Weekly semaglutide helped adults with type 1 diabetes and obesity reach blood sugar and weight goals in first randomized trial

Adults with type 1 diabetes and obesity who took once-weekly semaglutide along with an automated insulin delivery (AID) system were much more likely than those on placebo to meet combined blood sugar and weight goals over 26 weeks, according to results published June 23, 2025, in NEJM Evidence ^[1]. The trial, called ADJUST-T1D, is described as the first randomized evidence for semaglutide in type 1 diabetes ^[2].

Semaglutide is sold as Ozempic, Wegovy and Rybelsus and is approved for type 2 diabetes and obesity; its use in type 1 diabetes remains investigational ^[2].

What the trial measured

The study assigned 72 adults with type 1 diabetes in a 1-to-1 ratio to once-weekly semaglutide up to 1 mg or a placebo, with neither the participants nor the researchers knowing which treatment was given ^[1]. Everyone enrolled used an AID system and had a body mass index of 30 or higher ^[1]. Participants were treated at four medical centers, including Oregon Health & Science University ^[2].

The main goal combined three targets: spending more than 70 percent of continuous glucose monitor time between 70 and 180 mg/dl, spending less than 4 percent of time below 70 mg/dl, and losing at least 5 percent of body weight ^[1].

Thirty-six percent of the semaglutide group met all three targets, compared with none in the placebo group — a difference of 36 percentage points (95% CI, 20.6 to 52.2; P<0.001) ^[1]. In other words, most people taking semaglutide did not meet all three goals.

For the individual measures, the difference between groups was minus 0.3 percentage points for glycated hemoglobin (A1C) (95% CI, minus 0.6 to minus 0.05), 8.8 percentage points for time in the 70-to-180 mg/dl range (95% CI, 3.9 to 13.7), and minus 8.8 kg (about 19 pounds) for body weight (95% CI, minus 10.6 to minus 7.0) ^[1].

The journal reports weight as a difference between the two groups, while the university's news release describes an average loss of about 18.5 pounds among participants taking semaglutide over six months ^[1][2].

For safety, two severe hypoglycemia events occurred in each group, and no diabetic ketoacidosis was reported ^[1]. "Semaglutide helped more people reach their blood sugar and weight goals without decreasing blood sugar," said Andrew Ahmann, M.D., an emeritus professor of medicine at Oregon Health & Science University and a co-author, in the university's announcement ^[2]. The trial was funded by Breakthrough T1D, and Novo Nordisk provided the drug and a matching placebo at no cost ^[1].

Why it matters for patients

Type 1 diabetes is usually treated with insulin, and semaglutide is not approved for it, so anyone using the drug for type 1 diabetes is outside its labeled use ^[2]. This trial does not change that approval status.

Because everyone in the study used an AID system, results in people who take insulin by injection or use other regimens have not been reported ^[1]. The study lasted 26 weeks, so effects and risks beyond that period have not been reported from this trial, and rare complications may not appear in a study of 72 people.

How the findings might apply to insurance coverage, cost, or use at other semaglutide doses has not been disclosed. The trial tested doses up to 1 mg weekly ^[1].

What happens next

The results were published online June 23, 2025, and appear in the July 22, 2025, issue of NEJM Evidence ^[1]. The trial is registered at Clinicaltrials.gov as NCT05537233 ^[1][2]. No plans for regulatory submission, larger trials, or a follow-up study were described in the journal abstract or the university announcement ^[1][2].