Survodutide has new Phase 3 data. Results from the SYNCHRONIZE-2 trial, published October 1, 2026 in The New England Journal of Medicine, show significant weight loss and improved glycemic control in adults with obesity or overweight and type 2 diabetes. New SYNCHRONIZE-JP results released October 5 add data in Japanese adults with obesity, including MRI findings on visceral and liver fat.
What is survodutide?
Survodutide, also known as BI 456906, is an investigational once-weekly glucagon receptor and GLP-1 receptor dual agonist being developed by Boehringer Ingelheim in partnership with Zealand Pharma. It is being studied for obesity and related metabolic conditions.
Survodutide is investigational and is not FDA-approved. The results discussed here come from controlled clinical trials and should not be interpreted as instructions for personal use.
SYNCHRONIZE-2 Phase 3 results
SYNCHRONIZE-2 was a multinational, randomized, double-blind Phase 3 trial in adults with type 2 diabetes and a BMI of at least 27. The published analysis included 752 participants assigned to once-weekly survodutide 3.6 mg, survodutide 6.0 mg, or placebo for 76 weeks.
The study met its co-primary endpoints for change in body weight and the proportion of participants achieving at least 5% weight loss.
How much weight did participants lose?
There are two sets of numbers worth understanding. In the treatment-regimen analysis—which counts outcomes regardless of treatment discontinuation, interruption, or use of other anti-obesity therapy—mean weight change at week 76 was -8.2% with 3.6 mg and -9.8% with 6.0 mg, compared with -3.9% with placebo.
Boehringer Ingelheim also reported an efficacy-estimand analysis designed to estimate the treatment effect under continued treatment. In that analysis, average weight loss reached up to 13.1%, versus 3.1% with placebo. Up to 79.3% of participants receiving survodutide achieved at least 5% weight loss, versus 32.7% with placebo.
That distinction matters when comparing headlines about the trial: the widely reported 13.1% figure and the 9.8% figure come from different prespecified statistical approaches, rather than conflicting reports.
Blood sugar and metabolic findings
Participants entered the trial with a mean HbA1c of 7.4%. In the NEJM treatment-regimen analysis, mean HbA1c declined by 0.9 percentage points in the 3.6-mg group and 0.8 percentage points in the 6.0-mg group, versus 0.2 percentage points with placebo. Boehringer reported reductions of up to 1.21 percentage points using its efficacy analysis, along with improvements in waist circumference and insulin sensitivity.
New October 5 SYNCHRONIZE-JP results
On October 5, Boehringer Ingelheim announced additional Phase 3 results from SYNCHRONIZE-JP in Japanese adults living with obesity. At week 76, reported mean weight reductions were 12.5% with 3.6 mg and 13.1% with 6.0 mg, compared with 1.6% with placebo.
An MRI-assessed subgroup produced another notable finding. Boehringer reported visceral fat reductions of 27.9% and 25.0% in the two survodutide groups, while placebo increased 2.3%. Liver fat declined 56.0% and 63.1% in the survodutide groups, while increasing 16.2% with placebo. These figures are company-reported trial results and should be interpreted in the context of the full study once detailed peer-reviewed data are available.
Side effects and discontinuations matter
The efficacy numbers are only part of the story. Gastrointestinal adverse events were common in SYNCHRONIZE-2. The NEJM report states that GI events occurred in 72.8% of participants receiving 3.6 mg and 77.7% receiving 6.0 mg, compared with 38.6% receiving placebo. Events were generally described as mild to moderate and transient.
Tolerability and treatment discontinuation will be important to watch as the broader Phase 3 program develops. They can materially affect how a therapy performs outside the narrower question of how much weight participants who remain on treatment may lose.
How does survodutide work?
Survodutide targets both the GLP-1 receptor and glucagon receptor. GLP-1 receptor activation is associated with appetite regulation and glucose control, while glucagon-receptor activity is being investigated for its potential effects on energy expenditure and liver metabolism. That dual mechanism differentiates survodutide from GLP-1-only therapies and from investigational multi-receptor drugs that target different combinations of metabolic pathways.
What happens next for survodutide?
SYNCHRONIZE-2 is one part of a larger Phase 3 development program. The new results strengthen the clinical evidence for survodutide, but the drug remains investigational. Regulatory review, additional Phase 3 results, longer-term safety and tolerability data, and the eventual approved indication—if regulators approve it—will determine its place in obesity treatment.
The bottom line
Survodutide’s Phase 3 program has now produced significant weight-loss results in multiple populations, with SYNCHRONIZE-2 adding important data for adults who also have type 2 diabetes. The October 5 Japanese results add an intriguing body-composition signal, particularly around visceral and liver fat. At the same time, the high frequency of gastrointestinal adverse events means tolerability deserves as much attention as the headline weight-loss percentage.
PepDiscounts will continue tracking published survodutide research, regulatory developments, and major Phase 3 updates as new data become available.
