Side-by-side · Research reference

IGF-1 LR3vsSurvodutide

Side-by-side comparison across mechanism, dosage, evidence, side effects, administration, and stack synergies. Citations on every claim where available.

AAnimal-StrongHUMAN-REVIEWED10/58 cited

BPhase 3HUMAN-REVIEWED25/54 cited

IGF-1 LR3

IGF-1 Analogue · Research

3–10×Potency vs IGF-I

Low IGFBPBinding affinity

ResearchStatus

Research only · SQ typical in animal models

Survodutide

GLP-1/Glucagon Dual Agonist · Phase 3

Once weeklyFrequency

Phase 3Development stageRubino 2026

GLP-1/GCGRDual targetZimmermann 2026

SQ · Once Weekly

01Mechanism of Action

Parameter

IGF-1 LR3

Survodutide

Primary target

IGF-1 receptor (IGF-1R)McTavish 2009

GLP-1 receptor and glucagon receptor (GCGR)Yathindra 2026 Zimmermann 2026

Pathway

IGF-1R → IRS-1 → PI3K/Akt → Cell proliferation, protein synthesis, anti-apoptosisMuhlbradt 2009

Central: CVOs → hypothalamic appetite regulation. Peripheral: GLP-1R → incretin effect; GCGR → hepatic lipid metabolism, energy expenditureZimmermann 2026 Long 2026

Downstream effect

Enhanced cell proliferation, muscle anabolism, inhibition of apoptosis, increased telomerase activity

Decreased energy intake, increased energy expenditure, improved glucose homeostasis, hepatic fat reductionZimmermann 2026 Yathindra 2026

Feedback intact?

No — exogenous IGF analogue bypasses GH-mediated regulation

—

Origin

Synthetic 83-AA analogue: 13-AA N-terminal extension + Arg substitution at position 3

—

Antibody development

—

02Dosage Protocols

Parameter

IGF-1 LR3

Survodutide

Research dose (animal models)

Variable by protocol and species

In vivo murine atherosclerosis studies used sustained delivery.

—

In vitro typical concentration

10–1000 ng/mLThomas 2007

Dose-dependent effects on follicle growth and estradiol production.

—

Half-maximal stimulation

0.6 nM LR3 vs 1.5 nM native IGF-1Price 2004

2.5-fold greater potency in lung fibroblast proliferation.

—

Evidence basis

Animal / in vitro only

Phase 2 RCT (obesity) · Phase 3 ongoing

Human use

Not FDA-approved; no published human trials

—

Standard dose

—

Not yet disclosed (Phase 3 ongoing)

SYNCHRONIZE Phase 3 program underway.Rubino 2026

Frequency

—

Once weekly

Route

—

SubcutaneousYathindra 2026

Phase 2 findings

—

Significant weight loss and metabolic marker improvementYathindra 2026

MASH indication

—

Under investigation for MASH-cirrhosisPatil 2026 Andonie 2026

03Metabolic / Fat Loss Evidence

Parameter

IGF-1 LR3

Survodutide

Mechanism

IGF-1R activation → lipolytic signaling; secondary to anabolic effects

—

Direct lipolytic evidence

Minimal — primarily anabolic/anti-apoptotic in literature

—

Atherosclerotic plaque effects

Reduced stenosis and core size in ApoE-KO micevon 2011

Plaque stabilization via vSMC phenotype modulation, not direct fat loss.

—

Human data

None published

—

Primary fat target

—

Total body weight, visceral adipose tissue

Weight loss mechanism

—

Dual action: decreased energy intake + increased energy expenditureZimmermann 2026

Phase 2 efficacy

—

Significant weight loss demonstrated

Specific percentage not disclosed in abstracts.

Metabolic markers

—

Improvements in ALT, AST, LDL levels; significant ALT reduction (MD -22.10 vs placebo)Yathindra 2026 Abulehia 2026 Andonie 2026

MRI-PDFF reduction

—

Hepatic fat reduction demonstrated in MASH trialsAndonie 2026

Network meta-analysis

—

Favorable efficacy profile vs other glucagon receptor agonists

Hepatic requirement

—

Hepatic GCGR required for maximal weight loss and metabolic effectsLong 2026

Energy expenditure

—

Increased energy expenditure contributes to weight lossZimmermann 2026

Comparative efficacy

—

Network meta-analysis shows competitive efficacy in GRA class

04Side Effects & Safety

Parameter

IGF-1 LR3

Survodutide

Hypoglycemia risk

Theoretical — IGF-1 analogues can lower blood glucose

—

Excessive cell proliferation

Mitogenic signaling; theoretical tumor promotion risk

—

Telomerase activation

2–10-fold increase in prostate cancer cells (PC-3, DU-145, LAPC-4)Wetterau 2003

Critically involved in cancer cell immortalization.

