ACE-031

Approval status

Not approved anywhere. A phase 2 trial in boys with Duchenne muscular dystrophy was stopped early in 2011 because of nosebleeds and small dilated blood vessels, and development was halted. It is still sold on the black market as a research chemical.¹²⁴⁷⁸

What it’s used or studied for

• Human studies

  Tested in boys with Duchenne muscular dystrophy: trends toward more lean mass and steadier walking distance, but the trial was stopped for safety reasons.¹²

• Human studies

  A single injection increased lean body mass and thigh muscle volume in healthy postmenopausal women.³

• Animal & lab only

  Increased body weight, muscle weight and muscle fiber size in mice.⁶

• Animal & lab only

  Increased lean mass, muscle fiber size and muscle force in marmoset monkeys.⁵

Each label shows how strong the evidence is: an approved use, human studies, animal or lab studies only, or a popular claim with no published studies. Being studied is not the same as being proven safe or effective.

Side effects

In the Duchenne trial, nosebleeds and telangiectasia led to the study being stopped, although no events were rated serious or severe. Later papers also mention gum bleeding, which the trial's posted results do not list, and link these bleeding effects to blocking BMP9, a signal that maintains blood vessels. A single-dose study in healthy women also lowered FSH, a reproductive hormone.¹²³⁴⁵

Cautions

• A doping lab found that black-market "ACE-031" was not ACE-031: 12 of 14 products held the full-length receptor instead, plus many other proteins, and 2 held no receptor at all.⁷
• The published human data are short-term: a single-dose study in healthy women and a trial in boys that was stopped early. There are no long-term safety data.¹³