STUDresearch · Peptide
PEG-IGF-1
Also known as
Pegylated IGF-1 · PEG-IGF-I · PEGylated IGF-I · PEG IGF-1 · PEG-IGF1 · Pegylated recombinant human IGF-1 · PEGylated recombinant human insulin-like growth factor-I · RO5046013 (Roche clinical-research designation) · PEG-rhIGF-I · Long-acting IGF-1 (loose forum shorthand — not LR3)
Community talk. May be wrong. Not medical advice. Not a protocol. Not for human or animal use.
Peptide
Some talk
Systemic
SubQ / IV / IM
Growth factors
Whole-body — people treat this as circulating, not a local pin.
What people say
PEG-IGF-1 is PEGylated full-length IGF-1, discussed for prolonged growth-factor exposure and recovery. The studied construct RO5046013 is not PEG-MGF, LR3, DES or mecasermin; gray-label names often blur these identities.
Doses people talk about
SC clinical, IV infusion and IM preclinical contexts are distinct. The 50 mcg/kg SC twice-daily, four-day human comparator was unmodified rhIGF-I, not PEG-IGF-1.
How it may feel
Legacy accounts describe little acute sensation, possible fullness over days and recovery or physique impressions over weeks. Verified PEG-specific logs are sparse: one opened forum reply names a PEG-IGF/PEG-MGF stack but gives no isolated onset, duration or product verification.
Borrowed LR3 chart amounts~20–50 / 20–100 mcg
These IGF/LR3 amounts are sometimes mislabeled PEG-IGF-1; the record does not establish a matching route/frequency for a verified PEG construct.
Separate PEG-MGF comparison~100–400 mcg
The preserved PEG-MGF comparison uses 2–3 times/week. It is not a PEG-IGF-1 schedule.
Half-life & effect duration
- Half-life in the body
- RO5046013 · clinical constructAbout 140–200 hours — roughly 6–8 days
- Felt duration people report
- Felt durationNo consistent PEG-IGF-specific window reported
- Community timingWorkout or recovery observations over days to weeks
Cycles people discuss
Discussion borrows roughly 3–4-week LR3 cycles or 4–6/4–8-week PEG blocks, with equal or longer breaks. These are conflicting training-block comparisons, not a validated PEG-IGF-1 course or washout.
Timing
Human research used a single SC injection or a 48-hour IV infusion, while community use is inconsistent and often framed as intermittent or less than daily. One forum reply mentioned post-workout use but gave no amount or outcome timeline; no gym schedule is established.
Stacks
LR3, PEG-MGF, GH-axis drugs and recovery peptides appear in stack discussions. These combinations obscure attribution; insulin and other growth-factor combinations carry additional uncertainty.
Watch for
Hypoglycemia (residual pathway risk): PEGylation was designed to reduce acute hypo potential vs multi-dose rhIGF-I, and first-in-man RO5046013 reported no hypoglycemia at studied single ascending doses — residual IGF-pathway glucose disposal risk remains in community caution, especially with insulin, LR3, fasting, or aggressive carb restriction.
Tap a line to jump into the full notes. Research only — may be wrong.
Timing context & sources
Half-life in the body
RO5046013: reported half-life 140–200 hours.
Single-center study in 62 healthy volunteers; SC single-dose and 48-hour IV-infusion arms.
Abstract-level range is not route-stratified and does not certify gray products or a dosing interval.
- Kletzl et al. (2017): first-in-man RO5046013 (opens in a new tab)Abstract Objective, Design, Results and Conclusions; complete abstract retrieved through Europe PMC core API for PMID 28110155 on 2026-09-07.Publisher returned 403 and PubMed rendered inconsistently. Abstract actually read via Europe PMC; no full dose table or route-stratified half-life estimates inspected. Pharmaceutical RO5046013 only.
Felt duration people report
A PEG-IGF-specific felt duration is not established.
One opened forum reply names a PEG-IGF/PEG-MGF stack and predicts workout benefits; legacy notes describe days-to-weeks observations.
No verified product, isolated exposure, timed offset or same-author PEG-IGF outcome update appears in that visible reply.
- Interested in IGF1LR3: PEG-IGF and PEG-MGF comparison (opens in a new tab)2013-10-23 opening post and all visible dated replies, especially HydeMind 2013-10-28 16:07; anonymous 2013-11-05 and blackops79 2013-10-27 replies kept separate.HydeMind names a PEG-IGF/PEG-MGF combination without amount, assay or timed follow-up. Other doses, pumps and appetite comments are about ambiguously named IGF/LR3, not verified RO5046013. Public visible thread only; no acquisition or preparation details adopted.
