Survodutide
Also known as: Survodutide
Boehringer Ingelheim's investigational GLP-1 / glucagon dual agonist. Phase 2 weight loss in the 15–19% range, with a notable side-effect on liver fibrosis in NASH patients.
Overview
Survodutide (formerly BI 456906) is a GLP-1 / glucagon dual agonist sitting between Mazdutide and Retatrutide. The GLP-1 arm handles appetite; the glucagon arm pushes energy expenditure and acts on hepatic fat. Boehringer's Phase 2 obesity trial reported 14.9–18.7% weight loss at 46 weeks, and a separate Phase 2 NASH trial showed meaningful improvement in liver fibrosis — a harder endpoint than the fat-fraction signal most incretins produce. Phase 3 (SYNCHRONIZE) is enrolling. No regulatory approval yet; outside of trials this is research-grade only.[1]
Evidence quality
Boehringer Ingelheim's Phase 2 obesity trial (NEJM 2024) showed 14.9–18.7% weight loss at 46 weeks. A separate Phase 2 NASH trial demonstrated liver-fibrosis improvement in roughly 60% of treated patients. Phase 3 (SYNCHRONIZE-1 through 4) is enrolling, covering obesity, cardiovascular outcomes, and NASH. No approval anywhere as of 2026. The dataset is solid for Phase 2 but smaller than Tirzepatide or Semaglutide by orders of magnitude.
Benefits & timeline
Benefits
- Phase 2 weight loss of ~15–19% at 46 weeks across the dose range
- Meaningful liver-fibrosis improvement in NASH Phase 2 (a stricter endpoint than hepatic fat fraction)
- Glucagon-mediated energy expenditure partially offsets dieting adaptation
- Once-weekly dosing — fits the existing incretin rhythm
Timeline
Week 1–4
0.3 mg starter. Appetite suppression begins, GI symptoms most pronounced.
Week 8–16
Climbing through 0.9, 1.8, 2.7 mg in 4-week steps. Weight loss building steadily.
Week 20–28
On 3.6 mg. Resting heart rate often up 5–8 bpm; monitor weekly.
Week 36–46
On 6 mg for users escalating fully. Phase 2 endpoint zone.
Dosage protocols
Advanced
6 mg
once weekly
Investigational dual GLP-1/glucagon co-agonist.
Beginner
0.3 mg
once weekly
Standard
3.6 mg
once weekly
Titration & adjustment
Phase 2 trial titration: 0.3 mg weekly for 4 weeks, then 0.9 → 1.8 → 2.7 → 3.6 mg in 4-week steps. Maximum studied 6 mg. Monitor resting heart rate weekly because of the glucagon arm. Taper down by one step every 2 weeks when finishing.
Injection timing
Once weekly, fixed weekday. Avoid stimulant-heavy training days within 24 hours of injection because of the glucagon arm.
Side effects & contraindications
- moderateNausea and vomiting during titration — similar pattern to Mazdutide and Retatrutide.
- moderateResting heart rate rises 5–8 bpm at higher doses.
- mildMild jitteriness or anxiety in sensitive users from the glucagon arm.
- severeInvestigational — long-term safety database is small and Phase 3 has not concluded.
Contraindications
- Resting heart rate above 100 bpm or uncontrolled arrhythmia
- Personal or family history of medullary thyroid carcinoma
- Active or recent pancreatitis
- Severe hepatic impairment outside NASH trial protocols
- Pregnancy or active conception attempts
Reconstitution & injection
Research-grade comes as 10 mg lyophilised vials. Reconstitute with 2 ml bacteriostatic water for 5 mg/ml — a 0.3 mg starter dose draws 0.06 ml, or 6 units on a U-100 insulin syringe; 3.6 mg is 0.72 ml (72 units); 6 mg is 1.2 ml. Subcutaneous, once weekly, abdomen or thigh, rotating sites. Fridge stability is 4 weeks once mixed.
Open calculator pre-filledStorage after reconstitution
Refrigerate at 2–8 °C immediately after mixing. Do not freeze. Light-protected. 28 days of stability in BAC water at fridge temperature. The glucagon component is the most thermolabile part of the molecule — a vial left at room temperature overnight is suspect; discard and remix.
Cost & sourcing red flags
Typical price range: Survodutide (Boehringer Ingelheim / Zealand Pharma, BI 456906) is not yet approved; Phase 3 SYNCHRONIZE and LIVERAGE programs are ongoing. Research-grade vials run $90–290 per 10 mg from peptide suppliers, with notable price spread between bulk and verified-COA sources.
Red flags
- 10 mg vials under $80. Survodutide is a 29-amino-acid peptide with a fatty-acid linker for albumin binding; legitimate API cost makes sub-$80 pricing structurally implausible.
- Vendor selling 'survodutide' without a mass-spec COA confirming molecular weight near 4,486 Da. The gray-market substitution pattern for dual-agonists tends to be cheaper monoagonists (semaglutide most often), and HPLC purity alone does not catch this.
- Compounding pharmacy claims to formulate survodutide. There is no legitimate 503A pathway for an unapproved investigational drug, and the published Phase 2 titration schedule is specifically not what most compounders are using.
- Marketing comparing survodutide head-to-head with retatrutide for weight loss outcomes. No direct comparison trial exists; vendors making this claim are inventing it.
- Vials without explicit storage instructions (–20 °C for lyophilized, 2–8 °C reconstituted, protect from light). Dual GLP-1/glucagon peptides degrade faster than pure GLP-1 agonists and unclear storage handling is a quality red flag.
