- βTirzepatide reduced HbA1c by ~2.4% compared to just 0.9% with placebo β a clinically significant improvement
- βSide effects like nausea, vomiting, and diarrhoea were mostly mild to moderate and manageable
- βResults are specifically from Chinese patients, making findings more relevant for this population
| Journal | The lancet. Diabetes & endocrinology |
| Year | 2025 |
| PMID | 41167231 |
What Was This Study About?
Researchers in China tested whether adding tirzepatide (a once-weekly injection) to existing basal insulin therapy could better control blood sugar in people with type 2 diabetes whose levels were not adequately managed.
Who Was Involved?
The trial included 257 adults across 26 hospitals in China. Participants already used daily insulin glargine, with some also taking metformin or an SGLT2 inhibitor. The study ran for 40 weeks and was carefully designed so neither patients nor doctors knew who received the real medication versus a placebo.
What Did They Find?
Patients who added tirzepatide (10 mg or 15 mg) to their insulin saw their HbA1c drop by about 2.4% on average β compared to only 0.9% in the placebo group. This is a meaningful difference that can significantly reduce the risk of long-term diabetes complications.
What About Side Effects?
The most common side effects were:
- Diarrhoea β reported in 26β37% of tirzepatide users vs. 8% on placebo
- Decreased appetite β reported in 25β32% of tirzepatide users vs. none on placebo
- Upper respiratory tract infections β similar rates in both groups
- Nausea and vomiting β occurred but were mostly mild or moderate
Overall, most side effects were manageable and did not cause patients to stop treatment.
Why Does This Matter for Patients?
Many people with type 2 diabetes struggle to reach their blood sugar targets even on insulin. This study shows that adding tirzepatide to insulin is an effective and generally safe option β now with evidence specific to Chinese patients, who may respond differently to medications than Western populations.
Bottom Line
Tirzepatide added to basal insulin is a promising treatment upgrade for people with uncontrolled type 2 diabetes, offering significantly better blood sugar control with side effects that are mostly mild and temporary.