ACE-031 results: what to expect and when

An experimental muscle-growth protein whose Duchenne program stopped over bleeding concerns.

Also called: Ramatercept, ACE031, ActRIIB-IgG1, ActRIIB-Fc.

Myostatin pathway · Soluble activin receptor IIB–IgG1 Fc fusion protein.

Four registrations: two published randomized trials, a 70-person multiple-dose trial and an 11-person extension. The last two lack posted results; extension participants overlap the Duchenne trial.

Key studies

  • Single dose in 48 women: At 3 mg/kg, lean mass rose 3.3% and thigh volume 5.1% at day 29. (source)
  • Multiple doses in 70 women: Completed multiple-dose study has no posted results or located full publication. (source)
  • Duchenne randomized trial: Nosebleeds and visible small blood vessels prompted stopping after two dose regimens. (source)
  • Duchenne extension, stopped early: Extension stopped on preliminary safety data; no results were posted. (source)
  • What the receptor binds: The receptor binds several growth signals; it is not a muscle-only myostatin blocker. (source)
  • Marmoset muscle study: Muscle changes in primates do not override the human vascular safety signal. (source)

Related to ACE-031

Sources

Sources checked: 2026-10-18.

Information only, not medical advice. Peptifacts does not sell anything and does not link to sellers.