MK-677 (Ibutamoren) vs CJC-1295 (Mod GRF 1-29)
Independent, side-by-side comparison of MK-677 (Ibutamoren) and CJC-1295 (Mod GRF 1-29): mechanism, half-life, dose range, safety profile, and live vendor pricing. Updated continuously as new research and listings land.
Live price snapshot
MK-677 (Ibutamoren)
CJC-1295 (Mod GRF 1-29)
MK-677 (Ibutamoren)
MK-677 (also called Ibutamoren or Nutrobal) is an orally-active, non-peptide ghrelin receptor (GHS-R1a) agonist developed by Merck Research Laboratories in the 1990s. Unlike Ipamorelin, GHRP-2, or hexarelin — all of…
Live lowest price: $74.99 across 1 vendor
Full MK-677 (Ibutamoren) profileCJC-1295 (Mod GRF 1-29)
CJC-1295 without DAC (also called Modified GRF 1-29 or MOD-GRF 1-29) is a 30-amino-acid analog of the first 29 residues of endogenous Growth Hormone Releasing Hormone (GHRH), with four strategic substitutions (D-Ala┬▓…
Live lowest price: $29.00 across 5 vendors
Full CJC-1295 (Mod GRF 1-29) profileSide-by-side comparison
| Attribute | MK-677 (Ibutamoren) | CJC-1295 (Mod GRF 1-29) |
|---|---|---|
| Category | Growth Hormone / IGF-1 Axis | Growth Hormone / IGF-1 Axis |
| Research Stage | Phase II | Phase 2 (clinical development discontinued) |
| Mechanism of Action | MK-677 is a small-molecule full agonist at the growth hormone secretagogue receptor 1a (GHS-R1a) — the same receptor activated by endogenous ghrelin and the peptide GHS compounds (Ipamorelin, GHRP-2, GHRP-6, hexarelin). What distinguishes MK-677 is its… | MOD-GRF 1-29 exerts its effect through a single, well-characterized receptor: the GHRH receptor (GHRHR) on anterior-pituitary somatotroph cells. The signaling cascade is the same as endogenous GHRH; the difference is pharmacokinetics. 1. GHRH receptor agonism… |
| Half-Life | ~24 hours (oral) | ~30 minutes (without DAC / MOD-GRF 1-29); 8+ days (with DAC, due to covalent albumin binding) |
| Typical Dose Range | 10,000–25,000 mcg (10–25 mg) oral daily | Without DAC: 100-300 mcg subcutaneous 1-3x daily (typically pre-bedtime); With DAC: 1000-2000 mcg subcutaneous once weekly |
| Dosing Frequency | Once daily, typically at bedtime | 1–3 times daily, typically before bed and/or upon waking |
| Administration | oral | Subcutaneous |
| Side Effects | MK-677 has the most pronounced side-effect profile of any GHS compound — specifically because its 24-hour half-life produces sustained rather than pulsatile receptor engagement. Users should expect all of the side effects listed below at some frequency. Common… | Expected / benign - Injection-site reaction — mild redness, itching, small bump; 24-48 hour resolution - Facial flushing / warmth 15-30 min post-injection (histamine release from GHRH action); typically diminishes after week 1-2 - Mild nausea in first week at… |
| Molecular Weight | 528.7 Da | 3367.9 Da |
| Common Vial Sizes | 25mg capsules, 30mL liquid | 2mg, 5mg |
Price tracking
Price History
2 data points- VANDL Labs
- Ion Peptide
MK-677 (Ibutamoren) — potential benefits
- Increased IGF-1 (~80-100% over baseline at steady state)
- Improved slow-wave sleep architecture
- Lean body mass increase (demonstrated in 2-year older adult trial)
- Improved connective tissue / wound / bone repair
- Once-daily oral convenience (no injections)
- Appetite stimulation (benefit for underweight or hard-gainer populations)
- Enhanced recovery between training sessions
- Potential bone mineral density improvement
CJC-1295 (Mod GRF 1-29) — potential benefits
- Preserves physiologic pulsatile GH secretion
- Stimulates endogenous GH release (2-5x baseline per pulse)
- 3-5x greater GH response when stacked with ipamorelin
- Modest IGF-1 elevation (1.5-2x baseline)
- Improved sleep depth and architecture
- Enhanced recovery from exercise and injury
- Body composition improvements (lean mass preservation, modest fat loss)
- Lower desensitization risk vs CJC-1295 with DAC
Frequently asked
What's the difference between MK-677 (Ibutamoren) and CJC-1295 (Mod GRF 1-29)?
MK-677 (Ibutamoren) is a growth hormone / igf-1 axis that mk-677 is a small-molecule full agonist at the growth hormone secretagogue receptor 1a (ghs-r1a) — the same receptor activated by endogenous ghrelin and the peptide ghs compounds…. CJC-1295 (Mod GRF 1-29) is a growth hormone / igf-1 axis that mod-grf 1-29 exerts its effect through a single, well-characterized receptor: the ghrh receptor (ghrhr) on anterior-pituitary somatotroph cells. the signaling cascade is the same…. The two differ in mechanism, half-life (~24 hours (oral) vs ~30 minutes (without DAC / MOD-GRF 1-29); 8+ days (with DAC, due to covalent albumin binding)), and typical dose range.
Which has the longer half-life, MK-677 (Ibutamoren) or CJC-1295 (Mod GRF 1-29)?
MK-677 (Ibutamoren) has a half-life of ~24 hours (oral). CJC-1295 (Mod GRF 1-29) has a half-life of ~30 minutes (without DAC / MOD-GRF 1-29); 8+ days (with DAC, due to covalent albumin binding). Longer half-lives generally mean less frequent dosing but slower on/off kinetics.
Which is cheaper, MK-677 (Ibutamoren) or CJC-1295 (Mod GRF 1-29)?
Current lowest live price on BodyHackGuide: MK-677 (Ibutamoren) from $74.99, CJC-1295 (Mod GRF 1-29) from $29.00. Prices are pulled from the vendor listings tracked on BHG and change frequently — see the compare tables on each compound page for the current set of offers.
Can you stack MK-677 (Ibutamoren) and CJC-1295 (Mod GRF 1-29)?
Stacking depends on mechanism overlap, safety profile, and goals. MK-677 (Ibutamoren) and CJC-1295 (Mod GRF 1-29) should only be stacked after reviewing each compound's individual protocol page, side effect profile, and any published interaction data. Use the BodyHackGuide stack builder for a structured review before combining research compounds.
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Research use only. BodyHackGuide is an independent research reference. The compounds discussed on this page are not approved by the FDA for human consumption and are sold strictly for laboratory research. Prices shown are pulled from vendor listings tracked on BHG and are subject to change. We earn an affiliate commission on some outbound clicks — this never affects the data or pricing shown. See editorial standards and affiliate disclosure.