prior to screening:

–acute myocardial infarction,

–cerebrovascular accident (stroke), or

–hospitalization due to congestive heart failure (CHF).

•Have New York Heart Assocation (NYHA) Functional Classification Class IV CHF

•Have family or personal history of medullary thyroid carcinoma (MTC) or multiple endocrine neoplasia syndrome type 2 (MEN2).

•Have within 90 days prior to screening received treatment with medications intended to promote weight loss. This includes prescribed, over-the-counter, or alternative remedies

•Have an estimated glomerular filtration rate (eGFR) <30 mL/minute/1.73 m2 (or lower than the country-specific threshold for discontinuing metformin therapy per local label)

•Have been treated with insulin prior to screening

–Exception: use of insulin for gestational diabetes or short-term use (<14 days) for acute conditions such as acute illness, hospitalization, or elective surgery.

•Have a history of reduction of dose of dulaglutide, due to intolerability, without successful reescalation

Endpoints (26)

What's being measured

Protocol endpoints and posted registry outcome measures, grouped into outcome categories. Composite endpoints show their component event types. Standard codes (LOINC, SNOMED CT) are shown where available.

Coverage by outcome category

Weight & body composition

Glycemic / diabetes

Patient-reported / QoL

Weight & body composition

12 endpoints

Secondary/registry result

Change From Baseline in Body Weight

Time frame:Baseline, Week 40

Body weight, absolute change (kg)

change from baseline, improvement

Posted result

Group	Value (least_squares_mean), kilograms (kg)	95% CI
15 mg Tirzepatide or MTD	-11.0	—
4.5 mg Dulaglutide or MTD	-3.6	—

LS Mean difference (Final Values)-7.495% CI-8.7 – -6.0p<.0001Mixed Models Analysis

Secondary/registry result

Percentage of Participants Who Achieve Weight Loss From Baseline of ≥5%

Time frame:Week 40

≥5% weight-loss responders

threshold achievement, improvement

Posted result

Group	Value (number), percentage of participants	95% CI
15 mg Tirzepatide or MTD	84.33	—
4.5 mg Dulaglutide or MTD	37.40	—

Odds Ratio (OR)9.3195% CI5.11 – 16.98p<0.0001Regression, Logistic

Secondary/registry result

Percentage of Participants Who Achieve Weight Loss From Baseline of ≥10%

Time frame:Week 40

≥10% weight-loss responders

threshold achievement, improvement

Posted result

Group	Value (number), percentage of participants	95% CI
15 mg Tirzepatide or MTD	58.21	—
4.5 mg Dulaglutide or MTD	6.87	—

Odds Ratio (OR)19.3595% CI9.07 – 41.30p<0.0001Regression, Logistic

Secondary/registry result

Percentage of Participants Who Achieve Weight Loss From Baseline of ≥15%

Time frame:Week 40

≥15% weight-loss responders

threshold achievement, improvement

Posted result

Group	Value (number), percentage of participants	95% CI
15 mg Tirzepatide or MTD	27.61	—
4.5 mg Dulaglutide or MTD	0.76	—

Odds Ratio (OR)35.8395% CI7.18 – 178.89p<0.0001Regression, Logistic

Secondary/registry result

Change From Baseline in Waist Circumference

Time frame:Baseline, Week 40

Waist circumference, change

change from baseline, improvement

Posted result

Group	Value (least_squares_mean), centimeter (cm)	95% CI
15 mg Tirzepatide or MTD	-8.2	—
4.5 mg Dulaglutide or MTD	-3.1	—

LS Mean difference (Final Values)-5.195% CI-7.8 – -2.5p0.0002Mixed Models Analysis

Secondary/registry result

Change From Baseline in Body Mass Index (BMI)

Time frame:Baseline, Week 40

BMI, change

change from baseline, improvement

Posted result

Group	Value (least_squares_mean), Kilogram per square meter (kg/m^2)	95% CI
15 mg Tirzepatide or MTD	-3.9	—
4.5 mg Dulaglutide or MTD	-1.3	—

