MK-777 (Acetamoren)
MK-777 (Acetamoren) scored 4.5 / 10 (⚖️ Neutral) on the BioHarmony scale as a Research chemical (growth hormone secretagogue, ghrelin receptor agonist).
MK-777, sold as acetamoren, is marketed as a next-generation oral MK-677 analog, yet it has never been tested in one published trial. Every efficacy claim is borrowed from MK-677 (ibutamoren), the studied parent compound. If you want that effect, the parent holds the evidence; the relabel does not.
What is MK-777 (Acetamoren)?
MK-777, sold as acetamoren, is a gray-market research chemical marketed as a next-generation oral ghrelin receptor agonist, positioned as a successor to MK-677 (ibutamoren).
The pitch is that it raises growth hormone and IGF-1 through the same oral secretagogue route as its parent, without the injection burden of peptide GHRH analogs.
The problem sits underneath that pitch. MK-777 has never been tested in a single published study, animal or human, and no independent source has ever characterized the molecule beyond an unaudited vendor data sheet.
Vendor catalogs list a CAS number and a formula that look like an acetylated MK-677 derivative, plausibly a distinct molecule. But no PubChem, ChemSpider, or peer-reviewed record confirms any of it.
The 4.5 score is not a verdict on a proven danger. It reflects a compound whose entire case is borrowed from a related parent, with zero evidence of its own that the borrowing holds.
Terminology
A few terms decide how to read every MK-777 claim. The most important is the gap between a compound that is chemically plausible and one that has been verified, because MK-777 clears the first bar and fails the second.
- Ghrelin receptor (GHS-R1a): The receptor a secretagogue activates to trigger pulsatile growth hormone release. Its natural ligand is ghrelin, identified by Kojima and colleagues 1999.
- Growth hormone secretagogue: Any compound that prompts the body to release its own growth hormone. MK-677 is the studied oral example of the class.
- Acetylated analog: A molecule with an added acetyl group. The vendor formula for MK-777 looks like acetylated MK-677, which would make it distinct but still untested.
- Research chemical: A substance sold for laboratory use and labeled not for human consumption, with no purity oversight.
- Parent-class comparator: Data from MK-677 used to reason about MK-777 by analogy. It describes the parent, not the analog itself.
How do you take MK-777 (Acetamoren)?
Dosing & Protocols
Dosing information is summarized from published research and community reports. This is not a prescribing guide. Consult a healthcare provider before starting any protocol.
Routes & Forms
| Route | Form | Clinical Range | Community Range |
|---|---|---|---|
| Oral | Capsules or liquid (gray-market research chemical) | None established in humans No human study of MK-777 exists, so no clinical dose has ever been set | Vendor-sold 10 to 20 mg per day, unverified and not a validated protocol Vendor packaging sells 10 mg capsules, 20 mg two-capsule packs, and a 20 mg per mL liquid |
Protocols
Vendor packaging (reference only) Anecdotal
- Dose
- 10 to 20 mg oral, per vendor labeling
- Frequency
- Once daily, per vendor labeling
- Duration
- Not established
This is packaging, not a clinical or community-validated protocol. No titration schedule, cycle length, or timing has been independently reported for MK-777.
How this score is calculated →
What are the benefits of MK-777 (Acetamoren)?
Upside contribution: 1.14
| Dimension | Weight | Score | Visual | Weighted |
|---|---|---|---|---|
| Efficacy | 25% | 2.5 | 0.625 | |
| Breadth | 15% | 2.5 | 0.375 | |
| Evidence | 25% | 1.5 | 0.375 | |
| Speed | 10% | 2.8 | 0.280 | |
| Durability | 10% | 1.8 | 0.180 | |
| Bioindividuality | 15% | 2.0 | 0.300 | |
| Total | 2.135 | |||
| Baseline offset (constant) | −1.000 | |||
| Effective upside contribution | 1.135 |
Upside Rationale
The upside for MK-777 is entirely inherited. If its mechanism matches MK-677, it would raise growth hormone and IGF-1, nudging lean mass, appetite, and sleep. That inheritance is the whole of the upside, and every dimension below is capped because not one measurement was ever taken on MK-777 itself.
Efficacy (2.5/5.0): MK-777 has no efficacy data of its own. The score borrows from MK-677, where Nass and colleagues 2008 raised IGF-1 and fat-free mass in healthy older adults over one year.
