FibroGen Advances Phase 3 Clinical Development of Pamrevlumab for the Treatment of Idiopathic Pulmonary Fibrosis with Initiation of ZEPHYRUS-2

SAN FRANCISCO, Dec. 22, 2020 (GLOBE NEWSWIRE) — FibroGen, Inc. (NASDAQ: FGEN) today announced dosing of the first patient in the ZEPHYRUS-2 Phase 3 clinical study of pamrevlumab in patients with idiopathic pulmonary fibrosis (IPF), a chronic, progressive, and fatal lung disease.

“Today, treatment for IPF is aimed at relieving symptoms and slowing disease progression, and disease-modifying treatment options are urgently needed,” said Elias Kouchakji, M.D., Senior Vice President, Clinical Development and Drug Safety. “We are excited to advance the Phase 3 clinical development program for pamrevlumab, a first-in-class antibody which represents a novel approach to the treatment of IPF, a disease with survival rates comparable to those of some of the deadliest cancers.”

ZEPHYRUS-2 is a 52-week randomized, double-blind, placebo-controlled, multi-center Phase 3 trial designed to evaluate the efficacy and safety of pamrevlumab in subjects with IPF who were previously treated with an approved therapy but who discontinued that therapy. 

The primary endpoint of the study is disease progression defined as a change from baseline in forced vital capacity (FVC) percent predicted decline ≥10% or death. Secondary endpoints include change in quantitative lung fibrosis (QLF) and patient-reported outcomes. Approximately 340 subjects will be enrolled into the global study. Subjects who complete the 52-week study may be eligible for rollover into a separate study offering open-label, extension treatment with pamrevlumab. For more information about ZEPHYRUS-2 please visit www.clinicaltrials.gov (NCT04419558).

“The initiation of our second Phase 3 study of pamrevlumab for IPF furthers our research on the clinical benefits of inhibiting connective tissue growth factor (CTGF), an important biological mediator in fibrotic and proliferative disorders,” said Mark Eisner, M.D, M.P.H, Chief Medical Officer, FibroGen. “We are committed to advancing the science of CTGF biology and evaluating clinical benefit in diverse diseases with unmet medical need, including IPF, locally advanced unresectable pancreatic cancer and Duchenne muscular dystrophy.”

The Phase 3 clinical development program for pamrevlumab for IPF consists of two studies, ZEPHYRUS and ZEPHYRUS-2. ZEPHYRUS is an ongoing randomized, double-blind, placebo-controlled, multi-center Phase 3 trial designed to evaluate the efficacy and safety of pamrevlumab in subjects with IPF over a 52-week period. The primary endpoint of the study is the change in forced vital capacity (FVC) from baseline. For more information about ZEPHYRUS please visit www.clinicaltrials.gov (NCT03955146).

The design of ZEPHYRUS and ZEPHYRUS-2 is supported by safety and efficacy data from two Phase 2 studies. In a Phase 2, randomized, double-blind, placebo-controlled trial of pamrevlumab in IPF (Study 067/PRAISE), pamrevlumab demonstrated a statistically significant difference over placebo in the primary efficacy endpoint of FVC percent predicted change from baseline to Week 48 (Gorina, ERS 2017). Pamrevlumab achieved superiority over placebo in the following secondary endpoints: the proportion of subjects with disease progression (defined as a change from baseline in FVC percent predicted decline ≥10% or death), time to disease progression, change from baseline to Week 48 in quantitative lung fibrosis (QLF) score to Week 48 measured by quantitative HRCT. In addition, there was a trend towards improvement in patient-reported quality of life measurements assessed by the SGRQ (positive trends) and the UCSD-SOBQ, as well as favorable trend in all-cause mortality. 

In a prior single-arm, open-label FGCL-3019-049 study, the treatment of patients with IPF given 15 mg/kg and 30 mg/kg IV of pamrevlumab every three weeks was associated with improvement or stability in quantified scores of whole lung fibrosis in approximately 35% of subjects at Week 48 (Raghu, 2012). Changes from baseline in these scores were significantly correlated with changes in FVC percent predicted value (Raghu, 2012).  

About Pamrevlumab
Pamrevlumab is a first-in-class antibody 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) and for the treatment of locally advanced unresectable pancreatic cancer (LAPC), and in Phase 2 clinical development for the treatment of Duchenne muscular dystrophy (DMD). The U.S. Food and Drug Administration has granted Orphan Drug Designation (ODD) to pamrevlumab for the treatment of patients with IPF, LAPC, and DMD. Pamrevlumab has also received Fast Track designation from the U.S. Food and Drug Administration for the treatment of patients with IPF and LAPC. Across all clinical studies, pamrevlumab has consistently demonstrated a good safety and tolerability profile to date. For information about pamrevlumab studies currently recruiting patients, please visit www.clinicaltrials.gov.

About Idiopathic Pulmonary Fibrosis (IPF)
Idiopathic pulmonary fibrosis is a chronic lung disease characterized by a progressive and irreversible decline in lung function when 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 rates. Average life expectancy is estimated to be three to five years from diagnosis with approximately two-thirds of patients dying within five years. Survival rates are comparable to those of some of the deadliest cancers.

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.

U.S. prevalence and incidence of IPF is estimated to be 135,000 cases (defined by ICD-9 code) and 21,000 new cases per year, respectively, based on Raghu et al. (Am J Respir Crit Care Med, 2006) and on data from the United Nations Population Division. 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 hypoxia-inducible factor (HIF) and connective tissue growth factor (CTGF) biology to advance innovative medicines for the treatment of unmet needs. The Company is currently developing and commercializing roxadustat, an oral small molecule inhibitor of HIF prolyl hydroxylase activity, for anemia associated with chronic kidney disease (CKD). Roxadustat is also in clinical development for anemia associated with myelodysplastic syndromes (MDS) and for chemotherapy-induced anemia (CIA). 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), Duchenne muscular dystrophy (DMD), and coronavirus (COVID-19). For more information, please visit www.fibrogen.com.

Forward-Looking Statements
This release contains forward-looking statements regarding our strategy, future plans and prospects, including statements regarding the development and commercialization of the company’s product candidates, the potential safety and efficacy profile of our product candidates, our clinical programs and regulatory events, and those of our partners. These forward-looking statements include, but are not limited to, statements about our plans, objectives, representations and contentions and are not historical facts 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. Our 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 our various programs, including the enrollment and results from ongoing and potential future clinical trials, and other matters that are described in our Annual Report on Form 10-K for the fiscal year ended December 31, 2019 and our Quarterly Report on Form 10-Q for quarter ended September 30, 2020 filed with the Securities and Exchange Commission (SEC), 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 we undertake no obligation to update any forward-looking statement in this press release, except as required by law.

Contacts:
FibroGen, Inc.

Investors:
Michael Tung, M.D.
Corporate Strategy / Investor Relations
1.415.978.1434
mtung@fibrogen.com

Media:
Jennifer Harrington
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Jennifer.Harrington@gcihealth.com