LS Mean difference (Final Values)-2.695% CI-3.1 – -2.1p<0.0001Mixed Models Analysis

Secondary/protocol endpoint

Change From Baseline in Body Weight

Time frame:Baseline, Week 40

Body weight, absolute change (kg)

change from baseline, improvement

Secondary/protocol endpoint

Percentage of Participants Who Achieve Weight Loss From Baseline of ≥5%

Time frame:Week 40

≥5% weight-loss responders

threshold achievement, improvement

Secondary/protocol endpoint

Percentage of Participants Who Achieve Weight Loss From Baseline of ≥10%

Time frame:Week 40

≥10% weight-loss responders

threshold achievement, improvement

Secondary/protocol endpoint

Percentage of Participants Who Achieve Weight Loss From Baseline of ≥15%

Time frame:Week 40

≥15% weight-loss responders

threshold achievement, improvement

Secondary/protocol endpoint

Change From Baseline in Waist Circumference

Time frame:Baseline, Week 40

Waist circumference, change

change from baseline, improvement

Secondary/protocol endpoint

Change From Baseline in Body Mass Index (BMI)

Time frame:Baseline, Week 40

BMI, change

change from baseline, improvement

Glycemic / diabetes

12 endpoints

Primary/registry result

Change From Baseline in HbA1c

Time frame:Baseline, Week 40

HbA1c, change

change from baseline, improvement

LOINC 4548-4

Posted result

Group	Value (least_squares_mean), percentage of HbA1c	95% CI
15 mg Tirzepatide or MTD	-1.59	—
4.5 mg Dulaglutide or MTD	-0.69	—

LS Mean difference (Final Values)-0.9095% CI-1.10 – -0.69p<0.0001Mixed Models Analysis

Primary/protocol endpoint

Change From Baseline in HbA1c

Time frame:Baseline, Week 40

HbA1c, change

change from baseline, improvement

LOINC 4548-4

Secondary/registry result

Percentage of Participants Who Achieved HbA1c <7%

Time frame:Week 40

HbA1c <7.0% achievement

threshold achievement, improvement

LOINC 4548-4

Posted result

Group	Value (number), percentage of participants	95% CI
15 mg Tirzepatide or MTD	84.21	—
4.5 mg Dulaglutide or MTD	52.38	—

Odds Ratio (OR)7.1395% CI3.82 – 13.32p<0.0001Regression, Logistic

Secondary/registry result

Percentage of Participants Who Achieved HbA1c <=6.5%

Time frame:Week 40

HbA1c <6.5% achievement

threshold achievement, improvement

LOINC 4548-4

Posted result

Group	Value (number), percentage of participants	95% CI
15 mg Tirzepatide or MTD	73.88	—
4.5 mg Dulaglutide or MTD	22.73	—

Odds Ratio (OR)12.2495% CI6.51 – 23.02p<0.0001Regression, Logistic

Secondary/registry result

Percentage of Participants Who Achieved HbA1c <5.7%

Time frame:Week 40

HbA1c <5.7% achievement

threshold achievement, improvement

LOINC 4548-4

Posted result

Group	Value (number), percentage of participants	95% CI
15 mg Tirzepatide or MTD	21.64	—
4.5 mg Dulaglutide or MTD	2.27	—

Odds Ratio (OR)15.3495% CI4.58 – 51.36p<0.0001Regression, Logistic

Secondary/registry result

Percentage of Participants Who Achieved Composite Endpoint (HbA1c <=6.5% & Weight Loss >=10% & No-Hypoglycemia)

Time frame:Week 40

threshold achievement, improvement

componentsHbA1c <6.5% achievement, ≥10% weight-loss responders, Documented hypoglycemia, Severe hypoglycemia

Posted result

Group	Value (number), percentage of participants	95% CI
15 mg Tirzepatide or MTD	46.62	—
4.5 mg Dulaglutide or MTD	4.58	—

