Peptide

ACE-031

Also known as

ActRIIB-Fc · ACE031 · Ramatercept (related)

Community talk. May contain inaccuracies. Not medical advice. Not a protocol. Not for human or animal use.

What it is

Identity	An experimental activin-receptor decoy protein discussed for muscle growth and plateaus.
Development	Human development ended after bleeding, blood-vessel and later toxicology concerns.

Notes

A circulating decoy, not a local muscle builder. The engineered protein catches myostatin and related signals that normally limit muscle growth. It acts beyond the injected muscle; a warm or swollen shoulder does not establish targeted growth. UPDATE: ACE-031 Clinical Trials in Duchenne MD (Official context · Accessed 2026-09-30) · Has anyone tried ACE-031? selective and site-specific myostatin inhibitor (Community discussion · Accessed 2026-09-30)

ACE-031 is an experimental protein people discuss for muscle growth and getting past plateaus. Reports range from stronger pumps without strength gains to enthusiastic gains during large stacks. Its clinical development ended after bleeding and blood-vessel concerns.

Bleeding and visible small blood vessels matter. Nosebleeds and tiny widened vessels in the skin contributed to stopping the Duchenne trial. Its abstract did not report serious or severe events; early stopping still prevents a reassuring long-term safety conclusion. ACE-031 treatment of ambulatory boys with Duchenne muscular dystrophy (Official context · Accessed 2026-09-30)

Trials stopped in 2011; development ended in 2013. MDA's updated report says later toxicology findings did not support restarting the program. The earlier hope of resuming trials is superseded by that update. UPDATE: ACE-031 Clinical Trials in Duchenne MD (Official context · Accessed 2026-09-30)

Source context — UPDATE: ACE-031 Clinical Trials in Duchenne MD: Patient organization reporting direct developer statements; historical development context, not current product-quality assurance or personal safety guidance.

Source context — Has anyone tried ACE-031? selective and site-specific myostatin inhibitor: One opening author reports reaction plus recovery; not two people. Unverified vial and unspecified injection depth. ACE-083 reaction in another reply is a different compound. Trial-dose repetitions and identity guesses are not verified user kinetics.

Source context — ACE-031 treatment of ambulatory boys with Duchenne muscular dystrophy: Abstract only. Disease-specific pediatric study; safety concerns caused early stopping. Not a recreational dose/cycle or proof of significant functional benefit.

What people notice

Pump without strength	One author reported more sweating, better pumps and a leaner-looking midsection, without strength gains.
Size and strength claims	Another author reported fuller muscles and early gains while also using several steroids and GH secretagogues.
Local fullness	A triceps-injection report described fullness but suspected inflammation; muscle growth was not verified.

Notes

A better pump can come without added strength. The Eroids opening author reported more workout sweating, a leaner-looking midsection and better pumps, but no strength gain. A pump is temporary fullness during training, not a measurement of new muscle. ACE-031 share experiences? (Personal report · Accessed 2026-09-30)

Muscle size, density and breaking a plateau. An EliteFitness contributor described fuller muscles during extensive drug co-use. That account cannot establish muscle growth from ACE-031 alone. ACE-031: personal reports and commercial reply (Personal report · Accessed 2026-09-30)

Within the first week in one heavily stacked account. The EliteFitness author reported strength and size changes; co-use prevents an isolated ACE-031 onset estimate. ACE-031: personal reports and commercial reply (Personal report · Accessed 2026-09-30)

Stacks obscure both benefit and harm. The positive account included trenbolone, testosterone, drostanolone, oxandrolone, CJC no-DAC and GHRP-2. Their contribution cannot be separated. Suppression and lipid talk around stacks does not make ACE-031 a SARM or establish its own suppression profile.

Local fullness may be a reaction. A Reddit user described fuller triceps after a 1 mg injection but suspected inflammation and could not verify growth. Visible change and useful training improvement are different outcomes. ACE-031: flu symptoms and uncertain local fullness (Personal report · Accessed 2026-09-30)

Source context — ACE-031 share experiences?: Unverified products; ACE-031 injection depth unstated. Commercially oriented forum. Later bilateral IM and four-week rotation comments refer to follistatin/IGF, not ACE-031.

Source context — ACE-031: personal reports and commercial reply: Opening account has extensive steroid/secretagogue co-use; injection depth and product identity unverified. Elvia1023 explicitly advertises a sale; cannot count as independent commercial-free corroboration.

