FibroGen is a pioneer in research on Connective Tissue Growth Factor (CTGF), a multifunctional protein involved in the regulation of cell growth and maintenance and in tissue remodeling. CTGF is responsible for the final common pathology in chronic fibrosis from both TGF-beta - dependent pathways and independent pathways. New research in areas including diabetes, cardiovascular disease, and cancer metastasis establishes CTGF as a pathologic mediator in other fibroproliferative diseases.

CTGF stimulates the production of collagen, fibronectin, and laminin, key components of the extracellular matrix and critical to scar formation as part of the normal wound healing response and tissue repair. However, when these processes go awry, CTGF is overexpressed and causes differentiation of fibroblasts into myofibroblasts, which leads to production of more CTGF. Increased levels of CTGF cause excessive production and accumulation of scar material, resulting in chronic fibrosis, a debilitating condition that can eventually lead to failure of the affected organ.

A growing body of scientific evidence from FibroGen and others implicates CTGF as a central mediator of multiple pathologies underlying common complications of diabetes that affect the kidneys, eyes, and heart. Studies show that CTGF is upregulated by pathogenic stimuli in diabetes including high glucose (e.g., advanced glycation end products, IGF-1), static pressure, hypertension (e.g., angiotensin I, endothelin I) and that CTGF can act independently of TGF-beta to produce fibrosis.

CTGF has been clearly associated with tumor-stromal signaling involved in metastasis and the progression of certain cancers including pancreatic, osteolytic breast cancer, and glioblastoma. FibroGen is developing monoclonal antibodies that block CTGF and inhibit tumor survival, growth, and metastasis.

CTGF is implicated as a causal factor in ocular fibrosis, and high levels of CTGF are correlated with neovascularization in the eye. These processes damage the eye and cause loss of vision. FibroGen is exploring CTGF as a therapeutic target for the treatment of eye diseases including age-related macular degeneration, diabetic macular edema, and glaucoma.