Efficacy tracks a demonstrated human effect, and there is none for MK-777, so it sits at the midpoint on inherited promise rather than any measured result.
Breadth of Benefits (2.5/5.0): The parent touches several systems: lean mass, appetite, sleep, and bone turnover, seen in Murphy and colleagues 1999 and Copinschi and colleagues 1997.
That breadth is real for MK-677 and hypothetical for MK-777, which inherits the claim without a single endpoint measured in its own name.
Evidence Quality (1.5/5.0): This is the floor of the report. MK-777 has zero compound-specific studies, no PubMed record, no registered trial, and no patent of its own, confirmed by two independent search passes.
The mechanism is assumed from a relabel, and the review literature on the parent class, Sigalos and Pastuszak 2018, still leaves long-term safety open even for MK-677.
Speed of Onset (2.8/5.0): If the mechanism transfers, appetite and sleep shifts appear within days to weeks on MK-677, and body-composition change takes longer. No onset has ever been measured for MK-777.
Durability (1.8/5.0): The effect is a continuous signal that depends on ongoing dosing. Growth hormone and IGF-1 return toward baseline once the compound stops, so the benefit is not retained. No washout data exists for MK-777.
Bioindividuality Upside (2.0/5.0): The oral secretagogue route should apply broadly, which is a point in its favor. But with no human data, there is no responder profile, no predictor, and no variance estimate for MK-777 specifically.
What are the risks & downsides of MK-777 (Acetamoren)?
Downside contribution: 1.70 (safety risks weighted extra)
| Dimension | Weight | Score | Visual | Weighted |
|---|---|---|---|---|
| Safety | 30% | 3.0 | 0.900 | |
| Side effects | 15% | 2.6 | 0.390 | |
| Cost | 5% | 2.8 | 0.140 | |
| Effort | 5% | 1.6 | 0.080 | |
| Opportunity | 5% | 3.0 | 0.150 | |
| Dependency | 15% | 1.8 | 0.270 | |
| Reversibility | 25% | 1.4 | 0.350 | |
| Total | 2.280 | |||
| Harm subtotal × 1.4 | 2.674 | |||
| Opportunity subtotal × 1.0 | 0.370 | |||
| Combined downside | 3.044 | |||
| Baseline offset (constant) | −1.340 | |||
| Effective downside penalty | 1.704 |
Downside Rationale
The dominant downside is opportunity cost. A studied parent, MK-677, already exists, so choosing an uncharacterized relabel means taking on unknown identity and purity risk for no added benefit. The metabolic concern of the class rides alongside it.
Safety Risk (3.0/5.0): MK-777 has no toxicology of its own, so safety is inferred. The parent-class concern is metabolic: MK-677 raises fasting glucose and lowers insulin sensitivity in trials like Nass and colleagues 2008 and Svensson and colleagues 1998.
The growth hormone secretagogue class also carries an unresolved long-term cancer question. Add the total absence of MK-777 safety data and the score stays elevated without reaching a proven-catastrophe floor.
Side Effect Profile (2.6/5.0): Expected effects, borrowed from MK-677, include increased appetite, water retention, and lethargy at higher exposures. These are mechanism-consistent, but no MK-777 complaint rate has ever been recorded.
Financial Cost (2.8/5.0): There is no legitimate channel to price. Only research-chemical vendors sell it, at an ordinary gray-market price for a product with no manufacturing oversight and no guarantee it contains the labeled molecule.
Time and Effort Burden (1.6/5.0): Oral dosing is simple, a small daily step. The burden is weighing and preparing an unverified powder or liquid without an approved product, which adds a small error surface.
Opportunity Cost (3.0/5.0): This is the dimension that decides the score. The studied parent MK-677 already exists and carries the actual human evidence.
Better-evidenced options also exist for lean mass and metabolic goals, such as semaglutide and tirzepatide. Choosing an uncharacterized relabel over any of them means accepting unknown risk for no added benefit.
Dependency and Withdrawal (1.8/5.0): There is no addictive mechanism, craving, or tolerance described for this class. Stopping returns the growth hormone axis toward baseline. The loss of benefit on stopping is a durability matter, not a dependency one.
