Why compare them?
These records are compared to clarify how their mechanisms, research areas, and evidence maturity differ.
Simple first. Deeper when you want it.
Understand the differences that matter.
See the biggest similarities, differences, strengths, limitations, and unanswered questions first—then open the evidence behind them.
Compound comparison
IGF-1 LR3 vs. Semaglutide
Understand the meaningful overlap, differences, evidence, and unknowns—then go deeper only when you want to.
60-Second Summary
The answer first
Current evidenceComparable evidence base
No direct head-to-head study is represented. This comparison uses separate evidence records that may differ in population, duration, route, dose, and endpoint.
✓ Shared
Shared Similarities
- Both are included in the Relay research library, but their current records answer substantially different questions.
⇄ Different
Biggest Difference
IGF-1 LR3 is distinguished by a modified IGF-1 analogue engineered for low binding-protein affinity. Its direct evidence is laboratory and animal—not the approved human record for native recombinant IGF-1; Semaglutide is distinguished by single GLP-1 receptor agonist with multiple approved injection and tablet products and mature outcomes evidence.
? Unknown
Biggest Unknown
No direct head-to-head study establishes how these compounds compare under the same population, dose, duration, and endpoints.
Key Takeaways
IGF-1 LR3 is distinguished in the current record by a modified IGF-1 analogue engineered for low binding-protein affinity. Its direct evidence is laboratory and animal—not the approved human record for native recombinant IGF-1. Semaglutide is distinguished by single GLP-1 receptor agonist with multiple approved injection and tablet products and mature outcomes evidence. Neither is objectively “better”; the useful question is which evidence record addresses the research question being asked.
Research matrix
Which question has stronger current support?
Research questionStronger current supportExplanation
Human evidenceSemaglutide
IGF-1 LR3: Preclinical evidence. Semaglutide: Mature human evidence.
Regulatory historySemaglutide
IGF-1 LR3: Not FDA approved — preclinical evidence only. Semaglutide: FDA approved for defined product-specific indications.
Mechanistic breadthIGF-1 LR3
More named targets describes mechanistic breadth; it does not establish greater effectiveness.
Direct comparisonUnknown
Separate studies cannot establish comparative superiority.
Deeper when you want it
Explore the evidence and nuance
Best-studied areas and pathway mapSee shared targets, unique pathways, and the research questions attached to each record.
IGF-1 LR3
- Muscle-protein preservation — animal evidence
- Whole-body and organ growth — inconsistent animal evidence
- Glucose lowering — animal risk signal
- Cancer-cell proliferation — laboratory evidence
Semaglutide
- Weight management
- Type 2 diabetes
- Cardiovascular outcomes
- Chronic kidney disease
Pathway and research map
Shared foundation and unique questions
Research confidence by questionCompare regulatory, human-evidence, outcome, and administration records side by side.
Question by question
What each evidence base can actually answer
Regulatory statusEvidence, not a winner
IGF-1 LR3Not FDA approved
Not FDA approved. A peer-reviewed anti-doping paper states that LR3 and related analogues were never approved for human use and are prohibited in sport.
SemaglutideFDA-labeled indications
FDA approved in product-specific formulations for defined weight-management, type 2 diabetes, cardiovascular, kidney, and MASH indications.
Evidence depthEvidence, not a winner
IGF-1 LR3Preclinical only
Multiple animal, laboratory, and analytical studies; no direct human efficacy, safety, pharmacokinetic, or dose-finding study located.
SemaglutideMature Phase 3 + outcomes
Multiple large Phase 3 programs and outcomes trials, including SELECT, FLOW, ESSENCE, STEP TEENS, and the higher-dose STEP UP program.
Weight outcomesEvidence, not a winner
IGF-1 LR3No human evidence
No controlled human weight-loss or body-composition evidence. Animal growth effects were inconsistent and sometimes negative.
SemaglutidePeer-reviewed Phase 3
STEP 1 reported −14.9% mean change at 68 weeks with 2.4 mg versus −2.4% placebo. STEP UP later reported −18.7% with 7.2 mg, −15.6% with 2.4 mg, and −3.9% with placebo at 72 weeks.
Type 2 diabetesEvidence, not a winner
IGF-1 LR3Animal glucose-risk signal
No human diabetes-treatment evidence. Animal studies show stronger and more prolonged glucose lowering than native IGF-I—a risk signal, not a validated therapy.
SemaglutideApproved + extensive trials
Approved injection and oral products have extensive type 2 diabetes evidence. Product names, routes, strengths, and label instructions are not automatically interchangeable.
Obstructive sleep apnoeaEvidence, not a winner
IGF-1 LR3No human evidence
No controlled human obstructive-sleep-apnoea evidence was located.
SemaglutideNo approved indication
No FDA-approved semaglutide indication for obstructive sleep apnoea was identified in the current U.S. labels.
Cardiovascular outcomesEvidence, not a winner
IGF-1 LR3No human outcome evidence
No human cardiovascular-outcome evidence was located. General IGF pathway biology cannot substitute for LR3 outcome trials.
SemaglutideSELECT + labeled uses
SELECT demonstrated fewer major cardiovascular events in adults with established cardiovascular disease and overweight or obesity without diabetes. Other approved product labels cover defined diabetes populations.
Administration and handlingEvidence, not a winner
IGF-1 LR3No validated human protocol
Published LR3 protocols are animal or laboratory exposures. No evidence-based human route, dose, cycle, reconstitution, or monitoring standard was identified.
SemaglutideMultiple product-specific labels
Current FDA labels include weekly subcutaneous injections and daily oral tablets with product-specific administration, switching, and storage instructions. Approved products require no reconstitution.
Comparison limitationsUnderstand what this comparison cannot establish before interpreting separate studies.
Comparable evidence base
- No direct head-to-head trial is represented for this pair.
- Separate studies may use different populations, endpoints, durations, doses, routes, and estimands.
- Results should not be interpreted as comparative superiority or individual guidance.
Current unknowns
Questions the evidence cannot answer yet
- Human pharmacokinetics, glucose risk, long-term proliferative and organ effects, feedback suppression, and real-world product identity.
- Long-term comparative outcomes across newer products and doses, rare events at population scale, and evidence outside studied populations or approved products.
Community Intelligence
Emerging patterns, clearly separated from evidence
IGF-1 LR3
No community experiences yetBe the first account holder to contribute.
Semaglutide
No community experiences yetBe the first account holder to contribute.
Community Intelligence summarizes structured, self-reported experiences. It can reveal patterns and useful research questions, but it cannot prove safety, effectiveness, or cause and effect. Published evidence is always shown separately.