ACE-031 side effects and risks

Reported side effects

• Nosebleeds: Duchenne: 1/9 at 0.5 mg/kg; 5/9 at 1 mg/kg; 0/6 placebo., moderate. Stop further exposure and contact a clinician; persistent heavy bleeding needs urgent care. (source)
• Visible small blood vessels on skin: Duchenne: 0/9 at 0.5 mg/kg; 5/9 at 1 mg/kg; 0/6 placebo., moderate. A program-stopping vascular signal; seek review if new spots or bleeding occur. (source)
• Injection-site redness: Duchenne: 3/9 at 0.5 mg/kg; 6/9 at 1 mg/kg; 3/6 placebo., mild. Worsening warmth, fever or spreading redness needs assessment. (source)
• Headache: Duchenne: 1/9 at 0.5 mg/kg; 3/9 at 1 mg/kg; 1/6 placebo., mild. Severe headache with weakness, fainting or vision change needs urgent care. (source)
• Pain, warmth and flu-like symptoms after market products: Isolated self reports; rates and actual product identity unknown., moderate. Stop further use and seek care for persistent fever, severe pain or systemic illness. (source)

Stop and get help if

• Nosebleed lasting over 10–15 minutes, heavy bleeding, dizziness or trouble breathing: Stop further exposure and get urgent care; call emergency services for heavy bleeding or fainting.
• Breathing trouble or swelling of the face or tongue after injection: Call emergency services now.
• Fever with worsening painful injection-site swelling: Stop injections and seek urgent assessment.

Who should avoid it

• pregnant: No pregnancy safety data or validated fetal exposure limits; reproductive-age pregnancy was not studied.
• breastfeeding: No breastfeeding or infant-exposure safety data were found.
• tryingToConceive: Activin pathways affect reproduction; human fertility safety and washout remain unknown.
• under18: The pediatric program stopped for vascular safety concerns; community protocols are restricted to adults.
• bleedingDisorder: Nosebleeds and visible small blood vessels stopped the Duchenne study.
• other: A history of hereditary bleeding-vessel disease raises concern with the observed vascular adverse effects.
• other: Severe allergic-reaction history was excluded from the first human trial.
• activeCancer: Healthy-volunteer studies excluded malignancy; safety during active cancer is unknown.
• cancerHistory: Prior malignancy was generally excluded from healthy-volunteer studies.
• surgeryPlanned: Bleeding risk and long exposure matter; the extension excluded planned surgery. No validated washout exists.
• heartCondition: Significant heart disease outside the Duchenne diagnosis was excluded; safety is uncertain.
• kidneyDisease: Significant kidney disease was excluded; no validated dose adjustment exists.
• liverDisease: Significant liver disease was excluded; no validated dose adjustment exists.
• testedAthlete: ACE-031 is prohibited in and out of competition under WADA S4.3.

Interactions

• Anticoagulants: Bleeding risks may add up. This is a precaution from the trial signal, not a measured interaction.
• Antiplatelets and NSAIDs: These drugs can increase bleeding. Combined risk with ACE-031 has not been measured.
• Other activin or myostatin blockers: Overlapping signaling blockade has unknown safety. No human trial validates this stack.
• Erythropoiesis-stimulating drugs: These medicines were excluded in the multiple-dose trial; the clinical interaction is unknown.

Product quality risks

• None of 14 tested market products contained ACE-031; 12 held full-length receptor without the Fc fusion.
• One product contained follistatin and one ipamorelin. The 12 receptor products contained many extra proteins.
• A wrong receptor protein cannot inherit the trial molecule’s dose, activity or 10–15-day half-life.
• No sterility or endotoxin guarantee follows from identity or purity testing.