Reversibility (1.4/5.0): The compound appears to clear on its own, with the hormone signal ending when dosing stops and no permanent structural change described. Clean washout is inferred from the parent, not measured for MK-777.
Is MK-777 (Acetamoren) worth it?
MK-777 is MK-677's reputation wearing a new name. If you want the growth hormone secretagogue effect, the parent has the real evidence and this analog has none, which is why it scores 4.5 and lands below the studied MK-677 at 4.9.
The honest finding is that no science establishes MK-777 works, is safer, or is next-generation relative to MK-677. That positioning is marketing language riding on a better-known, actually-studied molecule.
✅ Best for: Researchers and analysts mapping the gray-market secretagogue space who need a documented example of a relabel with no data of its own.
Writers covering peptide and research-chemical marketing who want the honest evidence state rather than the vendor version. Anyone weighing MK-777 against its parent who needs the comparison spelled out. Not people looking for a compound to take today.
❌ Avoid if: You want a growth hormone secretagogue you can take now, in which case the studied parent MK-677 has the human record MK-777 lacks. You are prone to elevated fasting glucose or insulin resistance, since the parent-class effect raises glucose.
You compete in tested sport, because the class is WADA-banned. You cannot verify a vendor's purity, which for an unlisted molecule is a real sourcing risk.
What is MK-777 (Acetamoren) best for?
The overall BioHarmony score reflects the intervention's primary evidence profile. These subratings are independent assessments per use case.
| Use Case | Score | Summary |
|---|---|---|
| ○ Muscle Growth / Hypertrophy Primary | 3.0 | Inferred from MK-677, which increased fat-free mass without reliable strength gains. No MK-777 data exists, capping this below a tested compound. |
| ○ Body Composition / Fat Loss Primary | 3.0 | Borrowed from the parent, which raised fat-free mass but did not reliably cut fat mass. Zero MK-777-specific measurements exist. |
| ○ Sleep Quality Primary | 3.0 | The parent improved slow-wave and REM sleep in a controlled trial. That is the most defensible inherited claim, but it was never shown for MK-777. |
Frequently Asked Questions
What is MK-777, and is acetamoren the same thing?
MK-777, sold under the name acetamoren, is a gray-market research chemical pitched as a next-generation oral ghrelin receptor agonist and growth hormone secretagogue. Vendor catalogs list a CAS number and a formula, but no PubChem, ChemSpider, or peer-reviewed record confirms them, and no independent lab has characterized it. Acetamoren and MK-777 are two names for the same unverified vendor listing, presented as an oral successor to MK-677.
Is MK-777 different from MK-677?
They are marketed as close cousins, but only one has evidence. MK-777 is presented as an acetylated analog of MK-677, plausibly a distinct molecule, yet with no compound-specific study behind it. MK-677 (ibutamoren) has a real human record: for example Nass and colleagues 2008 showed it raised IGF-1 and fat-free mass in older adults. None of that data was generated with MK-777, so the differences remain on paper rather than in any measured result.
Is there any real data on MK-777?
No. Two independent search passes found no PubMed entry, no ClinicalTrials.gov registration, and no compound-specific patent for MK-777 or acetamoren. Every efficacy figure comes from MK-677 trials such as Copinschi and colleagues 1997 on sleep and Svensson and colleagues 1998 on body composition. Those studied a related parent, not MK-777, so they cannot confirm the analog works, is safer, or does anything at all in a person.
Is MK-777 safe?
Its safety is unknown, because MK-777 has no toxicology of its own. The honest read comes from the parent. Sigalos and Pastuszak 2018 reviewed growth hormone secretagogues and flagged unresolved long-term cancer and mortality questions, and MK-677 trials show a rise in fasting glucose. On top of that sits a sourcing problem: purity testing has found many online products mislabeled, so a buyer cannot confirm the vial even holds the claimed molecule.
Does MK-777 raise blood sugar?
Probably, if the mechanism carries over, and that is a risk rather than a benefit. The parent compound raises fasting glucose: Nass and colleagues 2008 recorded fasting glucose climbing over four weeks in older adults on MK-677, tied to reduced insulin sensitivity. No MK-777 glucose data exists, so anyone using it should track fasting glucose and HbA1c rather than assume the analog behaves differently from its parent.
Can you buy MK-777, and is it legal?
