FibroGen Announces Completion of Patient Enrollment in ZEPHYRUS-2, a Phase 3 Clinical Study of Pamrevlumab in Idiopathic Pulmonary Fibrosis

- 372 IPF Patients Enrolled -
- Topline Data Anticipated Mid-2024 -

SAN FRANCISCO, April 03, 2023 (GLOBE NEWSWIRE) -- FibroGen, Inc. (NASDAQ: FGEN) today announced the completion of patient enrollment for ZEPHYRUS-2, a Phase 3 clinical study of pamrevlumab in patients with idiopathic pulmonary fibrosis (IPF), a chronic, progressive, and fatal lung disease.

“We are pleased to announce the completion of enrollment for our second Phase 3 study of pamrevlumab in IPF,” said Mark Eisner, M.D, M.P.H, Chief Medical Officer, FibroGen. “The ZEPHYRUS program consists of two phase 3 clinical trials that will evaluate the ability of pamrevlumab to attenuate fibrosis and lung function decline in patients with idiopathic pulmonary fibrosis. IPF is a fatal progressive disease, and patients need new treatment options to improve their clinical outcomes.”

Three hundred seventy-two (372) patients have been enrolled into ZEPHYRUS-2, a randomized, double-blind, placebo-controlled, multi-center Phase 3 trial designed to evaluate the efficacy and safety of pamrevlumab in patients with IPF. The primary endpoint of the study is the change from baseline in forced vital capacity (FVC) at 48 weeks. Top-line data from ZEPHYRUS-2 is anticipated in mid-2024. For more information about ZEPHYRUS-2, please visit (NCT04419558).

The first study in our pamrevlumab IPF Phase 3 clinical development program is ZEPHYRUS-1 (N=356). Like ZEPHYRUS-2, ZEPHYRUS-1 is a randomized, double-blind, placebo-controlled, multi-center Phase 3 trial with a primary endpoint of change from baseline in forced vital capacity (FVC). Top-line data from ZEPHYRUS-1 is anticipated in mid-2023. For more information about ZEPHYRUS-1, please visit (NCT03955146).

About Pamrevlumab
Pamrevlumab is a potential first-in-class antibody being developed by FibroGen to inhibit the activity of connective tissue growth factor (CTGF), a common factor in fibrotic and proliferative disorders characterized by persistent and excessive scarring that can lead to organ dysfunction and failure. Pamrevlumab is in Phase 3 clinical development for the treatment of idiopathic pulmonary fibrosis (IPF), locally advanced unresectable pancreatic cancer (LAPC), and Duchenne muscular dystrophy (DMD), and in Phase 2/3 for the treatment of metastatic pancreatic cancer. The U.S. Food and Drug Administration has granted Orphan Drug Designation, and Fast Track designation to pamrevlumab for the treatment of patients with IPF, DMD, and LAPC. The U.S. Food and Drug Administration has also granted Rare Pediatric Disease Designation to pamrevlumab for the treatment of patients with DMD. Pamrevlumab has demonstrated a safety and tolerability profile that has supported ongoing clinical investigation in IPF, DMD, and LAPC. Pamrevlumab is an investigational drug and not approved for marketing by any regulatory authority. For information about pamrevlumab studies currently recruiting patients, please visit  

About Idiopathic Pulmonary Fibrosis (IPF)        
Idiopathic pulmonary fibrosis is a chronic lung disease characterized by a progressive and irreversible decline in lung function in which lung tissue becomes damaged, stiff, and scarred. As tissue scarring progresses, transfer of oxygen into the bloodstream is increasingly impaired, leading to irreversible loss of lung function, as well as high morbidity and mortality.

Patients with IPF experience debilitating symptoms, including shortness of breath and difficulty performing routine functions, such as walking and talking. Other symptoms include chronic dry, hacking cough, fatigue, weakness, discomfort in the chest, loss of appetite, and weight loss. Over the last decade, refinements in diagnosis criteria and enhancements in high-resolution computed tomography imaging technology (HRCT) have enabled more reliable diagnosis of IPF without the need for a lung biopsy.

In the US, there is a prevalence of approximately 120,000 patients with IPF, with approximately 30,000 patients diagnosed each year. We believe the number of patients will continue to grow due to heightened awareness and improved methods for detection and diagnosis.

About FibroGen
FibroGen, Inc. is a biopharmaceutical company committed to discovering, developing, and commercializing a pipeline of first-in-class therapeutics. The Company applies its pioneering expertise in connective tissue growth factor (CTGF) biology and hypoxia-inducible factor (HIF) to advance innovative medicines for the treatment of unmet needs. Pamrevlumab, an anti-CTGF human monoclonal antibody, is in clinical development for the treatment of idiopathic pulmonary fibrosis (IPF), locally advanced unresectable pancreatic cancer (LAPC), metastatic pancreatic cancer, and Duchenne muscular dystrophy (DMD). Roxadustat (爱瑞卓®, EVRENZOTM) is currently approved in China, Europe, Japan, and numerous other countries for the treatment of anemia in CKD patients on dialysis and not on dialysis. Roxadustat is in Phase 3 clinical development in the U.S. and Europe for anemia associated with myelodysplastic syndromes (MDS), and in Phase 3 clinical development in China for treatment of chemotherapy-induced anemia (CIA). FibroGen recently expanded its research and development portfolio to include product candidates in the immuno-oncology space. For more information, please visit

Forward-Looking Statements
This release contains forward-looking statements regarding FibroGen’s strategy, future plans and prospects, and the timing of potential events, including statements regarding the development and commercialization of the company’s product candidates, the potential safety and efficacy profile of its product candidates, and timelines for our clinical programs. These forward-looking statements include, but are not limited to, statements about FibroGen’s plans and objectives and typically are identified by use of terms such as “may,” “will”, “should,” “on track,” “could,” “expect,” “plan,” “anticipate,” “believe,” “estimate,” “predict,” “potential,” “continue” and similar words, although some forward-looking statements are expressed differently. FibroGen’s actual results may differ materially from those indicated in these forward-looking statements due to risks and uncertainties related to the continued progress and timing of its various programs, including the enrollment and results from ongoing and potential future clinical trials, and other matters that are described in FibroGen’s Annual Report on Form 10-K for the fiscal year ended December 31, 2022, as filed with the Securities and Exchange Commission (SEC) on February 27, 2023, including the risk factors set forth therein. Investors are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this release, and FibroGen undertakes no obligation to update any forward-looking statement in this press release, except as required by law.

FibroGen, Inc.

Michael Tung, M.D.
Corporate Strategy / Investor Relations

Meichiel Keenan
Director, Investor Relations & Corporate Communications