• FOR46, an ADC targeting CD46, is in Phase 1 development with potential applications in mCRPC and other CD46-expressing cancers
• Collaboration expands FibroGen's clinical pipeline with potential first-in-class product candidate

SAN FRANCISCO and LA JOLLA, Calif., May 08, 2023 (GLOBE NEWSWIRE) -- FibroGen, Inc. (Nasdaq: FGEN) and Fortis Therapeutics announced that FibroGen has entered into an exclusive license with Fortis Therapeutics for FOR46, a potential first-in-class Phase 1 antibody-drug conjugate (ADC) targeting a novel epitope on CD46. FOR46 is being developed for the treatment of metastatic castration-resistant prostate cancer (mCRPC) and is being explored for use in other CD46 expressing cancers. As part of the clinical development strategy, FibroGen will continue Fortis Therapeutics' work to develop a PET-based biomarker utilizing a radiolabeled version of the targeting antibody (PET46) for patient selection.

"The agreement with Fortis Therapeutics bolsters FibroGen's clinical pipeline in a capital-efficient manner, providing a product candidate with the potential to address a significant unmet medical need in oncology," said Enrique Conterno, Chief Executive Officer, FibroGen. "FOR46 is a natural fit with our R&D capabilities and expertise. The flexibility of the agreement gives us the opportunity to clinically develop FOR46, and ultimately acquire it as a Phase 3-ready asset, potentially delivering a therapy that may transform the treatment of patients with mCRPC and other CD46 expressing cancers."

"We are pleased to partner with the team at FibroGen, who are experienced in advancing novel drug candidates in the clinic for life-threatening diseases," said Jay Lichter, Ph.D., President and CEO of Fortis and Managing Partner of Avalon Bioventures. "We believe that FOR46 is a novel and unique antibody drug conjugate therapy that could help patients with prostate cancer and other cancers, where currently approved treatments have failed."

Under the terms of the agreement, there is no upfront consideration. FibroGen will conduct and fund future research, development, and manufacturing of FOR46 and PET46. During the four-year evaluation period, FibroGen has the option to acquire Fortis Therapeutics for $80 million. In addition, Fortis is eligible to receive up to a total of $200 million based on various regulatory approvals.

About FOR46

FOR46 is an antibody drug conjugate that binds a specific conformational epitope of CD46 that is highly expressed in various cancer types, including multiple myeloma and prostate and colorectal tumors, with limited reactivity against normal tissues. FOR46 is a fully human antibody conjugated to MMAE, a potent cytotoxic payload utilized in a variety of approved ADCs. Early clinical data show FOR46 to be generally well tolerated with demonstrated monotherapy activity in multiple myeloma and mCRPC.

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, EVRENZO) 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 clinical development for anemia of chronic kidney disease (CKD) and anemia associated with myelodysplastic syndromes (MDS), and for 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 .

About Fortis Therapeutics

Fortis Therapeutics is an immuno-oncology biotech developing a novel antibody-drug conjugate for late-stage multiple myeloma and metastatic castration-resistant prostate cancer. Fortis was founded based on technology exclusively licensed from UCSF and developed in the laboratory of Bin Liu, Ph.D. Fortis is located in Avalon Bioventures's Community of Innovation, in San Diego. FOR46 is Fortis' sole pharmaceutical asset. 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.

Contacts:
FibroGen, Inc.

Investors:
Michael Tung, M.D.
Corporate Strategy / Investor Relations
415.978.1434
mtung@fibrogen.com

Media:
Meichiel Jennifer Keenan
Investor Relations/Corporate Communications
mkeenan@fibrogen.com

Fortis Therapeutics
Media:
Jessica Yingling
858.344.8091
jessica@litldog.com