It is sold, but not as a legitimate medicine. MK-777 is neither an approved drug nor a dietary supplement, so vendors ship it as a research chemical labeled not for human consumption. The growth hormone secretagogue class is banned in sport by WADA. There is no pharmaceutical-grade supply, no dose-verified product, and no recourse if a vial contains the wrong molecule or the wrong amount.
How do people dose MK-777?
There is no established human protocol. Vendors sell 10 to 20 mg oral capsules and a liquid, but that is packaging, not a validated dose. No independently reported titration schedule, cycle length, or timing exists for MK-777. For reference, MK-677 human trials used about 25 mg per day orally, shown in work like Murphy and colleagues 1998, and that figure does not transfer to an untested analog with unknown pharmacokinetics.
MK-777 versus MK-677: which should you pick?
If you want the growth hormone secretagogue effect, pick the parent. MK-677 (ibutamoren) has a 25 year human record covering lean mass, sleep, appetite, and its glucose downside, seen across trials like Nass and colleagues 2008 and Murphy and colleagues 1999. MK-777 offers the same marketing with none of the evidence and an unverified identity. There is no rational reason to choose an uncharacterized relabel over the studied MK-677.
What could change MK-777 (Acetamoren)'s score?
BioHarmony scores are living assessments. New research, regulatory changes, or personal context can shift the score up or down. These are the most likely scenarios that would change this intervention's rating.
The single event that would move MK-777 is compound-specific data. Right now the score is held down by evidence at the floor and opportunity cost at the ceiling, so the first real study, in either direction, would move it the most.
| Scenario | Dimension shifts | New Score |
|---|---|---|
| An independent lab verifies the molecule and publishes first animal pharmacology | Evidence 1.5 to 2.2 | 4.8 / 10 ⚖️ Neutral |
| A first human pharmacokinetic and safety study appears | Evidence 1.5 to 2.6, Safety 3.0 to 2.8 | 5.2 / 10 ⚖️ Neutral |
| A trial shows the effect matches MK-677 with a similar profile | Efficacy 2.5 to 3.2, Evidence 1.5 to 3.0 | 5.8 / 10 👍 Worth trying |
| A study finds a worse glucose or safety signal than MK-677 | Safety 3.0 to 3.8, Side effects 2.6 to 3.2 | 3.8 / 10 ⚠️ Caution |
| Purity testing confirms most vendor product is mislabeled | Opportunity 3.0 to 3.4 | 4.2 / 10 ⚠️ Caution |
| Nothing new is published and MK-677 stays the obvious choice | No change, opportunity cost stands | 4.5 / 10 ⚖️ Neutral |
Key Evidence Sources
- Nass et al. 2008, Annals of Internal Medicine: the oral ghrelin mimetic MK-677 raised IGF-1 and fat-free mass in healthy older adults over one year, with fasting glucose climbing.. A randomized 2008 trial of the parent compound MK-677, cited as parent-class comparator data, not MK-777 evidence.
- Svensson et al. 1998, JCEM: two months of oral MK-677 increased GH secretion, fat-free mass, and energy expenditure in obese men.. A 1998 study of the parent compound MK-677 in obese subjects, cited as parent-class comparator data, not MK-777 evidence.
- Murphy et al. 1998, JCEM: oral MK-677 reversed diet-induced protein catabolism during caloric restriction in a controlled trial.. A 1998 catabolism trial of the parent compound MK-677, cited as parent-class comparator, not MK-777 data.
- Murphy et al. 1999, Journal of Bone and Mineral Research: oral MK-677 increased markers of bone turnover in healthy and impaired elderly adults.. A 1999 bone-turnover study of the parent compound MK-677, cited as parent-class comparator, not MK-777 evidence.
- Copinschi et al. 1997, Neuroendocrinology: prolonged oral MK-677 improved slow-wave and REM sleep quality in man.. A 1997 sleep trial of the parent compound MK-677, cited as parent-class comparator, not MK-777 evidence.
- Sigalos and Pastuszak 2018, Sexual Medicine Reviews: a review of growth hormone secretagogues found consistent lean-mass and sleep effects but unresolved long-term cancer and mortality safety.. A 2018 review covering the parent compound MK-677, cited as parent-class comparator, and it flags long-term safety as an open question.