- Suppliers offering 'fast titration kits' that escalate dose in under 8 weeks. The Phase 2 obesity trial's 20-week escalation was already too fast and produced a 24.6% discontinuation rate; aggressive home titration produces severe GI events.
Pricing rots fast and varies by region and supplier. We list no vendors.
Common mistakes
Confusing Survodutide with Retatrutide because both have a glucagon arm.
Better approach: Survodutide is dual (GLP-1 + glucagon); Retatrutide is triple (GIP + GLP-1 + glucagon). The Phase 2 weight-loss numbers are similar, but Retatrutide may have a slightly higher ceiling and is further along in development. If you have a choice, the differentiator is the GIP arm — relevant for appetite and insulin secretion.
Not monitoring heart rate.
Better approach: The glucagon arm raises resting HR in essentially every user at higher doses. Track weekly with the same wearable or stopwatch every time, at the same time of day. Pause escalation if the climb exceeds 15 bpm above baseline or crosses 100 bpm absolute.
Choosing it for general weight loss rather than liver disease.
Better approach: Survodutide's most distinctive data is on liver fibrosis, not weight loss per se. If NASH or NAFLD is your driver, this is a reasonable choice. If you just want weight loss, Tirzepatide is approved with a larger dataset and similar effect size — there is no reason to take on the investigational risk.
Stacking with stimulant pre-workouts.
Better approach: Caffeine, yohimbine, and ephedrine all stack with the glucagon arm's HR effect. For at least 24 hours after each injection, stay off high-stim pre-workouts and intense anaerobic training. The risk is uncomfortable rather than catastrophic but easy to avoid.
Real-world tips
- Track resting heart rate every morning. The glucagon arm is the variable you cannot ignore.
- Inject on an evening followed by a rest day so the HR peak and any GI symptoms are not riding on top of a hard session.
- If you are using it for NASH, baseline a FibroScan or MR elastography before starting. The trial data is on fibrosis improvement, not just ALT — you want the right measurement to track the right outcome.
- Source carefully. Survodutide is research-grade only, and most suppliers are reselling out of Asian wholesalers. Request a current HPLC assay.
- Resistance training matters because the glucagon arm partially preserves energy expenditure but does not preserve lean mass on its own.
What users report
Aggregated from r/Peptides and gray-market dual-agonist forum threads. User base is smaller than for tirzepatide or retatrutide; reports skew toward people experienced with peptides.
Onset: Appetite suppression lands within 48–72 hours of the first 0.3–0.6 mg dose, with a more pronounced thermogenic feel than semaglutide (warmer skin, slight sweating) appearing in week 1.
Common reports
- GI side effects more intense than semaglutide at matched escalation speed — nausea, vomiting, and diarrhea track the 56–66% incidence reported in the Phase 2 trial. Users almost universally recommend slower-than-trial titration.
- Subjective 'metabolic heat' — users describe feeling warmer at rest, sweating more during light activity, occasionally waking up overheated. Attributed by users to the glucagon-receptor arm.
- Liver-area discomfort improvement for users with elevated ALT/AST or fatty liver — consistent with the LIVERAGE Phase 2 MASH results.
- Weight loss in the 12–18% range over 6–9 months among forum users who stick with it, lower than the trial's 16.6% at 76 weeks largely because most users drop out earlier.
- Hypoglycemia is uncommon despite the glucagon component, but some users on a low-carb diet report fasting glucose readings in the 60s — worth monitoring rather than alarming.
- Injection site reactions (small itchy welts, 1–2 cm) more common than with semaglutide; usually resolve in 48 hours.
Where reports diverge from theory: The Phase 3 SYNCHRONIZE-1 result of 16.6% weight loss at 76 weeks used a slower, flexible titration. Gray-market users running the published Phase 2 titration schedule report much worse tolerability than the Phase 3 headline implies. The drug works; the dosing speed in the public protocols is the problem. Users adapting to a 4–6 week hold at each step do significantly better than those following the trial-protocol calendar.
When something else is the better tool
Retatrutide
Use instead when: You want maximum weight-loss effect and have access to either. Retatrutide's Phase 2 numbers are slightly higher, the triple-receptor mechanism is novel, and TRIUMPH Phase 3 is further along. Survodutide's edge is the NASH fibrosis data.
Mazdutide
Use instead when: You specifically want a GLP-1/glucagon dual and are choosing by supply rather than mechanism. The pharmacology is closely matched; the data sets are in different populations.
Tirzepatide plus lifestyle for NAFLD
Use instead when: You want the approved drug, the larger dataset, and acceptable liver outcomes. Tirzepatide has its own NAFLD data and may be enough without taking on investigational risk.
Based on 1 peer-reviewed study
- How does it compare to Retatrutide?
- Both have a glucagon arm. Retatrutide adds a GIP arm, which gives it a marginally higher weight-loss ceiling. Survodutide's distinctive data is on NASH fibrosis. Choose by what you are treating.
- Is the NASH data strong?
- Phase 2 fibrosis improvement is a meaningful endpoint — most NASH trials report ALT or fat fraction, which are softer. About 60% of treated patients met the fibrosis improvement criterion. Phase 3 will confirm or shrink the effect.
- When will it be approved?
- Phase 3 SYNCHRONIZE is enrolling through 2025–2026 with readouts in 2026–2027. Approval, if data holds, is plausible in 2028.
- Is research-grade Survodutide safe to use?
- Same caveats as any unapproved peptide — purity and sterility cannot be verified the way they can for an approved product. Request HPLC and endotoxin assays and treat anything without paperwork as higher-risk.
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