In 123 real-world patients with type 2 diabetes, switching from weekly dulaglutide to weekly semaglutide produced an additional 0.54% HbA1c reduction and 5.4 kg weight loss at 18 months, with no increase in side effects.
-5.4 kg additional weight lossPeak additional weight loss at 18 months after switching from dulaglutide to semaglutide, on top of prior dulaglutide-related weight loss
What the researchers found
After switching from dulaglutide to semaglutide, patients achieved additional HbA1c reductions of -0.43% (6 mo), -0.54% (12 mo), -0.38% (18 mo), and additional weight loss of -2.7 kg (6 mo), -3.7 kg (12 mo), -5.4 kg (18 mo), -4.2 kg (24 mo), with no significant increase in adverse effects.
Why it matters
Many patients on GLP-1 drugs reach a plateau or have suboptimal results. This study provides real-world evidence that switching between GLP-1 agonists—specifically from dulaglutide to semaglutide—can unlock additional metabolic benefits without added risk.
The numbers in context
123 patients. Prior dulaglutide duration: 16.9 months. Dulaglutide reduced HbA1c by 0.38% and weight by 1.3 kg. After switching to semaglutide: additional HbA1c reductions of 0.43% (6 mo), 0.54% (12 mo), 0.38% (18 mo), 0.12% (24 mo). Additional weight loss up to 5.5 kg.
How the study worked
Real-world observational cohort study (SEMA-SWITCH) of 123 patients with T2DM who switched from subcutaneous dulaglutide to subcutaneous semaglutide, followed for up to 24 months with HbA1c and weight measurements.
Who was studied
Adults with type 2 diabetes switching from dulaglutide to semaglutide
What this study cannot tell us
Observational design without a control group (no comparison to continuing dulaglutide). Selection bias: patients who switched may have been more motivated. Relatively small sample size. HbA1c benefit diminished by 24 months. No randomization.
How to read the evidence
Real-world observational study with reasonable follow-up (24 months) but lacks randomization and control group. Provides practical clinical guidance but lower evidence grade than an RCT.
When this study was published
Published in 2025; represents current real-world data on GLP-1 agonist switching strategies.
The bigger picture
As the GLP-1 drug class expands, clinicians need data on switching between agents. This study confirms that not all GLP-1 agonists are equivalent—semaglutide appears more potent than dulaglutide for both glycemic control and weight loss, making intra-class switching a viable clinical strategy.
Questions still open
- Would patients who are responding adequately to dulaglutide still benefit from switching to semaglutide?
- Does the diminishing HbA1c benefit at 24 months suggest a semaglutide plateau similar to dulaglutide?
- How would tirzepatide compare as a switch option for patients with inadequate dulaglutide response?
Common questions
Why would someone switch from dulaglutide to semaglutide?
Is it safe to switch between GLP-1 drugs?
Read the original research
Real-world evaluation of the efficacy and safety of switching from weekly dulaglutide to weekly semaglutide: The SEMA-SWITCH study.
Endocrinologia, diabetes y nutricion, 72(6), 501574
Citation
Pardo Lozano, Felipe; Rubio Marcos, Arantxa; Casañ Fernández, Rosa; Bartual Rodrigo, Amparo; Martínez-Hervás, Sergio; Ampudia-Blasco, Francisco Javier. (2025). Real-world evaluation of the efficacy and safety of switching from weekly dulaglutide to weekly semaglutide: The SEMA-SWITCH study.. Endocrinologia, diabetes y nutricion, 72(6), 501574. https://doi.org/10.1016/j.endien.2025.501574