Ace-031, also known as ACVR2B, is a soluble form of activin type IIB receptor, which is an inhibitor of myostatin and other naturally occurring proteins that limit muscle growth. This compound was genetically developed to bind to myostatin before it can attach to its receptor and halt muscle growth. The two Biopharma companies that worked on this compound are Acceleron and Shire.
Human studies
In one human study, overweight females were given a one time dose of 250 milligrams (mg) of Ace 031. As a result, after a month their muscles in the thighs grew over a pound. What’s more, their lean body mass increased 3%, which is quite a result.
However, in another study done on young boys with muscle dystrophy, the test subjects ended up having gum and nose bleeding. Unfortunately, both Shire and Acceleron eventually abandoned their partnership, and since 2013 no further development has been conducted. Since then, you can find Ace-031 being sold as research chemicals on various websites, but no trusted brand has come out selling it yet.
In the different studies that were conducted, subjects experienced a reduction in leptin concentration and boosted adiponectin, which is a ‘good fat’ hormone. Hence, perhaps Ace-031 does really contribute to fat loss. Another study showed an increase in alkaline phosphatase in the blood and reduced collagen telopeptide; this may mean it also helps strengthening the bones.
The half life of Ace-031 is 10-15 days.