FibroGen Positioned to Develop First Oral Anemia Therapy for North America

South San Francisco, Calif. - April 28, 2006 - FibroGen, Inc. (FibroGen) today announced it has completed an exclusive licensing agreement with Astellas Pharma Inc. (Astellas) that provides Astellas rights to certain FibroGen hypoxia-inducible factor (HIF) prolyl hydroxylase (PH) inhibitors for development and marketing for the treatment of anemia in Europe, Commonwealth of Independent States (CIS), Middle East, and South Africa. These inhibitors include FG-2216 and FG-4592, currently in human clinical trials. FibroGen retains rights in the rest of the world except in Japan. The Japan rights were licensed previously to Astellas (see FibroGen press release September 24, 2004).

"We are very pleased to broaden our relationship with Astellas, a highly recognized and capable global organization focused on ethical pharmaceutical products generating approximately $8 billion per annum of product sales," said Thomas B. Neff, Chief Executive Officer of FibroGen. "Astellas has the skills, infrastructure, and experience to develop and market oral therapies, which represents a significant asset in helping us to realize the full potential of our HIF-anemia program and to meet our goal of developing novel medicines that provide lower cost, broader benefit, and improved access to anemia therapy."

Astellas has undertaken selected preclinical toxicology studies and phase 1 clinical studies with FG-2216 in Japan and has had access to FibroGen's phase 1 and 2 U.S. and European clinical trial data for FG-2216 and FG-4592. Pursuant to the agreement, Astellas and FibroGen will share in the leadership of the clinical programs for FG-2216 and FG-4592 in both Europe and North America.

"Our confidence and enthusiasm are fortified by the high degree of motivation that Astellas has shown to expand their involvement and specific knowledge of FibroGen's HIF-anemia program through our Japanese collaboration of the past two years," said Mr. Neff.

In Europe, sales of recombinant human erythropoietin (rHuEPO) products for anemia of chronic kidney disease and chemotherapy-induced anemia total approximately $3 billion per annum. Through this collaboration, FibroGen is also positioned to address the larger, multi-million patient market opportunities currently not penetrated and addressed by rHuEPO products, including: chronic kidney disease (CKD) patients who are not yet on dialysis (predialysis) and who are under the care of primary care physicians, patients having cancer-related anemias, patients with anemia associated with congestive heart failure (CHF), age-related anemia patients, and patients with anemia of chronic disease (ACD). ACD is also called anemia of inflammation and is often found in patients with rheumatoid arthritis, inflammatory bowel disease, and Lupus. In preclinical studies, FG-2216 and FG-4592 have been shown to suppress the inhibitory effects of inflammatory cytokines on erythropoiesis, a critical benefit for treating ACD.

"As a result of this agreement, we can focus our resources on completing the development and commercializing oral anemia therapy in North America where the majority of the anemia markets are not yet penetrated," said Mr. Neff. "In addition, FibroGen retains opportunities in selected large emerging market areas in Asia where chronic kidney disease, cancer, aging, and chronic inflammatory disease cause very high rates of anemia in the population. There exists a pressing unmet medical need in these markets due to limited alternatives to transfusion and the prohibitively high cost of the current anemia therapeutics, rHuEPO and intravenous iron. We believe FibroGen's oral therapy is uniquely positioned to address the medical need caused by anemia in these settings."

Under the agreement, Astellas will pay a licensing fee of $300 million to FibroGen upon signing and will further pay development milestones totaling $465 million and share in the costs of a transatlantic development program and patent support. In the event the forecast for sales in Europe, CIS, Middle East, and South Africa is achieved, this agreement offers a potential financial result in excess of $2 billion dollars paid to FibroGen during the 10 to 15 years after 2010. In addition, Astellas will purchase $50 million of FibroGen shares.

Please see the Astellas press release (www.astellas.com) for additional information regarding this collaboration.

About FG-2216 and FG-4592

FG-2216 and FG-4592 are investigational oral anemia therapies designed to restore balance to the body's natural process of erythropoiesis (production of oxygen-carrying red blood cells) through mechanisms including: natural EPO production, suppression of the effects of inflammation, down-regulation of the iron sequestration hormone hepcidin, and an up-regulation of other iron genes, ensuring efficient mobilization and utilization of the body's own iron stores. This contrasts with current rHuEPO therapy, administered by subcutaneous or intravenous injection, which in many cases requires concomitant intravenous iron therapy to improve patient outcome.

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, ischemic disease, 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 FibroGens proprietary cosmetic dermal filler and biomaterials supply business.

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

Contact:
Laura Hansen, Director of Corporate Communications
650-866-7828 or lhansen@fibrogen.com