CagriSema Phase 3a: what the REIMAGINE 1 diabetes trial found

What the source reports

A Phase 3a trial published in The Lancet Diabetes & Endocrinology tested CagriSema in adults with type 2 diabetes whose blood glucose was not adequately controlled with diet and exercise alone. CagriSema is an investigational once-weekly injection combining cagrilintide, a long-acting amylin analogue, with the GLP-1 receptor agonist semaglutide.

After 40 weeks, both tested dose combinations produced statistically greater average reductions in HbA1c and body weight than placebo. The higher-dose combination reduced model-estimated average HbA1c by 1.8 percentage points and body weight by 13.8% from baseline.

Those are notable late-stage findings in a selected early-diabetes population. They do not mean CagriSema is approved, available to prescribe or proven superior to an existing diabetes or obesity medicine.

Why combine amylin with GLP-1?

Semaglutide acts at the GLP-1 receptor. Cagrilintide is designed to mimic amylin, a hormone co-secreted with insulin that contributes to fullness and helps regulate food intake. CagriSema brings the two mechanisms together in one weekly treatment.

The scientific idea is that complementary appetite and metabolic signals may produce effects that one pathway alone does not. REIMAGINE 1, however, compared the combinations with placebo rather than with semaglutide or cagrilintide alone, so this trial cannot isolate how much each component contributed.

CagriSema and cagrilintide remain investigational. Semaglutide is already approved for specified uses, but that does not confer approval on a new fixed-dose combination containing it.

How REIMAGINE 1 worked

The randomised, double-blind study enrolled 189 adults at 42 sites in the United States, China, Hungary, Italy, Poland and Serbia. Participants had type 2 diabetes inadequately controlled with diet and exercise and were assigned to CagriSema containing 2.4 mg of each component, CagriSema containing 1.0 mg of each component, or matching placebo.

Treatment lasted 40 weeks. Participants, care providers, investigators and outcome assessors were masked within each dose level, with visually identical injections used to preserve masking.

At baseline, average HbA1c was 7.8% and average body mass index was 35.2 kg/m². The average age was 53.6 years; 54% of participants were men, 46% were women, 78% were White and 14% were Asian.

The blood-glucose results

Using the trial's efficacy estimand, model-estimated average HbA1c fell by 1.8 percentage points with CagriSema 2.4 mg/2.4 mg and by 1.5 percentage points with CagriSema 1.0 mg/1.0 mg. The corresponding change with placebo was 0.1 percentage points.

The estimated differences from placebo were −1.7 percentage points for the higher dose and −1.3 percentage points for the lower dose. Both comparisons met the trial's threshold for statistical significance.

HbA1c reflects average blood glucose over the preceding months. A group-average fall does not predict the result for an individual, and this study was not designed to show whether the treatment prevents long-term diabetes complications.

The body-weight results

At week 40, model-estimated average body-weight change was −13.8% with CagriSema 2.4 mg/2.4 mg, −11.8% with CagriSema 1.0 mg/1.0 mg and −1.4% with placebo. The estimated placebo-adjusted differences were −12.4 and −10.4 percentage points, respectively.

In the higher-dose group, an estimated 90% reached at least 5% weight reduction, 63% reached at least 10% and 47% reached at least 15%. The corresponding placebo estimates were 27%, 6% and 1%.

These percentages should not be placed beside results from unrelated semaglutide, tirzepatide or retatrutide trials as though they were a direct ranking. Trial populations, treatment periods, support, doses and statistical methods differ.

Gastrointestinal effects were common

At least one adverse event was reported by 79% of participants receiving the higher-dose combination, 75% receiving the lower-dose combination and 66% receiving placebo. Most events were described as mild or moderate.

Gastrointestinal events occurred in 53% of the higher-dose group, 44% of the lower-dose group and 20% of the placebo group. Nausea was among the most commonly reported events.

Two participants in each of the three groups permanently stopped treatment because of an adverse event. That is about 3% of each group, although a trial this size provides only a limited estimate of tolerability in wider use.

What the safety data show—and cannot show

Serious adverse events occurred in four participants in each CagriSema group and three receiving placebo. No deaths occurred during the study.

The authors reported that the overall profile was consistent with previous evidence for GLP-1 receptor agonists and cagrilintide. That is reassuring within this trial, but 189 participants followed for 40 weeks cannot reveal very rare harms or establish long-term safety.

Larger exposure, longer follow-up and regulatory review are needed to characterise risks across people with different health conditions and background medicines.

What remains uncertain

REIMAGINE 1 asked whether two CagriSema dose combinations worked better than placebo in people at an early treatment stage. It did not include a semaglutide-only, cagrilintide-only, tirzepatide or other active-comparator group.

The study therefore supports efficacy against placebo, but cannot answer whether the combination offers a clinically worthwhile advantage over an approved treatment. Other trials in the REIMAGINE programme address different populations and comparisons; their designs and results must be assessed separately.

It also remains uncertain how much benefit would persist after treatment stops and how the balance of effectiveness, tolerability, access and cost would look in routine care.

Population and sponsor limitations

The trial population was small and predominantly White. Participants were specifically selected for type 2 diabetes not adequately controlled by diet and exercise, so the findings do not automatically apply to people already using multiple glucose-lowering medicines, those without diabetes or more medically complex populations.

Novo Nordisk funded the trial and is developing CagriSema. Three authors were company employees, and several academic authors disclosed research funding, consulting or other relationships with pharmaceutical companies.

Industry funding does not by itself invalidate a randomised peer-reviewed trial, but sponsor involvement, replication and the complete regulatory evidence package are relevant when interpreting a commercial product's results.

What this means for the individual

CagriSema is not currently an approved treatment and should not be sourced as an unregulated peptide or mixed at home. Research doses are specific to the studied combination and cannot be recreated by combining other products.

For someone taking semaglutide or another diabetes or weight-management medicine, this trial is not a reason to change treatment. It is evidence about a possible future option for a defined patient group.

Any treatment decision should be based on an approved indication, personal medical history, potential adverse effects and discussion with a qualified healthcare professional.

Bottom line

In a 40-week Phase 3a trial involving 189 people with early-stage type 2 diabetes, investigational CagriSema produced substantial average reductions in HbA1c and body weight compared with placebo. The higher-dose combination was associated with a 1.8-percentage-point HbA1c reduction and 13.8% weight reduction in the primary efficacy analysis.

The result strengthens the case for combining amylin and GLP-1 pathways, but it is not a head-to-head verdict on current medicines. Gastrointestinal effects were common, the study was relatively small and CagriSema still requires regulatory assessment before it could become a treatment option.