Recruiting

Metformin vs. InsulinDECIDE: A Comparative Effectiveness Trial of Metformin Versus Insulin for the Treatment of Gestational Diabetes

Sponsor:

Ohio State University

Code:

NCT06445946

Conditions

Gestational Diabetes Mellitus

Pregnancy, High Risk

Eligibility Criteria

Sex: Female

Age: 18+

Healthy Volunteers: Not accepted

Interventions

Metformin

Insulin

Study Details

Brief summary:

This is a non-inferiority patient-centered and pragmatic comparative-effectiveness pregnancy randomized controlled trial (RCT) with postpartum maternal and child follow-up through 2 years of 1,572 individuals with gestational diabetes mellitus (GDM) randomized to oral metformin versus injectable insulin.

This study will determine if metformin is not inferior to insulin in reducing adverse pregnancy outcomes, is comparably safe for exposed individuals and children, and if patient-reported factors, including facilitators of and barriers to use, differ between metformin and insulin. A total of 1,572 pregnant individuals with GDM who need pharmacotherapy will be recruited at 20 U.S. sites using consistent treatment criteria to metformin versus insulin. Participants and their children will be followed through delivery to two years postpartum.

Conditions

Gestational Diabetes Mellitus

Pregnancy, High Risk

Study ID

NCT06445946

Start date

Aug 1, 2024

Status verified date

Jun, 2026

Completion date

Dec, 2030

Anticipated

Primary completion date

Dec, 2029

Anticipated

Eligibility Criteria

Sex: Female

Age: 18+

Healthy Volunteers: Not accepted

Inclusion Criteria:

Singleton gestation. Twin reduction to singleton, either spontaneously or therapeutically, is eligible if it occurred before 14 weeks gestational age.
Age 18 years or older
Gestational age at randomization between 20 0/7 - 33 6/7 weeks based on project gestational age.
GDM diagnosis less than or equal to 33 6/7 weeks based on project gestational age.
Requires medication for glucose control defined as ≥ 30% elevated glucose values (either fasting or postprandial or both) prior to randomization per determination of the provider or documented in the medical record.
Patient willingness and ability to attend 2-year follow-up visit.

Exclusion criteria:

Renal disease (serum creatinine >1.3 mg/dL) due to the potential impact of metformin on renal function.
Major structural malformation of the fetus.
Known fetal aneuploidy based on invasive testing or positive for aneuploidy on cell-free fetal DNA screening.
Contraindication to metformin or insulin, including: history of lactic acidosis, intractable nausea and vomiting, prior documented allergy and/or anaphylaxis.
For individuals with GDM diagnosed <20 0/7 weeks, documented A1c ≥>6.5% within prior 6 months.
Pregestational diabetes documented in the medical record or prior A1c>= 6.5%
Fasting hyperglycemia >115 mg/dl for ≥ 50% of fasting glucose values in the past week (due to the high risk of metformin failure with fasting hyperglycemia).
Enrolled in a trial that influences primary study outcomes (composite neonatal outcome at delivery or childhood body mass index at 2 years).
Prenatal care or delivery planned at a location where access to the complete electronic medical record will not be available to research staff.
Language barrier (appropriate translation resources unavailable at the site)
Participation in this trial in a previous pregnancy. Patients who were screened in a previous pregnancy, but not randomized, may be included.

Study Design

Enrollment

1572 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Metformin

Metformin as either immediate- or extended-release formulations can be utilized, and titrated to a maximum daily dose of 2,500 mg. Participants receiving metformin will have insulin added only if they have not achieved euglycemia for at least 30% of glucose values after generally receiving the maximum daily dose of metformin of 2,500 mg, or in select situations in the setting of participant intolerance due to mild gastrointestinal symptoms. Participants will be asked to continue taking metformin after treatment supplementation with insulin.

experimental: Insulin

Insulin will be initiated utilizing clinical standards using trimester-specific weight-based dosing criteria, including both basal and prandial insulins for up to a total of 4 daily injections. Consistent with clinical practice, some people may be managed with a single dose of intermediate- or long-acting insulin at night to treat isolated fasting hyperglycemia, while others may require additional treatment of postprandial hyperglycemia with shorter-acting insulin. The sites' insulin formularies include rapid- (Novolog and Humalog), intermediate- (Humulin N, Novolin N, and NPH), and long-acting insulins (Detemir and Lantus).

Interventions

Metformin

Individuals randomized to this arm will receive oral metformin tablets for their Gestational diabetes mellitus treatment.

Insulin

Individuals randomized to this arm will receive injectable insulin for their Gestational diabetes mellitus treatment.

Primary outcome measure

A neonatal composite adverse outcome of large-for-gestational-age (LGA) birthweight, hypoglycemia, hyperbilirubinemia, and/or death. [ Time Frame: LGA at birth. Hypoglycemia <24 hours after birth. Hyperbilirubinemia within the first week after birth. Death between randomization to hospital discharge or 30 days postnatal. ]
Child body mass index (BMI) at 2 years of age [ Time Frame: 2 years of age. ]

Central Contacts and Locations

Central contacts

Kartik Venkatesh, MD, PhD

614-293-2222 kartik.venkatesh@osumc.edu

Anna Bartholomew, MPH, BS, RN

614-685-3229 Anna.Bartholomew@osumc.edu

Locations

University of Alabama

Recruiting

Tuscaloosa, Alabama, United States, 35487

Contacts

Ashley Battarbee, MD

anbattarbee@uabmc.edu

Michael Jordan

mejordan@uabmc.edu

Principal Investigator:

