Automated Insulin Delivery Provides Additive Benefits to GLP-1 Drugs in Type 2 Diabetes — Without Weight Gain | Research

The takeaway

Adding automated insulin delivery (Control-IQ+) to GLP-1 receptor agonist therapy reduced HbA1c by an additional 0.5% in type 2 diabetes patients, with significant glycemic improvements and no weight gain — unlike non-GLP-1 users who gained 1.9 kg.

-0.5% HbA1c, 0 weight gain
Adding automated insulin delivery to GLP-1 therapy reduced HbA1c by an additional 0.5 percentage points without causing weight gain — a combination of benefits not achievable with either technology alone.

What the researchers found

Among 143 GLP-1 RA users in the 319-participant randomized trial:

- HbA1c decreased 0.8% from baseline (8.0 ± 1.2%) with AID, representing a 0.5% improvement vs. CGM group (95% CI: -0.8 to -0.3, p < 0.001)

- Time-in-range (70-180 mg/dL) and hyperglycemia metrics showed statistically significant improvements

- No significant weight difference with AID vs. CGM in GLP-1 users (+0.9 kg, 95% CI: -0.2 to 2.1, p = 0.10)

- In contrast, GLP-1 non-users gained 1.9 kg with AID vs. CGM (95% CI: 0.5 to 3.2, p = 0.007)

- Insulin use was simultaneously reduced alongside glycemic improvements

The combination of improved blood sugar control, reduced insulin requirements, and weight neutrality demonstrates clear additive benefits of combining AID with GLP-1 therapy.

Why it matters

This is the first randomized trial evidence showing that automated insulin delivery provides meaningful additional benefits even for patients already on optimal GLP-1 therapy — the current gold standard of diabetes treatment. The weight neutrality finding is particularly important: insulin therapy typically causes weight gain, which undermines metabolic benefits. By showing that GLP-1 drugs prevent this AID-associated weight gain, the study provides a strong rationale for combining these two technologies as complementary therapies.

How the study worked

This was a subgroup analysis from a randomized controlled trial comparing Control-IQ+ automated insulin delivery (AID) versus continuation of the pre-study insulin delivery method plus continuous glucose monitoring (CGM). Of 319 total participants with insulin-treated type 2 diabetes, 143 (45%) were using a GLP-1 RA at baseline and continued it during the 13-week trial. Outcomes included HbA1c change, CGM-derived glycemic metrics (time-in-range, hyperglycemia), insulin doses, and body weight.

What this study cannot tell us

This is a subgroup analysis of a larger randomized trial, which reduces statistical power and may be subject to selection bias (GLP-1 use was not randomized). The 13-week duration is relatively short for assessing long-term glycemic and weight outcomes. Specific GLP-1 drugs and doses were not standardized across participants. The study population was insulin-treated type 2 diabetes, which represents a specific subset of all T2D patients. Cost and insurance coverage implications of combining AID technology with GLP-1 drugs were not addressed.

How to read the evidence

This is a pre-specified subgroup analysis from a randomized controlled trial published in Diabetes Care. While the overall trial is high-quality, the GLP-1 subgroup analysis has reduced power and GLP-1 use was not randomized, placing it at a moderate-high evidence level.

When this study was published

Published in 2025, this is a very current study at the forefront of combining diabetes technologies. Automated insulin delivery systems and GLP-1 drugs are both rapidly evolving.

The bigger picture

This study represents the convergence of two major diabetes technology trends: GLP-1 peptide drugs and automated insulin delivery ('artificial pancreas') systems. As both technologies become more accessible, understanding how they work together is critical. The finding that GLP-1 drugs prevent AID-associated weight gain suggests these are truly complementary: the automated system optimizes insulin delivery moment-to-moment, while the GLP-1 drug provides weight protection, appetite suppression, and additional metabolic benefits that insulin alone cannot achieve.

Questions still open

Would combining newer GLP-1 drugs (semaglutide, tirzepatide) with AID produce even larger benefits than the mixed GLP-1 drugs used in this trial?
Could this AID + GLP-1 combination allow some patients to reduce or eliminate basal insulin entirely over time?
What is the cost-effectiveness of adding AID technology for patients already achieving good control on GLP-1 therapy alone?

Common questions

What is automated insulin delivery and how does it work with GLP-1 drugs?

Automated insulin delivery (sometimes called an 'artificial pancreas') uses a continuous glucose monitor and an insulin pump controlled by a computer algorithm to automatically adjust insulin delivery throughout the day. When combined with GLP-1 drugs (like semaglutide), you get the best of both worlds: the pump handles moment-to-moment insulin needs, while the GLP-1 drug controls appetite, weight, and provides additional metabolic benefits.

Will I gain weight if I start using an insulin pump while on a GLP-1 drug?

This study found that patients using GLP-1 drugs who added automated insulin delivery did NOT gain significant weight over 13 weeks — while those not on GLP-1 drugs gained an average of 1.9 kg. This suggests that GLP-1 drugs effectively prevent the weight gain typically associated with more intensive insulin therapy.

Read the original research

Additive Benefits of Control-IQ+ AID to GLP-1 Receptor Agonist Use in Adults With Type 2 Diabetes.

Diabetes care, 48(12), 2154-2159

View on PubMed ↗Publisher’s paper ↗

Citation

Graham, Timothy E; Raghinaru, Dan; Afreen, Samina; Ahmann, Andrew; Haidar, Ahmad; Raskin, Philip; Tsoukas, Michael A; Lum, John W; Sasson-Katchalski, Ravid; Pinsker, Jordan E; Beck, Roy W. (2025). Additive Benefits of Control-IQ+ AID to GLP-1 Receptor Agonist Use in Adults With Type 2 Diabetes.. Diabetes care, 48(12), 2154-2159. https://doi.org/10.2337/dc25-1753