What people say
- Longer coverage (core lore): Forums and protocol talk frame multi-day systemic exposure vs minutes-to-hours free IGF-1 and vs roughly daily LR3 — the main reason the name gets searched. forum
- Smoother / less pin-frequent narrative: Intermittent dosing is the research concept and the bro pitch relative to daily LR3; actual gray-market practice is inconsistent and poorly logged. forum
- Recovery / training continuity (sparse): Soft recovery and “bounce-back” claims appear, but true PEG-IGF-1 solo logs are thinner than LR3 or PEG-MGF threads. forum
- Size / fullness: Bulk threads sometimes credit “PEG IGF”; stacks (AAS, HGH, surplus, other growth factors) and mislabels make single-agent credit unreliable. anecdote
- Vs LR3 (forum ranking): Longer/smoother systemic coverage than LR3’s ~daily schedule; fewer pins in theory; far less community dose culture and fewer before/after logs. forum
- Vs PEG-MGF (identity + role): PEG-MGF is repair / satellite-cell “early wave” lore; PEG-IGF-1 is longer-acting full IGF-1 signaling lore. Names are routinely swapped in search and vendor titles. forum
- Stack halo problem: Any positive “PEG IGF” log is often co-run with food surplus, progressive overload, HGH/secretagogues, LR3, PEG-MGF, or AAS — attribution is weak. forum
- Anti-catabolic framing: IGF-pathway talk (protein breakdown down, hold size on hard training or cut phases) is borrowed from broader IGF-1 lore more than from dense PEG-IGF-1-specific logs. forum
- Hypoglycemia design claim (clinical): First-in-man RO5046013 work reported no hypoglycemia at studied single ascending doses, and PEGylation was framed as reducing hypo potential vs multi-day rhIGF-I comparator use — design claim, not a free pass for unsupervised gray-market stacks. trial
- Reduced GH-feedback design claim (clinical): Same first-in-man work: rhIGF-I almost completely suppressed GH secretion, whereas RO5046013 caused only a modest GH decrease at the highest IV dose tested. trial
- Animal muscle-injury hook: In a mouse myotoxic-injury model, a single intramuscular PEG-IGF-I injection at day 4 post-injury improved early functional recovery (~27% higher normalized force vs saline) and produced ~13% larger fiber cross-sectional area vs rhIGF-I; systemic application of either variant was not effective in that design. animal
- Prolonged muscle residence (preclinical PK): Same injury model class: after IM, PEG-IGF-I muscle levels were ~4-fold higher at 1 h and ~29-fold higher at 6 h vs rhIGF-I, with detectable muscle levels still elevated at ~48 h when free rhIGF-I was gone — the mechanistic story behind “local IM lasts longer.” animal
- Dystrophy / mild muscle-pathology research backdrop: PEGylated IGF-I has been explored in neuromuscular / dystrophy-adjacent animal programs (benefit sometimes framed as more relevant in milder pathologies) — R&D context, not a physique outcome database. animal
Doses people talk about
- Sparse-chart reality: Unlike LR3 (~20–100 mcg culture) or PEG-MGF (~100–400 mcg, 2–3×/week culture), true PEG-IGF-1 does not have a stable, widely repeated bodybuilding mcg protocol. Many posts titled “PEG IGF” are actually about PEG-MGF or LR3. forum
- Borrowed LR3 bands (common error): Some charts and forum posts copy ~20–50 mcg (or ~20–100 mcg) “IGF” bands onto “PEG-IGF-1” without PEGylated IGF-1 PK support — treat as misapplied LR3 culture, not PEG-IGF-1 consensus. forum
- Frequency concept (research + lore): Intermittent / less-than-daily dosing is the design story because half-life is multi-day in human PK (see half-life field); community practice is inconsistent and often mirrors weekly-or-few-times-weekly PEGylated-peptide habits rather than a published gym schedule. forum
- Not daily-by-default like LR3: Applying a 5–7×/week LR3 pin schedule to a multi-day half-life PEG construct is a common protocol-logic mismatch flagged when people actually separate the molecules. forum
- Source uncertainty: Gray-market “PEG IGF” purity, PEGylation extent, and actual payload identity are unverified in public logs — underdosing, blank vials, and PEG-MGF swaps confound every dose discussion. forum
- Identity-before-mcg rule: Community-savvy threads treat label verification as more important than fine-tuning mcg when the compound is this often misnamed. forum
- Pharma first-in-man context (not a gray protocol): RO5046013 was studied as single ascending subcutaneous injection or intravenous infusion over 48 h in healthy volunteers (n=62 class design); active comparator was unmodified rhIGF-I at 50 μg/kg SC twice daily for 4 days — weight-based clinical-research exposure, not a bodybuilding mcg chart and not transferable as “safe adult research-chem dose.” trial