Source context — ACE-031: flu symptoms and uncertain local fullness: Anonymous account; 1 mg injection into triceps, depth not stated. Local fullness may be inflammation. Separate BPC-157/TB-500 shoulder-repair discussion excluded.

Doses people talk about

Separate 2014 accounts	1 mg total over 10 days; separately, 0.5 mg once weekly for four weeks. Neither account specified injection depth.
Shoulder test	100 mcg in each shoulder, 200 mcg that session, followed by pain and flu-like symptoms.
2026 cutting account	1 mg every 4–5 days in a stack; the author had just started and could not judge benefit.
Human trial context	0.02–3 mg/kg once under the skin in healthy postmenopausal women. These body-weight amounts differ from forum vial reports.

Notes

1 mg total over 10 days. The 2014 Eroids author gives a course total, not each injection amount. Exact injection depth was not specified. ACE-031 share experiences? (Personal report · Accessed 2026-09-30)

0.5 mg once weekly for four weeks. A separate EliteFitness account included extensive co-use and did not specify injection depth. It is not a trial-equivalent amount. ACE-031: personal reports and commercial reply (Personal report · Accessed 2026-09-30)

100 mcg in each shoulder: 200 mcg that session. The Reddit author reported a test after lifting, followed by pain and flu-like symptoms. This is a reported exposure, not a tolerable starting amount. Has anyone tried ACE-031? selective and site-specific myostatin inhibitor (Community discussion · Accessed 2026-09-30)

1 mg every 4–5 days in a 2026 cutting stack. The author had just started and could not judge benefit. That suggestion came through a trainer contact, not a tested consumer schedule. Has anyone used a myostatin blocker such as ACE-031? (Community discussion · Accessed 2026-09-30)

0.02–3 mg/kg once under the skin. The healthy-volunteer study randomized 48 postmenopausal women to ACE-031 or placebo. At 3 mg/kg, lean mass rose 3.3% and thigh muscle volume 5.1% by day 29; mean drug half-life was 10–15 days. These are trial measurements, not community doses or timing. Single ascending-dose study of ACE-031 in healthy volunteers (Official context · Accessed 2026-09-30)

Source context — Has anyone used a myostatin blocker such as ACE-031?: Author had just added it to a cutting stack and says it is too early to judge. Suggested amount comes secondhand via a trainer contact. Body-composition baseline is not an ACE-031 outcome. Commercial forum; response displays promotion badges.

Source context — Single ascending-dose study of ACE-031 in healthy volunteers: Abstract only, not full paper. 48 healthy postmenopausal women randomized to drug or placebo; one subcutaneous dose. Not male bodybuilder vial kinetics, repeated-use safety or strength trial.

Half-life, onset & duration

Felt onset	Within a week in one heavily stacked account; no dependable isolated onset for muscle growth.
Felt duration	No reliable single-dose benefit window. One author described warmth for about 24 hours and recovery from soreness/flu-like symptoms by roughly 36 hours.
Half-life	10–15 days in the single-dose human subcutaneous trial; this does not establish the contents or effects of a forum vial.

Notes

Quick symptoms do not establish quick gains. The shoulder-test author described rapid flu-like symptoms and site pain, with no measured muscle benefit. No dependable minutes-or-hours onset for growth emerges from these accounts. Has anyone tried ACE-031? selective and site-specific myostatin inhibitor (Community discussion · Accessed 2026-09-30)

No reliable single-dose benefit window. The EliteFitness author claimed continued growth four weeks after stopping while hormones continued. That cannot isolate ACE-031's duration. ACE-031: personal reports and commercial reply (Personal report · Accessed 2026-09-30)

About 24 hours of warmth; roughly 36 hours to recovery. Those two observations belong to the same shoulder-test author. They describe local warmth and resolution of soreness/flu-like symptoms, not muscle-growth duration or bodily clearance. Has anyone tried ACE-031? selective and site-specific myostatin inhibitor (Community discussion · Accessed 2026-09-30)

The name can hide important differences. Although listed in peptide discussions, the trial drug is a large fusion protein, joining part of a receptor to part of an antibody. Products merely labeled ACE-031 are not established equivalents of that investigational drug. ACE-031 treatment of ambulatory boys with Duchenne muscular dystrophy (Official context · Accessed 2026-09-30)

Cycles people discuss

Reported runs	Ten-day experiments and one four-week weekly run appear. The latter author planned another run without establishing a useful break length.
Time off	Weeks-on/off and steroid-cruise reset claims do not establish a recovery calendar.

