Five Prime Therapeutics Enters Into Antibody Research Collaboration Agreement With Adimab

Five Prime Therapeutics Enters Into Antibody Research Collaboration Agreement
With Adimab

SOUTH SAN FRANCISCO, Calif., Jan. 9, 2014 (GLOBE NEWSWIRE) -- Five Prime
Therapeutics, Inc. (Nasdaq:FPRX), a clinical-stage biotechnology company
focused on discovering and developing novel protein therapeutics for cancer
and inflammatory diseases, today announced a sponsored research collaboration
agreement with Adimab, LLC, a leader in discovery of monoclonal and bispecific
antibodies. Five Prime will provide multiple targets to Adimab for the
discovery and optimization of therapeutic monoclonal antibodies initially
focused in cancer immunotherapy.

Under the terms of the collaboration agreement, Adimab will use its
proprietary discovery and optimization platform to identify fully-human
antibodies for Five Prime. This agreement will grant Five Prime the right to
develop and commercialize antibodies generated during the collaboration for
potential use as therapeutic products. While financial terms were not
disclosed, Adimab will be eligible to receive potential research funding,
option payments, milestone payments and royalties.

"Five Prime is in an ideal position to leverage our robust protein discovery
platform and our oncology experience to advance new targets and molecules for
cancer immunotherapy," said Lewis T. "Rusty" Williams, M.D., Ph.D., President
and Chief Executive Officer of Five Prime. "Adimab's ability to rapidly and
effectively generate therapeutic monoclonal antibody candidates should allow
us to move quickly from targets to products, as we expand our research and
development efforts in this promising therapeutic area."

"We are pleased to be entering into this partnership with Five Prime," said
Tillman Gerngross, Co-Founder and Chief Executive Officer of Adimab. "Five
Prime's productive high-throughput protein screening capabilities, in
combination with our antibody discovery platform, have the potential to lead
to the development of exciting new therapeutic agents and we look forward to
collaborating in this effort."

About Five Prime Therapeutics

Five Prime Therapeutics, Inc. is a clinical-stage biotechnology company
focused on discovering and developing novel protein therapeutics for cancer
and inflammatory diseases. Five Prime has leveraged its comprehensive library
of more than 5,700 human extracellular proteins and its proprietary
high-throughput screening technologies to produce new targets for protein
therapeutics to be advanced by partners or in the company's internal pipeline.
Five Prime's most advanced candidate is FP-1039 (GSK3052230), a fibroblast
growth factor (FGF) ligand trap that is being developed in collaboration with
GlaxoSmithKline to treat multiple solid tumors.A multi-arm Phase 1b study in
FGFR1-amplified squamous non-small cell lung cancer (NSCLC) and other tumors
is underway. Five Prime's pipeline also includes two humanized monoclonal
antibodies that modulate the immune system, FPA008 and FPA144. FPA008 inhibits
colony stimulating factor-1 receptor (CSF1R) activation and is being developed
to treat rheumatoid arthritis, with a Phase 1 trial currently enrolling.
FPA144 blocks signaling through fibroblast growth factor receptor 2b (FGFR2b)
and is expected to begin a Phase 1 study in gastric cancer by the end of 2014.

For more information please see:www.fiveprime.com

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 Five Prime's 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" section of Five Prime's quarterly report on Form
10-Q filed on November 13, 2013 with the U.S. Securities and Exchange
Commission. 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.

CONTACT: For press inquiries:
         Five Prime Therapeutics
         Amy Kendall
         Corporate Communications
         Telephone: +1-415-365-5776
         Email: amy.kendall@fiveprime.com

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