- Exposure note (clinical): Exposure increased approximately dose-proportionally; half-life ~140–200 h under study conditions — any community “how often” talk should at least acknowledge multi-day residual exposure. trial
- Route in dose talk: SubQ is the systemic/clinical-research default discussion; IM appears in preclinical muscle-injury work and some community site talk; oral is not an established route for these goals. trial
- Weight-based clinical rhIGF-I adjacent (context only): Mecasermin / Increlex is native rhIGF-1 (not PEGylated) weight-based BID SubQ for pediatric severe primary IGFD — not PEG-IGF-1 and not a physique template. trial
- Framing: Community discussion, vendor-chart borrowing, and clinical-research PK context only — not medical advice, not prescriptions, not validated athletic protocols. No peer-reviewed human dose-finding trial establishes a PEG-IGF-1 hypertrophy schedule. forum
How it may feel
- Day of injection: Usually no stimulant-like buzz; awareness is site sting/erythema possibility (also the most frequent AE class in first-in-man SC work) and whether SubQ vs IM was used. forum
- Hours 0–6 glucose watch: Even with PEGylation “lower hypo” marketing, residual IGF-pathway glucose-disposal talk means community caution around fasting, aggressive stacks with insulin/LR3, and low-carb windows — true PEG-IGF-1 symptom density is under-logged. forum
- Days 1–7: Sparse dedicated logs; mild fullness or site awareness more common than dramatic cosmetic change. Many “effects” in this window are training/food confounds. forum
- Weeks 1–2: Early checkpoint on pumps, recovery continuity, soft tissue feel, and any glucose sensations; authenticity and label-identity questions often start here because product confusion is rampant. forum
- Weeks 3–4: If any claimed physique benefit is going to be noticed in gray-market anecdotes, it often lands in this window — still confounded. forum
- Weeks 4–8: Longer continuous gray-market runs are less documented than LR3’s common 3–6 week blocks; public data stays thin. forum
- Post-stop: Very limited public washout logs; longer residual “feel” claims are anecdotal and confounded by half-life lore (multi-day exposure) plus concurrent training. anecdote
- Honesty on timeline depth: There is no rich day-by-day bodybuilding diary culture for verified PEG-IGF-1 the way there is for LR3 — expect sparse, second-hand, and often mislabeled timelines. An opened 2013 Eroids reply by HydeMind recommends PEG-IGF with PEG-MGF, says he takes his IGF post-workout, and predicts stamina/strength benefits from pre-workout use; it gives no PEG-IGF amount, analytical identity or start-to-stop timeline. Other replies in that LR3-titled thread cannot be reassigned to pharmaceutical PEG-IGF-1. forum
Cycles people discuss
- Poorly standardized: Cycle length is much less standardized than LR3’s common ~3–4 week on / multi-week off blocks or PEG-MGF’s ~4–6 (sometimes 4–8) week charts. forum
- Mesocycle tying: When used in physique talk, often imagined for a bulk or hard-training block rather than year-round continuous use — thin evidence base. forum
- Time off: Inconsistent; often mirrored from other IGF analogs (equal or longer off than on) without PEG-IGF-1-specific receptor data in gym users. forum
- Why off-time is still discussed: Broader IGF-family receptor-desensitization lore + cumulative growth-pathway / hypo / organ-growth cautions — pathway caution more than PEG-specific long-run datasets. forum
- Re-runs: Mentioned occasionally on later bulks; no solid long-term gray-market safety base for repeated PEG-IGF-1 cycles. forum
- Exit flags borrowed from IGF family: Recurrent hypo symptoms, progressive unexplained waist/soft-tissue expansion, severe headache/visual symptoms, new concerning growths/lesions — community stop talk, not a complete medical algorithm. forum
- Clinical ≠ research-chem cycles: Early human single-ascending-dose schedules are PK/safety designs, not bodybuilding on/off charts. trial
Timing
- Dosing-logic implication: Multi-day half-life is why infrequent shots get discussed and why daily LR3-style schedules are a poor conceptual copy-paste. forum
- Vs IGF-1 LR3 (forum ranking): LR3 commonly cited ~20–30 h → typically daily (or training-day) pins; PEG-IGF-1 ranked longer systemic. forum
