Investors and Media

San Francisco, Calif. - June 15, 2009

FibroGen, Inc. today announced that enrollment has commenced in a phase 2 clinical trial designed to evaluate the efficacy and safety of FG-3019, a fully human monoclonal antibody against connective tissue growth factor (CTGF), in patients with type 2 diabetes and advanced kidney disease.

This phase 2 trial is a randomized, double-blind, placebo-controlled study that will test two dose levels of FG-3019 and is expected to enroll 150 patients with diabetic kidney disease (DKD) across multiple centers. FG-3019 will be administered via infusion every two weeks for a total of six months of treatment. Change in levels of albuminuria from baseline is the primary endpoint of the study.

A completed phase 1 study with FG-3019 in patients with diabetes and microalbuminuria (early-stage kidney disease) showed that administration of FG-3019 led to a rapid decline in albuminuria.^1,2 A similar phase 1 study of FG-3019 in patients with diabetes and more severe macroalbuminuria has completed the treatment phase. Follow-up with patients will be completed by the end of this year. To date, FG-3019 has been well tolerated in all studies.

“New safe and effective therapies for treatment of DKD are urgently needed,” said Dr. Katherine Tuttle, Medical and Scientific Director of the Providence Medical Research Center and Clinical Professor of Medicine at University of Washington School of Medicine. “This is an important clinical study that tests a novel investigational therapy to interfere directly in the fibrotic process. It is hoped that blocking the fibrotic activity of CTGF using FG-3019 will preserve kidney function and significantly improve clinical outcomes for patients with DKD.”

About Diabetic Kidney Disease
Diabetes is a worldwide epidemic: according to the World Health Organization, 171 million people have diabetes. Accompanying this epidemic are reports of dramatic increases in DKD, a progressive deterioration of the kidneys that leads to end-stage renal disease (ESRD), necessitating dialysis or transplant.

During the initial stages of DKD, hyperglycemia and hypertension damage the main structures of the kidney causing hyperfiltration, hypertrophy (increased kidney weight) and elevated excretion of albumin in the urine (albuminuria). A diagnosis of DKD is based in part on the finding of albuminuria.

According to the guidelines of the National Kidney Foundation-Kidney Disease Outcomes Quality Initiative (NKF-KDOQI), microalbuminuria (defined as an albumin to creatinine ratio (ACR) between 30-300 mg/g) is typically associated with normal kidney function, but a greater risk of DKD progression and eventual kidney failure. In the US, approximately 3.4 million patients with diabetes have microalbuminuria.

NFK-KDOQI highlights the diabetic patient population exhibiting even higher elevations of urinary albumin, referred to as macroalbuminuria (ACR >300 mg/g). Macroalbuminuria is associated with progressive decline in kidney function, an increase in systemic blood pressure, and a high risk of kidney failure. Approximately 1.1 million people with diabetes in the US have macroalbuminuria.

About Anti-CTGF Therapy for DKD
In DKD, persistent and excessive scarring of the kidneys leads to ESRD. CTGF has been implicated in this process through its effects on promoting epithelial to mesenchymal transition (EMT), a process whereby injured tubular epithelial cells become mesenchymal cells, which produce excess components of scar tissue.

Selective blockade of CTGF activity using FG-3019 has the potential to be a first-in-class therapy that may provide disease modifying renoprotective benefits resulting in decreased albuminuria and slower decline of renal function.

Results from multiple experimental models of renal disease and DKD support the therapeutic use of FG-3019 in treating DKD. In these nonclinical studies, administration of FG-3019 improved kidney function, ameliorated renal hypertrophy, reduced albuminuria, and decreased fibrosis.

FibroGen's nonclinical research has also demonstrated the potential for FG-3019 to inhibit vascular remodeling and potentially improve cardiac outcomes, an important consideration for treating DKD patients, the majority of whom die from cardiovascular disease before reaching ESRD. In a model of type 1 diabetes, treatment with FG-3019 prevented arterial stiffening, reversed vascular stiffness and microvascular leakage, improved cardiac function, and normalized high blood pressure.

Other Clinical Programs with FG-3019
Another ongoing phase 1 study is evaluating FG-3019 in patients with pancreatic cancer. FibroGen has completed a phase 1 study of FG-3019 in patients with idiopathic pulmonary fibrosis (IPF).

About FibroGen
FibroGen, Inc. is a biotechnology-based drug discovery company using its expertise in the fields of tissue fibrosis, connective tissue growth factor (CTGF), and hypoxia-inducible factor (HIF) biology to discover, develop, and commercialize novel therapeutics for fibrotic disorders, diabetic complications, anemia, conditions associated with tissue damage or injury, cancer, and other areas of unmet medical need. FibroGen also develops and produces recombinant human collagens and gelatins using unique production technology that provides the basis for FibroGen's proprietary cosmetic dermal filler and biomaterials supply business.

For more information about FibroGen, Inc., please visit www.fibrogen.com.

Contact: Laura Hansen, Ph.D., Director, Corporate Communications
415-978-1433 or [email protected]

References

1. Schwartz, S., et al. (2007) Phase 1 study of FG-3019, an anti-CTGF monoclonal antibody, in type 1/2 diabetes mellitus with microalbuminuria. Diabetes Vol. 56, Suppl.1; A151.

2. Adler, S.G., et al. (2006) Dose-escalation phase 1 study of FG-3019, anti-CTGF monoclonal antibody, in patients with type 1/2 diabetes mellitus and microalbuminuria. JASN 17:157A.