FibroGen Announces Topline Results from Phase 3 ZEPHYRUS-1 Study of Pamrevlumab for the Treatment of Idiopathic Pulmonary Fibrosis

-  Study did not meet the primary endpoint
-  Pamrevlumab was generally safe and well tolerated
-  ZEPHYRUS-2 Phase 3 study will be discontinued
-  Company to implement plan to extend cash runway into 2026

SAN FRANCISCO, June 26, 2023 (GLOBE NEWSWIRE) -- FibroGen, Inc. (NASDAQ: FGEN) today announced topline results from its Phase 3 ZEPHYRUS-1 trial evaluating the safety and efficacy of pamrevlumab in patients with idiopathic pulmonary fibrosis (IPF). The study compared treatment with pamrevlumab to placebo and did not meet the primary endpoint of change from baseline in forced vital capacity (FVC) at week 48 (p=0.29). The mean decline in FVC from baseline to week 48 was 260 ml in the pamrevlumab arm compared to 330 ml in the placebo arm (placebo-corrected difference of 70 ml; 95% CI -60 to 190 ml). The secondary endpoint of time to disease progression (FVC percent predicted decline of ≥10% or death) was also not met (HR= 0.78; 95% CI 0.52 to 1.15).

In the safety analysis, pamrevlumab was generally safe and well tolerated and the majority of treatment emergent adverse events were mild or moderate. Treatment-emergent serious adverse events were observed in 28.2% of patients in the pamrevlumab group and 34.3% of patients in the placebo group.

Based on the results of ZEPHYRUS-1, ZEPHYRUS-2, the second Phase 3 clinical trial, will be discontinued. FibroGen plans to communicate the results of the ZEPHYRUS-1 study at an upcoming medical forum.

“We are deeply disappointed that these results do not support pamrevlumab as a new treatment for IPF,” said Mark D. Eisner, MD, MPH, Chief Medical Officer, FibroGen. “FibroGen would like to thank the patients and clinical trial investigators for their dedication to participating in this study.”

FibroGen anticipates reporting topline data from Phase 3 studies with pamrevlumab for the treatment of ambulatory DMD patients (LELANTOS-2) in 3Q 2023, locally advanced pancreatic cancer (LAPIS) in 1H 2024, and metastatic pancreatic cancer (Precision Promise).

“FibroGen’s focus will be on reporting the additional pamrevlumab studies, advancing our pipeline, and continuing commercialization of roxadustat in China and in countries where approved,” said Enrique Conterno, Chief Executive Officer, FibroGen.

Upcoming Milestones:

• Topline data from the LELANTOS-2 Phase 3 study of pamrevlumab in ambulatory DMD patients expected 3Q 2023.
• Topline data from the LAPIS Phase 3 study of pamrevlumab in locally advanced unresectable pancreatic cancer (LAPC) expected 1H 2024.
• Topline data from the Pancreatic Cancer Action Network (PanCAN) Precision Promise^SM Phase 3 study of pamrevlumab in metastatic pancreatic cancer.
• Anticipate the filing of up to two INDs: FG-3165 (anti-Gal9 antibody) 1Q 2024 and FG-3163 (anti-CCR8 antibody) 4Q 2023.
• Anticipate the initiation of a Phase 2 trial of FG-3246, a first-in-class antibody-drug conjugate (ADC) targeting a novel epitope on CD46 for metastatic castration-resistant prostate cancer (mCRPC) in 2H 2024.