Notes

A four-week run, followed by plans for another. That author later planned four weeks, after earlier mentioning six. Neither plan establishes an effective break length. ACE-031: personal reports and commercial reply (Personal report · Accessed 2026-09-30)

Short experiments do not establish a reset. Ten-day experiments and weeks-on/off talk supply no validated recovery calendar. The 2026 Eroids discussion challenges the idea that a steroid cruise reliably resets myostatin after a fixed number of weeks. Has anyone used a myostatin blocker such as ACE-031? (Community discussion · Accessed 2026-09-30)

Stacks

Positive stacked account	Trenbolone, testosterone, drostanolone, oxandrolone, CJC no-DAC and GHRP-2 accompanied ACE-031; their effects cannot be separated.

Notes

None recommended: Historical compound. A checked positive account combined it with trenbolone, testosterone, drostanolone, oxandrolone, CJC no-DAC and GHRP-2; that stack prevents attribution of growth or persistence to ACE-031 alone. [community]

Watch for

Bleeding and vessels	Nosebleeds and tiny widened skin vessels contributed to stopping the Duchenne trial.
Pain and pressure	Reports include injection pain, flu-like symptoms and, in a separate 50 mg-total/10-day account, extreme pumps with alarming head pressure.
Product uncertainty	Unregulated preparations are not verified trial equivalents; redness, itching, lumps and bruising are reported, and long-term safety is uncertain.

Notes

More product can mean a worse experience. A separate Eroids commenter described 50 mg total over ten days and extreme pumps with an alarming head-pressure sensation. That is an adverse subjective account, not a measured diagnosis or an escalation target. ACE-031 share experiences? (Personal report · Accessed 2026-09-30)

Injection reactions and long-term uncertainties remain. Reported cautions include redness, itching, lumps, bruising and uncertain long-term safety of unregulated preparations. Storage depends on the actual product. Severe allergic symptoms, chest pain, new neurological changes or uncontrolled blood pressure or blood sugar require medical care.

Full notes

What ACE-031 actually is

A circulating decoy, not a local muscle builder. The engineered protein catches myostatin and related signals that normally limit muscle growth. It acts beyond the injected muscle; a warm or swollen shoulder does not establish targeted growth. Official context Reddit r/Peptides
The name can hide important differences. Although listed in peptide discussions, the trial drug is a large fusion protein, joining part of a receptor to part of an antibody. Products merely labeled ACE-031 are not established equivalents of that investigational drug. Official context
Injection reports need route context. Some users name shoulders or triceps without stating injection depth. That does not settle intramuscular versus under-the-skin use, and favorable experiences with other peptides do not establish the route for ACE-031. Personal report

Why people look it up

Muscle size, density and breaking a plateau. An EliteFitness contributor described fuller muscles during extensive drug co-use. That account cannot establish muscle growth from ACE-031 alone. Personal report
A better pump can come without added strength. The Eroids opening author reported more workout sweating, a leaner-looking midsection and better pumps, but no strength gain. A pump is temporary fullness during training, not a measurement of new muscle. Personal report
Local fullness may be a reaction. A Reddit user described fuller triceps after a 1 mg injection but suspected inflammation and could not verify growth. Visible change and useful training improvement are different outcomes. Personal report

Doses people discuss

1 mg total over 10 days. The 2014 Eroids author gives a course total, not each injection amount. Exact injection depth was not specified. Personal report
0.5 mg once weekly for four weeks. A separate EliteFitness account included extensive co-use and did not specify injection depth. It is not a trial-equivalent amount. Personal report
100 mcg in each shoulder: 200 mcg that session. The Reddit author reported a test after lifting, followed by pain and flu-like symptoms. This is a reported exposure, not a tolerable starting amount. Reddit r/Peptides
1 mg every 4–5 days in a 2026 cutting stack. The author had just started and could not judge benefit. That suggestion came through a trainer contact, not a tested consumer schedule. Eroids
A proposed 1 mg every other day is not a result. One Reddit question proposes four weeks but misreads a trial figure as 3 mg per dose. The actual figure is per kilogram of body weight; dropping that unit fundamentally changes the comparison. Reddit r/PeptideForum

