About Duchenne Treatments In The Pipeline Myostatin Inhibition Myostatin, also called GDF-8, is a protein that inhibits muscle growth. It is produced naturally in the body and its production increases with age. Myostatin is required in the body to stop muscles from growing too large. Various induced or natural conditions leading to myostatin deficiency result in increased muscle mass and strength in normal animals and have been shown to treat or prevent a range of muscle wasting conditions. Studies in mouse models of Duchenne show reduced fibrosis and adipose tissue replacement in muscles of mice treated with myostatin inhibitors. Clinical stage Roche BMS-986089: Phase 1/2 trial. Compound originally developed by Bristol-Myers Squibb, now licenced to Roche. This study is currently active and is primarily testing the safety and tolerability of the drug over 24 weeks. The study recruited 40 ambulant participants between ages 5 and 10 with any mutation for DMD. The study design compares patients taking the BMS-986089 to patients taking a placebo. The study is taking place in several sites across the USA and Canada. In August 2018, Pfizer terminated the development of Domagrozumab, a myostatin inhibitor, after the drug did not meet primary efficacy endpoint in a phase 2 clinical trial. The trial was not terminated due to safety. The data gathered from this trial is of high quality and Pfizer hope to use it to help develop new therapies for DMD.