CompletedPhase 3Results posted

Antidiabetic Effects of Adding a DPP-4 Inhibitor to Pre-Existing Treatment With an Incretin Mimetic in Patients With T2D

Antidiabetic Effects of Adding a DPP-4 Inhibitor (Sitagliptin) to Pre-Existing Treatment With an Incretin Mimetic (Liraglutide) in Patients With Type 2 Diabetes Treated With Metformin

Lead sponsor

Michael A. Nauck

Asset

Liraglutide

Subcutaneous · GLP-1 agonist

Listed sites

Recruiting sites

Actual enrollment

Study population

Type 2 diabetes

Eligibility highlights

•BMI 22-40•HbA1c 6.5-8.5%

Primary endpoint

•Postprandial glucose

Registered trial locations

Locations reported to ClinicalTrials.gov for this trial snapshot. Site count is not enrollment count; per-site enrollment is not available from source.

Identifiers

Registered as

NCT IDNCT01937598

Org study ID120-0569-DZBL-2012

Secondary ID2013-001764-35

Timeline

Milestones

Study first posted2013-09-09estimated

Last update posted2017-01-30estimated

Results first posted2017-01-30estimated

Study start2013-08 (month precision)

Primary completion2014-04actual (month precision)

Study completion2015-06actual (month precision)

Assets

Investigational agents

Liraglutide

Who this study enrolls

Type 2 diabetes

Who can enroll

Minimum age25 Years

Maximum age75 Years

SexAll

Healthy volunteersNot accepted

Inclusion criteria

•Signed \& dated written informed consent

•Male \& female subjects with a diagnosis of type 2 diabetes mellitus according to ADA criteria at least 4 months prior to screening

•Medical history without major pathology (with the exception of type 2 diabetes) as judged by the investigator

•On a stable regimen of metformin for at least 1 month and liraglutide 1.2 mg for at least 1 week at the time-point of randomisation.

•Age: 25 - 75 years, both inclusive

•Body mass index (BMI): 22 - 40kg/m^2, both inclusive

•HbA1c ≥ 6.5 and ≤ 8.5% (≥ 7.0 and ≤ 8.5% for patients without previous liraglutide treatment)

•Female must be post-menopausal, surgically sterilized or practicing an effective birth control

Exclusion criteria

•Subjects with type 1 diabetes, maturity onset diabetes of the young (MODY) or secondary forms of diabetes such as due to pancreatitis

•Current or previous treatment with insulin therapy (except for treatment at diabetes' diagnosis, within a clinical trial, for surgical procedures or during an acute illness, and no insulin administration within the 6 months before screening)

•Treatment with any hypoglycaemic medication other than metformin and liraglutide within one month prior to screening

•Known of diabetic gastroparesis and / or prokinetic therapy

•Subjects that underwent surgery of the upper gastrointestinal tract

•Women who are pregnant, intending to become pregnant during the study period, currently lactating females, or women of child-bearing potential not using highly effective, medically approved birth control methods

•Any severe medical or surgical history of conditions likely to confound study assessments or study endpoints, for example but not limited to haemoglobinopathies, inflammatory bowel disease, cystic fibrosis, bariatric surgery and/or any surgery shortening the intestine, history of lactose intolerance, lactose- or glucose-galactose-malabsorption

•A suspicion of medullary thyroid cancer or a multiple endocrine neoplasia

•A personal or family history of medullar thyroid cancer or a multiple endocrine neoplasia

•Serious and/or unstable coronary heart disease (unstable angina, myocardial infarction within the preceding 6 months), congestive heart failure of New York Heart Association Class III or worse (severe limitation of physical activity; physical activity of low intensity resulting in fatigue, palpitation, or dyspnoea), second/third degree heart block, superior vena cava syndrome, uncontrolled hypertension, history of congenital QT-syndrome within family, history of stroke (within the preceding 6 months) or serious peripheral vascular disease

•History of arrhythmia (multifocal premature ventricular contractions, bigeminy, trigeminy, ventricular tachycardia, or uncontrolled atrial fibrillation) that is symptomatic or requires treatment (grade 3), left bundle branch block, or asymptomatic sustained ventricular tachycardia are not allowed

•Marked diabetic complications: severe autonomic or sensory neuropathy including previously diagnosed gastroparesis; proliferative retinopathy

•Any respiratory disease leading to respiratory insufficiency and/or depression including but not limited to clinically significant: bronchial asthma, chronic obstructive pulmonary disease, that might impact to the breath test, as judged by the investigator

•Clinically significant vital signs including known bradycardia with pulse rate < 50/min or 12-lead ECG findings including QTc (corrected QT interval) > 450 msec for males or QTc > 470 msec for women

•Clinically significant abnormal haematology, biochemistry, lipids, or urinalysis or coagulation screening tests, as judged by the Investigator

•Moderate or severe renal dysfunction defined as an estimated creatinine clearance (MDRD equation) GFR (glomerular filtration rate) <50 ml/min.