Half-life: what the circulating numbers mean

10–14 days appears on a community reference page. This is a secondary website figure, not a measurement by users or an identified-vial estimate. It resembles historical trial kinetics, discussed separately below. Community guide
A 24-hour clearance chart conflicts with its own text. The Longevity Archive says 10–15 days but draws a chart assuming one day. That chart cannot establish a four-to-five-day clearance window. Half-life means losing half the drug, not losing half a pump. Community guide

When people notice something

Within the first week in one heavily stacked account. The EliteFitness author reported strength and size changes; co-use prevents an isolated ACE-031 onset estimate. Personal report
Quick symptoms do not establish quick gains. The shoulder-test author described rapid flu-like symptoms and site pain, with no measured muscle benefit. No dependable minutes-or-hours onset for growth emerges from these accounts. Reddit r/Peptides

How long changes or reactions last

No reliable single-dose benefit window. The EliteFitness author claimed continued growth four weeks after stopping while hormones continued. That cannot isolate ACE-031's duration. Personal report
About 24 hours of warmth; roughly 36 hours to recovery. Those two observations belong to the same shoulder-test author. They describe local warmth and resolution of soreness/flu-like symptoms, not muscle-growth duration or bodily clearance. Reddit r/Peptides

Courses and breaks in the reports

A four-week run, followed by plans for another. That author later planned four weeks, after earlier mentioning six. Neither plan establishes an effective break length. Personal report
Short experiments do not establish a reset. Ten-day experiments and weeks-on/off talk supply no validated recovery calendar. The 2026 Eroids discussion challenges the idea that a steroid cruise reliably resets myostatin after a fixed number of weeks. Eroids Community

Good to know

Bleeding and visible small blood vessels matter. Nosebleeds and tiny widened vessels in the skin contributed to stopping the Duchenne trial. Its abstract did not report serious or severe events; early stopping still prevents a reassuring long-term safety conclusion. Official context
Trials stopped in 2011; development ended in 2013. MDA's updated report says later toxicology findings did not support restarting the program. The earlier hope of resuming trials is superseded by that update. Official context
More product can mean a worse experience. A separate Eroids commenter described 50 mg total over ten days and extreme pumps with an alarming head-pressure sensation. That is an adverse subjective account, not a measured diagnosis or an escalation target. Personal report
Stacks obscure both benefit and harm. The positive account included trenbolone, testosterone, drostanolone, oxandrolone, CJC no-DAC and GHRP-2. Their contribution cannot be separated. Suppression and lipid talk around stacks does not make ACE-031 a SARM or establish its own suppression profile. Community
Injection reactions and long-term uncertainties remain. Reported cautions include redness, itching, lumps, bruising and uncertain long-term safety of unregulated preparations. Storage depends on the actual product. Severe allergic symptoms, chest pain, new neurological changes or uncontrolled blood pressure or blood sugar require medical care. Community

Human research, kept separate from user reports

0.02–3 mg/kg once under the skin. The healthy-volunteer study randomized 48 postmenopausal women to ACE-031 or placebo. At 3 mg/kg, lean mass rose 3.3% and thigh muscle volume 5.1% by day 29; mean drug half-life was 10–15 days. These are trial measurements, not community doses or timing. Official context
Muscle measurements are not proven strength or bone benefits. The Duchenne study used injections every 2–4 weeks and reported trends in lean mass, fat, bone density and walking. Its walking result was not statistically significant, and safety concerns ended the study. Official context

What the community experience adds

Enthusiasm and seller influence can share a thread. A reply praised 1 mg every two weeks while advertising a sale. It supplies no independent confirmation of the opening account. Personal report
People want evidence beyond a convincing label. An IronMag questioner specifically sought reports from people who were not selling it; the disclosed representative replying admitted no ACE-031 experience. Authenticity is a concern, not something a forum testimonial can resolve. IronMag
Cost keeps trial comparisons unresolved. The 2026 Eroids author wondered whether the smaller amount was worthwhile because trial-scale use seemed unaffordable. That question does not prove either inactivity or effectiveness. Cutting, other drugs and hydration also complicate body-composition comparisons. Eroids
Symptoms cannot identify the molecule. Reddit replies disputed whether a painful, flu-like reaction meant the vial contained something else. No product analysis was supplied. The author's later suggestion of inflammation is plausible interpretation, not confirmed identity or a reason to repeat the exposure. Reddit r/Peptides