New weekly diabetes jab cuts blood sugar, body weight in major trial

Dubai: A new weekly diabetes injection significantly reduced blood sugar levels and body weight in adults with type 2 diabetes, according to results from a phase 3 trial published in The Lancet.

The experimental drug, retatrutide, reduced long-term blood sugar levels and led to double-digit weight loss among adults with type 2 diabetes, raising hopes for a new treatment option in a field currently dominated by drugs such as Ozempic and Mounjaro.

The findings, published in the medical journal The Lancet, are based on a phase 3 trial involving 930 adults with type 2 diabetes. Participants received weekly injections of retatrutide at different doses or a placebo for 40 weeks.

Researchers found that patients taking retatrutide experienced average reductions in HbA1c — a key measure of long-term blood sugar control — of between 1.7 and 1.9 percentage points, compared with 0.8 percentage points among those given a placebo.

The weight-loss results were equally striking. Participants receiving retatrutide lost between 11.5% and 15.3% of their body weight on average, compared with 2.6% in the placebo group.

Unlike existing medications that target one or two hormone pathways, retatrutide acts on three hormones involved in appetite regulation, blood-sugar control and metabolism. The drug mimics GLP-1, GIP and glucagon, a combination researchers believe may help explain its strong impact on both weight and glucose levels.

The trial also found improvements in cholesterol levels and blood pressure among participants taking the medication.

While 14 participants experienced serious adverse events during the study, researchers said most side-effects were mild to moderate and eased over time. Gastrointestinal symptoms such as nausea and digestive discomfort were the most commonly reported side-effects.

The authors said the drug could offer meaningful benefits for people who need more intensive treatment to manage type 2 diabetes and obesity, although further studies are continuing.

The results follow earlier findings from the drug's manufacturer, Eli Lilly, which suggested retatrutide was highly effective in helping people with obesity lose weight.

Independent experts welcomed the findings but urged caution.

Dr Kath McCullough, special adviser on obesity at the Royal College of Physicians, described the results as encouraging and said treatments such as retatrutide could be life-changing for many people living with obesity and diabetes.

However, she stressed that medication alone is not the answer and that preventing obesity and type 2 diabetes remains the long-term goal, according to The Guardian.

Other researchers noted that direct comparisons with existing drugs such as semaglutide and tirzepatide have not yet been carried out.

Dr Marie Spreckley of the University of Cambridge said the amount of weight loss seen in the study was particularly notable, but added that it remains unclear whether retatrutide is superior, equivalent or inferior to currently available treatments because no head-to-head comparisons were conducted.

Diabetes UK also welcomed the findings, saying the drug appears capable of delivering both weight-loss and blood-sugar benefits, while calling for more research into its long-term effects and effectiveness compared with existing therapies.