- Vs PEG-MGF: PEG-MGF community half-life talk is often ~48–72 h / multi-day repair-class; PEG-IGF-1 pharma figures are longer still on the circulating-IGF-1 construct — different molecules even when both are “PEG + IGF family.” forum
- Washout / residual exposure: Multi-day half-life means “stopped yesterday” is not the same as “cleared”; stacking decisions right after a pin should respect residual exposure lore. forum
- Free / unbound IGF-1: Minutes-scale circulating half-life for free peptide is the core reason PEGylation and binding-protein biology matter. trial
- Binary/ternary IGFBP complexes (native biology context): Unbound IGF-1 very short; binary complex longer (~tens of minutes class figures in reviews); ternary ALS/IGFBP complex can stretch into many hours — PEGylation is a separate engineered extension strategy beyond native binding-protein carriage. trial
- Pharma PEG-IGF-I (RO5046013): The first-in-man abstract reports a half-life of ~140–200 hours (~6–8 days) in 62 healthy volunteers studied with single SC doses or 48-hour IV infusions. The abstract does not separate that range by route. It is a construct-specific exposure measure, not a gray-vial identity test or felt-duration window. trial
- Dose-proportional exposure (clinical): RO5046013 exposure increased approximately dose-proportionally in the ascending-dose design. trial
- Rodent muscle after IM: PEG-IGF-I showed much higher and longer muscle levels than the same-dose rhIGF-I (elevated at 1 h, 6 h, and still detectable ~48 h in the cited myotoxic-injury PK), supporting prolonged local residence after IM. animal
- Vs free rhIGF-1 / mecasermin practice: Unmodified IGF-1 needs more frequent exposure for sustained levels (clinical BID framing for mecasermin in its approved use) — PEGylation’s pitch is fewer administrations. trial
More on what it is
- Why people search it: “Longer-acting IGF-1” lore — multi-day coverage without daily LR3-style pins — plus muscle-repair and hypertrophy pathway interest. In practice many search hits and forum posts mean PEG-MGF or LR3, not true PEG-IGF-1. forum
- Identity caveat: Catalog “PEG IGF-1 / PEG-IGF” labels may be mis-sold, under-specified PEGylation chemistry, or confused with PEG-MGF. Pharma RO5046013-class material ≠ unverified research-chem powder. forum
- What it is: Insulin-like growth factor-1 covalently modified with polyethylene glycol (PEG) so clearance is slower and circulating exposure lasts much longer than free/unmodified rhIGF-1. Pharma-style PEGylated IGF-I (e.g., Roche RO5046013 class material in published first-in-man work) is not the same thing as a random research-chem vial labeled “PEG IGF.” trial
- Why PEGylation exists: Free/unbound IGF-1 clears in minutes-scale windows; PEGylation is the pharmaceutical strategy to stretch half-life, blunt acute hypoglycemia potential vs multi-dose rhIGF-I, and reduce negative GH feedback relative to unmodified IGF-I in study conditions. trial
- Mechanism talk: Still IGF1R tyrosine-kinase signaling (PI3K/Akt/mTOR protein synthesis, glucose/AA uptake, anti-apoptosis; MAPK/ERK proliferation talk). PEGylation is a PK/delivery modification, not a different receptor target. Insulin-receptor cross-talk and hypo risk remain pathway-level concerns even when design claims lower acute hypo vs rhIGF-I. trial
- Evidence posture: Preclinical muscle-injury and dystrophy-adjacent models plus early human PK/safety (single-ascending-dose healthy-volunteer work) exist; there are no large physique RCTs, no validated bodybuilding dose chart, and far fewer gray-market logs than IGF-1 LR3 or PEG-MGF. trial
- What it is not: Not PEG-MGF (PEGylated mechano growth factor / IGF-1Ec-class splice lore), not IGF-1 LR3 (Long Arg3 analog with reduced IGFBP binding), not IGF-1 DES, not mecasermin / Increlex (native 70-aa rhIGF-1 for pediatric severe primary IGFD), not HGH, not insulin, not an FDA-approved muscle-growth or injury drug. trial
- Research lens: Gray-market dose charts, borrowed LR3 mcg bands, and “fullness” logs are discussion data only — not prescriptions and not proof of product identity. forum
Stacks
- With IGF-1 LR3: Dual “long PEG + daily LR3” logs exist in sparse form; high confound, high mislabel risk, and stacked hypo/growth-pathway load. forum
- With PEG-MGF: “Repair then growth” or “proliferation then differentiation” two-wave lore is usually told as PEG-MGF + LR3; some threads swap PEG-IGF-1 into that slot by name confusion. Timing stories (MGF early post-workout, longer IGF later) are lore, not controlled PEG-IGF-1 trials. forum