Ashley Battarbee, MD

Cedars Sinai Medical Center

Recruiting

Los Angeles, California, United States, 90048

Contacts

Tania Esakoff, MD

Tania.esakoff@cshs.org

Marla Sharp

Marla.Sharp@cshs.org

Principal Investigator:

Tania Esakoff, MD

University of California San Francisco

Recruiting

San Francisco, California, United States, 94143

Contacts

Nasim Sobhani, MD

Nasim.sobhani@ucsf.edu

Magie Fong

magie.fong@ucsf.edu

Principal Investigator:

Nasim Sobhani, MD

University of South Florida

Recruiting

Tampa, Florida, United States, 33620

Contacts

Anjali Kaimal Kaimal, MD

akaimal@usf.edu

Maha Jumaily

mahaaljumaily@usf.edu

Principal Investigator:

Anjali Kaimal, MD

Tufts University

Recruiting

Boston, Massachusetts, United States, 02111

Contacts

Erika Werner, MD

erika.werner@tuftsmedicine.org

Beth Marsh

Beth.Marsh@tuftsmedicine.org

Principal Investigator:

Erika Werner, MD

Massachusetts General Hospital

Recruiting

Boston, Massachusetts, United States, 02114

Contacts

Lydia Shook, MD

lshook@mgh.harvard.edu

Nancy Kingori

nkingori@mgb.org

Principal Investigator:

Lydia Shook, MD

Washington University in St. Louis

Recruiting

St Louis, Missouri, United States, 63130

Contacts

Megan Lawlor, MD

lawlor@wustl.edu

Emily Diveley, BSN, RN

314-362-4685 diveley@wustl.edu

University of New Mexico

Recruiting

Albuquerque, New Mexico, United States, 87131

Contacts

Vivek Katukuri, MD

vkatukuri@salud.unm.edu

Karen Taylor

kataylor@salud.unm.edu

Principal Investigator:

Vivek Katukuri, MD

Columbia University Irving Medical Center

Recruiting

New York, New York, United States, 10032

Contacts

Noelia Zork, MD

nmz2110@cumc.columbia.edu

Joseph Celentano

jmc2476@cumc.columbia.edu

Principal Investigator:

Noelia Zork, MD

Wake Forest University

Recruiting

Winston-Salem, North Carolina, United States, 27106

Contacts

David Stamilio, MD

dstamili@wakehealth.edu

Christina Tulbert

ctulbert@wakehealth.edu

Principal Investigator:

David Stamilio, MD

The Ohio State University Wexner Medical Center OB/GYN Maternal and Fetal Medicine

Recruiting

Columbus, Ohio, United States, 43210

Contacts

Kartik Venkatesh, MD, PhD

614-293-2222 Kartik.Venkatesh@osumc.edu

Principal Investigator:

Kartik Venkatesh, MD, PhD

Premier Health - Miami Valley Hospital

Recruiting

Dayton, Ohio, United States, 45409

Contacts

Samantha Wiegand, MD

slwiegand@premierhealth.com

Emily Reynolds

ESReynolds@premierhealth.com

Principal Investigator:

Samantha Wiegand, MD

University of Pennsylvania

Recruiting

Philadelphia, Pennsylvania, United States, 19104

Contacts

Celeste Durnwald, MD

215-615-3817 Celeste.Durnwald@pennmedicine.upenn.edu

Elizabeth Norton, MPH, MBE

215-615-3817 Elizabeth.Norton@pennmedicine.upenn.edu

University of Pittsburgh

Recruiting

Pittsburgh, Pennsylvania, United States, 15213

Contacts

Maisa Feghali, MD

feghalim@mwri.magee.edu

John Collins

collinsjn@mwri.magee.edu

Principal Investigator:

Maisa Feghali, MD

Brown University

Recruiting

Providence, Rhode Island, United States, 02912

Contacts

Martha Kole-White, MD

mkolewhite@kentri.org

Kelsey Inglesby

KInglesby@Wihri.org

Principal Investigator:

Martha Kole-White, MD

University of South Carolina Greenville

Recruiting

Greenville, South Carolina, United States, 29605

Contacts

Kacey Eichelberger, MD

kacey.eichelberger@prismahealth.org

Patti Parker

patti.parker@prismahealth.org

Principal Investigator:

Kacey Eichelberger, MD

University of Texas Austin

Recruiting

Austin, Texas, United States, 78705

Contacts

Lorie Harper, MD

lorie.harper@austin.utexas.edu

Mickey Roberts

Mickey.roberts@austin.utexas.edu

Principal Investigator:

Lorie Harper, MD

University of Texas Health Science Center

Recruiting

Houston, Texas, United States, 77030

Contacts

Hector Mendez-Figueroa, MD

hector.mendezfigueroa@uth.tmc.edu

Laura Nixon

Laura.Nixon@uth.tmc.edu

Principal Investigator:

Hector Mendez-Figueroa, MD

Eastern Virginia Medical School - Old Dominion University

Recruiting

Norfolk, Virginia, United States, 23501

Contacts

Malgorzata Mlynarczyk, MD

mlynarm@evms.edu

Cheryl Sparrer

SparreCD@evms.edu

Principal Investigator:

Malgorzata Mlynarczyk, MD

More Information

Sponsor

Ohio State University

Last update posted

Jun 25, 2026

Last verified

Jun, 2026

Keywords

Insulin
Pregnancy
Glycemic control
Metformin
Gestational diabetes
Diabetes
Adverse pregnancy outcomes

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-08. This information was provided to ClinicalTrials.gov by Ohio State University on 2026-06-25.