The US FDA has completed its review of FibroGen’s investigational new drug application for the study of FG-3019 in patients with Duchenne muscular dystrophy (DMD) and approved it for clinical study.

FG-3019 is a fully human monoclonal antibody that inhibits the activity of connective tissue growth factor (CTGF), a common mediator of fibrotic disease. FG-3019 is currently in Phase 2 clinical studies for idiopathic pulmonary fibrosis and pancreatic cancer.

The IND enables FibroGen to initiate a multi-site Phase 2 trial exploring FG-3019 for the treatment of DMD in non-ambulatory patients, scheduled to begin later this year. This submission is the culmination of nearly 10 years of research by FibroGen and its collaborators to understand the role of CTGF in DMD. Data from these investigations, including the testing of FG-3019 in preclinical models of DMD, have appeared in several peer reviewed publications.

In DMD, muscle cells are damaged due to the absence of the dystrophin protein complex necessary for normal muscle fiber function. Absence of dystrophin leads to muscle damage, inflammation, fibrosis, and progressive dysfunction and weakness in the muscles of DMD patients. The extent of diminished muscle function directly correlates with the extent of intra-muscular fibrosis.

The rationale for FG-3019 in DMD is based on data that show CTGF reduces the ability of damaged muscle cells to repair themselves and promotes muscle fibrosis. In preclinical studies, FG-3019 reduced muscle fibrosis and significantly improved muscle function. Separately, in clinical trials of another fibrotic condition, idiopathic pulmonary fibrosis, FG-3019 was shown to reverse fibrosis in a significant proportion of patients.

“We believe FG-3019 may have the ability to not only stabilize but also reverse the progression of fibrosis in disease,” stated Frank H. Valone, MD, Chief Medical Officer of FibroGen.