•Clinical or laboratory evidence of hepatic dysfunction or disease; laboratory evidence defined as any of the following parameters: alkaline phosphatase, ALT , AST or bilirubin > 3x ULN (upper Limit of normal). Isolated mild rise in bilirubin considered to be due to Gilbert's condition is allowed

•Uncontrolled high blood pressure (DBP (diastolic blood pressure) > 95 mmHg and/or SBP (systolic blood pressure) > 160 mmHg), unless clearly documented to be white-coat hypertension

•History of any psychiatric condition that might impair the subject's ability to understand or to comply with the requirements of the study or to provide informed consent

•History of relevant drug and/or food allergies or a history of severe anaphylactic reaction

•Currently active or history of alcohol abuse (defined as an intake of more than 24 units of alcohol per week; one unit of alcohol equals approximately 250 mL of beer, 100 mL of wine or 35 mL of spirits) or drug addiction (including soft drugs like cannabis products)

•Use of concomitant medication which would be likely to interact with metformin, sitagliptin or liraglutide (according to the subject information leaflet). Participation in another study within the 3 months preceding screening or 5-half-lives of drug studied, whichever is longer, prior to study drug administration

•Malignancy within 5 years of study start, except for successfully treated local basal cell carcinomas

•Known to be positive for Hepatitis B surface antigen or Hepatitis C antibodies (or diagnosed with active hepatitis according to local practice)

•Subject who has donated or lost > 500 mL blood within 3 months prior to screening \& has a Hb < 14 g/dl at screening

•History of hypersensitivity to the study drug or any of the excipients or to medicinal products with similar chemical structures

•Veins unsuitable for repeated venipuncture

Endpoints (18)

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

Glycemic / diabetes

Safety / tolerability / PK

Cardiometabolic biomarkers

Other (unclassified)

Glycemic / diabetes

10 endpoints

Primary/registry result

Incremental Area Under the Plasma Glucose (BG) Concentration-time Profile (AUC)

Time frame:0 to 300 min post mixed meal test

Postprandial glucose

concentration, improvement

Posted result

Group	Mean · [mg*min/dL]	95% CI
Sitagliptin	5678	-
Placebo	5557	-

Primary/protocol endpoint

Incremental Area Under the Plasma Glucose (BG) Concentration-time Profile (AUC)

Time frame:0 to 300 min post mixed meal test

Postprandial glucose

concentration, improvement

Secondary/registry result

AUC Plasma Glucose

Time frame:Approximately 6 weeks (range 9 - 60 days / 8.5 weeks)

Postprandial glucose

descriptive, improvement

Posted result

Group	Mean · mmol/l*min	95% CI
Sitagliptin	315.4	-
Placebo	308.7	-

Secondary/registry result/low confidence

AUC Insulin

Time frame:Approximately 6 weeks (range 9 - 60 days / 8.5 weeks)

descriptive

Posted result

Group	Mean · nmol/l*min	95% CI
Sitagliptin	45.8	-
Placebo	42.6	-

Secondary/registry result

AUC C-peptide

Time frame:Approximately 6 weeks (range 9 - 60 days / 8.5 weeks)

C-peptide AUC

concentration, descriptive

Posted result

Group	Mean · nmol/l*min	95% CI
Sitagliptin	171.5	-
Placebo	159.2	-

Secondary/registry result

AUC Glucagon

Time frame:Approximately 6 weeks (range 9 - 60 days / 8.5 weeks)

AUC glucagon

concentration, improvement

Posted result

Group	Mean · pmol/l*min	95% CI
Sitagliptin	6933	-
Placebo	7004	-

Secondary/protocol endpoint

AUC Plasma Glucose

Time frame:Approximately 6 weeks (range 9 - 60 days / 8.5 weeks)

Postprandial glucose

descriptive, improvement

Secondary/protocol endpoint

AUC Insulin

Time frame:Approximately 6 weeks (range 9 - 60 days / 8.5 weeks)

concentration, descriptive

Secondary/protocol endpoint

AUC C-peptide

Time frame:Approximately 6 weeks (range 9 - 60 days / 8.5 weeks)

C-peptide AUC

change from baseline, improvement

Secondary/protocol endpoint/low confidence

AUC Glucagon

Time frame:Approximately 6 weeks (range 9 - 60 days / 8.5 weeks)

concentration, descriptive

Cardiometabolic biomarkers

2 endpoints

Secondary/registry result

AUC Total GIP

Time frame:Approximately 6 weeks (range 9 - 60 days / 8.5 weeks)

AUC GIP total

concentration, descriptive

Posted result

Group	Mean · pmol/l*min	95% CI
Sitagliptin	6242	-
Placebo	7523	-

Secondary/registry result

AUC Active GIP

Time frame:Approximately 6 weeks (range 9 - 60 days / 8.5 weeks)

AUC active GIP

concentration, descriptive

Posted result

Group	Mean · pmol/l*min	95% CI
Sitagliptin	6270	-
Placebo	3496	-

Safety / tolerability / PK

5 endpoints

Secondary/registry result

AUC Total GLP-1

Time frame:Approximately 6 weeks (range 9 - 60 days / 8.5 weeks)

concentration, descriptive

Posted result

Group	Mean · pmol/l*min	95% CI
Sitagliptin	748	-
Placebo	1143	-

Secondary/registry result

AUC Active GLP-1

Time frame:Approximately 6 weeks (range 9 - 60 days / 8.5 weeks)

concentration, descriptive

Posted result

Group	Mean · pmol/l*min	95% CI
Sitagliptin	607.9	-
Placebo	418.4	-

Secondary/protocol endpoint

AUC Total GLP-1

Time frame:Approximately 6 weeks (range 9 - 60 days / 8.5 weeks)

AUC₀-∞

concentration, descriptive

Secondary/protocol endpoint

AUC Active GLP-1

Time frame:Approximately 6 weeks (range 9 - 60 days / 8.5 weeks)

AUC₀-∞

concentration, descriptive

Secondary/protocol endpoint/low confidence

AUC Active GIP

Time frame:Approximately 6 weeks (range 9 - 60 days / 8.5 weeks)

concentration, descriptive

Other (unclassified)

1 endpoint

Secondary/protocol endpoint/low confidence

AUC Total GIP

Time frame:Approximately 6 weeks (range 9 - 60 days / 8.5 weeks)

concentration, descriptive

Provenance

Sources

Trial identity, design, statusClinicalTrials.gov API v2

Snapshot dateJuly 6, 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 6, 2026 snapshot.