Patients who switched from the GLP-1 drug dulaglutide to the dual GIP/GLP-1 agonist tirzepatide saw an additional 1.2% HbA1c drop, 3.6 kg weight loss, and improved liver enzymes over 6 months.
-1.2% HbA1c + -3.6 kgSwitching from a GLP-1 agonist to the dual GIP/GLP-1 agonist tirzepatide produced additional blood sugar and weight improvements beyond what dulaglutide achieved
What the researchers found
Switching from dulaglutide to tirzepatide produced average reductions of 1.2% in HbA1c and 3.6 kg in body weight at 6 months. Liver enzymes (AST, ALT, GGT) significantly decreased. HbA1c reduction correlated with higher baseline HbA1c, while weight loss was baseline-independent. Fibrosis-4 index trended toward improvement in those with higher baseline values.
Why it matters
Many patients on GLP-1 monotherapy don't achieve optimal control. This study provides real-world evidence that switching to a dual-pathway peptide (tirzepatide) can deliver additional metabolic and liver benefits, which is clinically relevant as physicians decide when and how to escalate therapy.
The numbers in context
40 patients with type 2 diabetes switched from dulaglutide to tirzepatide. Blood glucose, body weight, and liver function tracked.
How the study worked
Single-center retrospective study in Japan. 40 patients with type 2 diabetes who switched from dulaglutide to tirzepatide were analyzed at 3 and 6 months post-switch. Outcomes: HbA1c, body weight, AST, ALT, GGT, and fibrosis-4 index.
Who was studied
Type 2 diabetes patients switching from dulaglutide to tirzepatide
What this study cannot tell us
Very small sample (40 patients). Single-center retrospective design. No control group. 6-month follow-up may miss longer-term effects. Japanese population may not represent other ethnic groups. Specific tirzepatide doses not detailed in abstract.
How to read the evidence
Rated preliminary: very small (n=40), single-center, retrospective study with no control group. Provides early signal but needs confirmation in larger studies.
When this study was published
Published in 2024. Among the first real-world switch studies from GLP-1 to dual GIP/GLP-1 agonist therapy.
The bigger picture
This supports the growing evidence that dual GIP/GLP-1 peptide agonism (tirzepatide) outperforms GLP-1-only agonists. The liver improvements are particularly notable given the rising prevalence of metabolic liver disease in diabetic patients.
Questions still open
- Would switching from semaglutide (rather than dulaglutide) to tirzepatide show similar additional benefits?
- Could the liver improvements translate to histologic MASH resolution with longer treatment?
- Is the dual GIP/GLP-1 mechanism or simply greater potency driving the superior results?
Common questions
Is tirzepatide better than dulaglutide for diabetes?
Can switching diabetes medications improve liver health?
Read the original research
Effects of the switch from dulaglutide to tirzepatide on glycemic control, body weight, and fatty liver: a retrospective study.
Journal of diabetes and metabolic disorders, 23(2), 2105-2113
Citation
Sawamura, Toshitaka; Mizoguchi, Ren; Ohmori, Ai; Kometani, Mitsuhiro; Yoneda, Takashi; Karashima, Shigehiro. (2024). Effects of the switch from dulaglutide to tirzepatide on glycemic control, body weight, and fatty liver: a retrospective study.. Journal of diabetes and metabolic disorders, 23(2), 2105-2113. https://doi.org/10.1007/s40200-024-01472-w