Five Prime Therapeutics Receives FDA Orphan Drug Designation for FPA008 in Pigmented Villonodular Synovitis (PVNS)

SOUTH SAN FRANCISCO, Calif., Jan. 13, 2016 (GLOBE NEWSWIRE) — Five Prime Therapeutics, Inc. (Nasdaq:FPRX) today announced that the U.S. Food and Drug Administration (FDA) has granted Orphan Drug Designation for FPA008 for the treatment of Pigmented Villonodular Synovitis (PVNS), a locally aggressive tumor of the synovium.

“PVNS is a painful joint disease for which there are no currently approved treatments,” said Lewis T. “Rusty” Williams, M.D., Ph.D., president and chief executive officer of Five Prime. “FPA008 is our investigational antibody that we believe blocks the activation and survival of the macrophages that make up the bulk of the PVNS tumor. This orphan drug designation by the FDA highlights the need for new treatments to help patients with this rare disease.”

Orphan Drug Designation is granted by the FDA Office of Orphan Drug Products to products that treat rare diseases. The FDA defines rare diseases as those affecting fewer than 200,000 people in the United States. Orphan Drug Designation provides the sponsor certain benefits and incentives, including a period of marketing exclusivity for the first marketing application, if regulatory approval is received for the designated indication, potential tax credits for certain activities and waiver of certain administrative fees.

About PVNS
PVNS is a rare, locally aggressive tumor of the synovium.  It is characterized by local over-expression of CSF-1, which recruits macrophages into the joints, forming the non-malignant tumor mass. It is associated with high morbidity, and there are no approved therapies for the condition. FPA008 blocks the binding of CSF-1 and inhibits the activity and survival of the macrophages that form the bulk of the tumor. Five Prime is currently in a Phase 1 clinical trial studying FPA008 as a treatment for PVNS.

About FPA008
FPA008 is an investigational antibody that inhibits CSF1R and has been shown in preclinical models to block the activation and survival of monocytes and macrophages. Inhibition of CSF1R in preclinical models of several cancers reduces the number of immunosuppressive tumor-associated macrophages (TAMs) in the tumor microenvironment, thereby facilitating an immune response against tumors. FPA008 is currently in phase 1 clinical trials in PVNS and oncology indications. FPA008 is being developed under an exclusive worldwide license and collaboration agreement with Bristol-Myers Squibb (BMS).

About Five Prime
Five Prime Therapeutics, Inc. discovers and develops innovative therapeutics to improve the lives of patients with serious diseases. Five Prime’s comprehensive discovery platform, which encompasses virtually every medically relevant extracellular protein, positions it to explore pathways in cancer, inflammation and their intersection in immuno-oncology, an area with significant therapeutic potential and a growing focus of the company’s R&D activities. Five Prime has entered into strategic collaborations with leading global pharmaceutical companies and has promising product candidates in clinical and preclinical development. For more information, please visit

Cautionary Note on Forward-looking Statements
This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Words such as “may,” “will,” “expect,” “plan,” “anticipate,” “estimate,” “intend” and similar expressions (as well as other words or expressions referencing future events, conditions or circumstances) are intended to identify forward-looking statements. These forward-looking statements are based on Five Prime’s expectations and assumptions as of the date of this press release. Each of these forward-looking statements involves risks and uncertainties. Actual results may differ materially from these forward-looking statements. Factors that may cause actual results to differ from those expressed or implied in the forward-looking statements in this press release are discussed in Five Prime’s filings with the U.S. Securities and Exchange Commission, including the “Risk Factors” contained therein. Except as required by law, Five Prime assumes no obligation to update any forward-looking statements contained herein to reflect any change in expectations, even as new information becomes available. 


Heather Rowe
Investor Relations

Amy Kendall,
Corporate Communications