Odds Ratio (OR)20.4495% CI8.40 – 49.77p<0.0001Regression, Logistic

Secondary/registry result

Change From Baseline in Fasting Serum Glucose (FSG)

Time frame:Baseline, Week 40

Fasting glucose, change

change from baseline, improvement

LOINC 1558-6

Posted result

Group	Value (least_squares_mean), millimole per liter (mmol/L)	95% CI
15 mg Tirzepatide or MTD	-2.00	—
4.5 mg Dulaglutide or MTD	-1.10	—

LS Mean difference (Final Values)-0.9095% CI-1.32 – -0.49p<0.001ANCOVA

Secondary/protocol endpoint

Percentage of Participants Who Achieved HbA1c <7%

Time frame:Week 40

HbA1c <7.0% achievement

threshold achievement, improvement

LOINC 4548-4

Secondary/protocol endpoint

Percentage of Participants Who Achieved HbA1c <=6.5%

Time frame:Week 40

HbA1c <6.5% achievement

threshold achievement, improvement

LOINC 4548-4

Secondary/protocol endpoint

Percentage of Participants Who Achieved HbA1c <5.7%

Time frame:Week 40

HbA1c <5.7% achievement

threshold achievement, improvement

LOINC 4548-4

Secondary/protocol endpoint

Percentage of Participants Who Achieved Composite Endpoint (HbA1c <=6.5% & Weight Loss >=10% & No-Hypoglycemia)

Time frame:Week 40

threshold achievement, improvement

componentsHbA1c <6.5% achievement, ≥10% weight-loss responders, Documented hypoglycemia, Severe hypoglycemia

Secondary/protocol endpoint

Change From Baseline in Fasting Serum Glucose (FSG)

Time frame:Baseline, Week 40

Fasting glucose, change

change from baseline, improvement

LOINC 1558-6

Patient-reported / QoL

2 endpoints

Secondary/registry result

Change From Baseline in Impact of Weight on Quality of Life-Lite Clinical Trials Version (IWQOL-Lite CT) - Physical Functioning Score

Time frame:Baseline, Week 40

IWQOL-Lite physical

change from baseline, improvement

Posted result

Group	Value (least_squares_mean), score on a scale	95% CI
15 mg Tirzepatide or MTD	11.8	—
4.5 mg Dulaglutide or MTD	7.8	—

LS Mean difference (Final Values)4.195% CI-1.0 – 9.2p0.1181ANCOVA

Secondary/protocol endpoint

Change From Baseline in Impact of Weight on Quality of Life-Lite Clinical Trials Version (IWQOL-Lite CT) - Physical Functioning Score

Time frame:Baseline, Week 40

IWQOL-Lite physical

change from baseline, improvement

Publications (2)

Bibliography

Records linked to this trial through ClinicalTrials.gov references, PubMed NCT search, and curated study seeds. 'Canonical' marks design/result papers; others are registry references or candidates.

Registry references + supporting bibliography

Safety and efficacy of switching from dulaglutide to tirzepatide across clinically relevant baseline characteristics in participants with T2D: subgroup analysis of SURPASS-SWITCH.
BMJ open diabetes research & care2026 Mar 30PMID41912265doi:10.1136/bmjdrc-2025-005711via clinicaltrials gov reference derived + pubmed nct search
Comparison of Dose Escalation Versus Switching to Tirzepatide Among People With Type 2 Diabetes Inadequately Controlled on Lower Doses of Dulaglutide : A Randomized Clinical Trial.
Annals of internal medicine2025 May (month)PMID40183678doi:10.7326/ANNALS-24-03849via clinicaltrials gov reference derived + pubmed nct search

Provenance

Sources

Trial identity, design, statusClinicalTrials.gov API v2

Snapshot dateJuly 1, 2026

Endpoint classificationDelfa endpoint taxonomy v2 (May 13, 2026)

Results tableClinicalTrials.gov results section

Trial facts come from public ClinicalTrials.gov records. Endpoint categories are Delfa's classification of those records, not a ClinicalTrials.gov field. All figures reflect the July 1, 2026 snapshot.