- With IGF-1 DES: DES as short local/post-workout spike vs longer systemic PEG — rare true dual logs; identity confusion remains. forum
- GH-axis (HGH, CJC-1295/Ipamorelin, MK-677): Layering exogenous IGF signaling on top of GH-raised endogenous IGF-1 is common stack talk; multi-agent attribution is weak and GH-feedback design claims from PEG-IGF-I do not make unsupervised polypharmacy “clean.” forum
- Insulin: Aggressive nutrient-partitioning stacks appear in broader IGF family talk; hypo risk compounds — especially relevant if someone is actually running LR3 or insulin while thinking they only have “mild PEG IGF.” forum
- AAS bulks: Growth-factor talk layered on steroid cycles; confounds dominate any size claim. forum
- BPC-157 / TB-500 (Wolverine-class recovery stacks): Injury-adjacent forums sometimes put growth factors near healing peptides; causality and product ID both muddy. forum
- Training / food as co-drivers: Progressive overload, surplus calories, peri-workout carbs, and sleep get (and deserve) credit when logs look good. forum
- What not to assume: Vendor “PEG IGF stack packs” rarely prove molecular identity or ratio science — treat as marketing bundles. forum
Storage notes
- No mix instructions here: STUDresearch does not list reconstitution, diluent volumes, or syringe unit charts. People reconstitute many different ways and vial labels differ — that content creates more confusion than clarity. forum
- Storage (general talk only): Unopened research products are usually kept cool, dry, and away from light per the seller label. Anything after first use is product-specific — follow the label, not a universal forum SOP. forum
Watch for
- Edema / water retention: Mild bloating or soft fullness appears in broader IGF-family anecdotes and may be misread as “gains.” forum
- Malignancy / proliferation caution: IGF-pathway stimulation is debated when there is active or prior cancer history; community and medical literature both treat this as a serious theoretical risk domain for growth-factor misuse. forum
- Organ / tissue growth worry (IGF family): Progressive unexplained abdominal expansion, soft-tissue overgrowth talk, and acromegalic-feature lore are borrowed from broader GH/IGF misuse discussions — sparse PEG-IGF-1-specific logs do not erase pathway concern. forum
- Mislabel / product-swap risk: PEG-IGF-1 vs PEG-MGF vs LR3 mix-ups mean users may experience sides (or null effects) of a different molecule than intended; purity and actual mcg unknown on gray market. forum
- Stacking multiplies unknowns: Combining with insulin, multiple IGF analogs, AAS, and GH-axis agents makes attribution and risk assessment unreliable. forum
- Legal / regulatory / sport: Research-chem status varies by jurisdiction; PEGylated IGF-1 is not an approved physique drug. Growth-factor / peptide-hormone classes are prohibited in competitive sport under WADA S2-type frameworks — anti-doping detection exists for related IGF analogs. forum
- No free lunch: Sparse public gray-market logs are not safety proof; physique RCT gap means uncertainty stays high. forum
- Hypoglycemia (residual pathway risk): PEGylation was designed to reduce acute hypo potential vs multi-dose rhIGF-I, and first-in-man RO5046013 reported no hypoglycemia at studied single ascending doses — residual IGF-pathway glucose disposal risk remains in community caution, especially with insulin, LR3, fasting, or aggressive carb restriction. trial
- Injection-site reactions: Erythema after SC was the most frequent adverse event class in first-in-man RO5046013 work; community peptide practice also reports stinging, redness, or irritation at SubQ/IM sites. trial
- GH-axis feedback: Clinical design aimed for less GH suppression than rhIGF-I; highest IV RO5046013 dose still produced a modest GH decrease — unsupervised stacks with GH secretagogues or HGH remain pharmacologically messy. trial
- Headache / neurologic / ophthalmologic flags (rhIGF-1 adjacent): Clinical rhIGF-1 experience includes headaches, papilledema/intracranial hypertension signals, and rare facial-nerve issues in treatment contexts — community stop-flags for severe headache or visual change are borrowed caution, not PEG-specific trial tallies. trial
- Lipohypertrophy / local tissue change: Injection-site lipohypertrophy is documented with rhIGF-1 products; site rotation is standard peptide hygiene talk. trial
Evidence mix
Mostly community / anecdote tags
Full: every bullet (trial + community). Use Scan for a faster bro-science read.