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Oocyte degeneration

Increased oocyte degeneration at high doses (≥1000 ng/mL) in bovine folliclesThomas 2007

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Unregulated anabolism

Bypasses physiological GH/IGF-1 feedback; no pulsatility control

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Unknown human safety profile

No published human trials; safety data absent

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GI symptoms

—

Diarrhea, nausea, fatigue — class effect of GLP-1 agonists

Safety profile

—

Network meta-analysis: comparable safety to other GRAs

Serious adverse events

—

Monitored in Phase 2/3; no unique safety signals reported

Detailed SAE data pending Phase 3 completion.

Injection site reactions

—

Expected with subcutaneous administration

Glucagon-related effects

—

Potential for tachycardia, increased blood pressure — theoretical glucagon effect

Absolute Contraindications

IGF-1 LR3

·Active malignancy or history of cancer
·Not approved for human use

Survodutide

·Personal or family history of medullary thyroid carcinoma (class effect)
·Multiple endocrine neoplasia syndrome type 2

Relative Contraindications

IGF-1 LR3

·Diabetes or glucose intolerance
·Family history of cancer

Survodutide

·Severe GI disease (inflammatory bowel disease, gastroparesis)
·History of pancreatitis
·Cardiovascular disease (monitor closely for glucagon effects)

05Administration Protocol

Parameter

IGF-1 LR3

Survodutide

1. Research use only

IGF-1 LR3 is not FDA-approved for human use. All administration data derives from animal or in vitro studies.

Specific reconstitution protocol not yet publicly disclosed. Follow manufacturer instructions upon approval.

2. Typical research route

Subcutaneous or intraperitoneal injection in animal models. In vitro: added directly to culture medium at concentrations of 10–1000 ng/mL.Thomas 2007

Subcutaneous — abdomen, thigh, or upper arm. Rotate sites weekly to minimize injection site reactions.

3. Reconstitution (research)

Lyophilised powder reconstituted in sterile water or buffered saline per manufacturer protocol. Store at 2–8 °C after reconstitution.

Once weekly, same day each week. Can be administered at any time of day, with or without meals.

4. Stability

Enhanced stability vs native IGF-1 due to reduced IGFBP binding; exact half-life in vivo not fully characterized in humans.

Store refrigerated (2–8 °C) until use. Do not freeze. Protect from light. Specific reconstituted storage duration pending labeling.

5. Needle

—

Subcutaneous injection with appropriate gauge needle (typically 27–31G). Use sterile technique.

06Stack Synergy

IGF-1 LR3

+ GHRP-6

Multi-pathway

View GHRP-6 →

GHRP-6 stimulates endogenous GH release, which drives hepatic IGF-1 synthesis. IGF-1 LR3 provides exogenous, IGFBP-resistant IGF signaling. Combining upstream GH stimulation with downstream IGF receptor activation creates a dual-pathway anabolic effect. However, this bypasses natural feedback and carries compounded mitogenic risk.

GHRP-6: 100–200 mcg SQ · 2–3× daily
IGF-1 LR3: Research doses variable · post-workout typical in animal models
Note: Research context only — no human protocols exist
Primary benefit: Theoretical maximal anabolic signaling (GH + IGF axes)

+ Ipamorelin

Multi-pathway

View Ipamorelin →

Ipamorelin (selective GHRP) stimulates pulsatile GH release without cortisol/prolactin elevation. IGF-1 LR3 directly activates IGF-1R independent of GH. This stack targets both upstream (GH secretion) and downstream (IGF receptor) nodes but eliminates physiological feedback, raising safety concerns around unchecked proliferation.

Ipamorelin: 200–300 mcg SQ · evening
IGF-1 LR3: Research doses only · timing variable
Caution: No human data; animal/in vitro only
Primary benefit: Dual-axis anabolic signaling (theoretical)

Survodutide

— no documented stacks