- Kojima et al. 1999, Nature: ghrelin is the growth-hormone-releasing acylated peptide from stomach, the natural ligand of the receptor a secretagogue activates.. A 1999 study establishing the shared receptor biology, cited for mechanistic context on the parent compound class, not as MK-777 evidence.
- Bhasin et al. 2017, JAMA: a chemical composition analysis of substances marketed online as SARMs found only 52 percent matched their label and 39 percent held an unlisted drug.. A 2017 JAMA purity study of unregulated online products, cited as mechanistic context for gray-market sourcing risk, not as parent-compound or MK-777 efficacy data.
What does the evidence say about MK-777 (Acetamoren)?
Evidence on this intervention is summarized across three complementary streams: contemporary clinical research, pre-RCT-era pharmacology and observational use, and the traditional medical systems that documented it first. Convergence across streams signals higher confidence; divergence is surfaced honestly.
Modern Clinical Research
Confidence: Limited
Citations: Nass 2008, Svensson 1998, Copinschi 1997, Sigalos 2018, Bhasin 2017
What to Track If You Try This
These are the data points that matter most while running a 30-day Experiment with this intervention.
How to read this section
- Pre
- Test or score before starting the protocol. Anchors a baseline.
- During
- Track while running the protocol so you can see if anything is changing.
- Post
- Re-test after a full cycle to confirm the change held.
- Up
- The marker should rise. For most positive outcomes, that is a good sign.
- Down
- The marker should fall. For most positive outcomes, that is a good sign.
- Stable
- The marker should hold steady. Big swings in either direction are a yellow flag.
- Watch
- Direction depends on dose, timing, and your baseline. Pay close attention to the trend.
- N/A
- No expected direction. The entry is there to anchor a baseline reading.
- Primary
- The Pulse dimension most likely to shift. Track this first.
- Secondary
- Also relevant, but a smaller or less consistent shift. Track if Primary is unclear.
Bloodwork to Order
Open These Markers In Your Dashboard
- IGF 1 During | Expected Watch
- Fasting Glucose During | Expected Watch
- HbA1c During | Expected Watch
- Fasting Insulin During | Expected Watch
Pulse Dimensions to Watch
- Body During | Expected Watch | Primary
- Energy During | Expected Watch | Secondary
- Sleep During | Expected Watch | Secondary
Subjective Signals (Daily Voice Card)
- Appetite change Scale 1-5 | During | Expected Watch
- Water retention or peripheral edema Scale 1-5 | During | Expected Watch
- Joint or carpal-tunnel-type symptoms Scale 1-5 | During | Expected Watch
Red Flags: Stop and Consult
- New or unexplained mass, lump, or lesion: stop and consult a clinician, given the unresolved long-term IGF-1 and cancer question in the parent-class literature.
- Shortness of breath, rapid weight gain, or swelling: stop and seek care, since fluid retention with cardiac symptoms is a stop-and-consult signal.
- Any product without a verified certificate of analysis: do not take it, because no approved supply of MK-777 exists and identity cannot be confirmed.
Other interventions for Muscle Growth
See all ratings →📊 How BioHarmony scoring works
BioHarmony translates a weighted expected-value calculation into a reader-facing 0–10 score. Tier bands: Skip 0–2.9, Caution 3.0–4.4, Neutral 4.5–5.7, Worth Trying 5.8–6.9, Strong Recommend 7.0–8.7, Top-tier 8.8–10.0.
Harm-type downsides (safety risk, side effects, reversibility, dependency) carry a 1.4× precautionary multiplier. Harm weighs more than benefit. Opportunity-type downsides (financial cost, time/effort, opportunity cost) are subtracted at face value.
Use case subratings are independent assessments of how well the intervention addresses specific health goals. They are not components of the overall score. Each subrating reflects the scorer's judgment based on use-case-specific evidence, safety, and effect sizes.
Every dimension is evaluated on a 1–5 scale, and the baseline (1) is subtracted before weighting. A perfect intervention with zero downsides contributes zero penalty rather than a residual floor, so top-tier scores are actually reachable.
EV = Upside − Downside
EV = 1.135 − 1.704 = -0.569
Formula v2.0 maps EV = 0 to score 5.0. Above neutral, EV = +4.00 reaches 10.0; below neutral, EV = −5.36 reaches 0.0. Both sides use the full 5-point half-scale.
Score = 5 + (-0.569 / 5.36) × 5 = 4.5 / 10
