Additional preclinical data highlights the pharmacologic properties of PEGPH20

SAN DIEGO, April 8, 2014 /PRNewswire/ -- Halozyme Therapeutics, Inc. (NASDAQ: HALO) today announced that two scientific poster presentations on the pharmacology of PEGPH20 will be made at the American Association for Cancer Research (AACR) annual meeting being held in San Diego. The first presentation includes preclinical data showing that treatment of tumors with PEGPH20 enhances the action of immune-based cancer therapy such as monoclonal antibodies (mAbs). The second presentation includes preclinical data showing that overproduction of hyaluronan (HA) in tumor stroma enhances tumor growth, and that PEGPH20, as a single agent, suppresses growth of HA-rich tumors and inhibits early events of epithelial to mesenchymal transition (EMT), a key process involved in metastasis. PEGPH20 is an investigational PEGylated form of rHuPH20 under development by Halozyme, which degrades the hyaluronan coating that may provide a supportive environment in many solid tumors.

"These findings advance our understanding of the pharmacology of PEGPH20 and offer new scientific insight into ways to utilize PEGPH20 to potentially improve cancer therapies," stated H. Michael Shepard, Ph.D., Vice President and Chief Scientific Officer. "These data show in preclinical models the potential antimetastatic effects of PEGPH20, as well as PEGPH20's ability to work in combination with chemotherapy and targeted agents, like monoclonal antibodies."

ACR Poster Presentation Details

Title: "Pegylated Recombinant Human Hyaluronidase PH20 (PEGPH20) Enhances Cetuximab Efficacy in BxPC-3/HAS3 Human Pancreatic Cancer Xenografts"
Abstract #: 3646, April 8, 2014, 8:00AM - 12:00PM PDT
Location: Hall A-E, Poster Section 26
Summary: HA accumulation creates a coating that surrounds certain solid tumor cells and protects them from attack by therapeutic antibodies. HA-overexpressed PDA tumors treated with PEGPH20 enhance the immune activating antibodies and anti-tumor activity of mAbs, such as Cetuximab.

Title: "Extracellular Hyaluronan Accumulation by Hyaluronan Synthase 3 Promotes
Pancreatic Cancer Growth and Modulates Tumor Microenvironment via Epithelial-Mesenchymal Transition"
Abstract #:  4844,April 9, 2014, 8:00AM - 12:00PM PDT
Location: Hall A-E, Poster Section 2
Summary: These data demonstrate that HA accumulation by hyaluronan synthase 3 (HAS3) enzyme favors pancreatic cancer growth in animal models. In addition, PEGPH20, as a single agent, inhibits tumor growth and reduces early events associated with EMT.

About Halozyme

Halozyme Therapeutics is a biopharmaceutical company dedicated to developing and commercializing innovative products that advance patient care. With a diversified portfolio of enzymes that target the extracellular matrix, the Company's research focuses primarily on a family of human enzymes, known as hyaluronidases, which increase the dispersion and absorption of biologics, drugs and fluids. Halozyme's pipeline addresses therapeutic areas, including oncology, diabetes and dermatology that have significant unmet medical need today. The Company markets Hylenex® recombinant (hyaluronidase human injection) and has partnerships with Roche, Pfizer and Baxter. Halozyme is headquartered in San Diego, CA. For more information on how we are innovating, please visit our corporate website at www.halozyme.com.

Safe Harbor Statement

In addition to historical information, the statements set forth above include forward-looking statements (including, without limitation, statements concerning the possible activity, benefits and attributes of PEGPH20, the possible method of action of PEGPH20, its potential application to improve cancer therapies and statements concerning future actions relating to the development of PEGPH20) that involve risk and uncertainties that could cause actual results to differ materially from those in the forward-looking statements. The forward-looking statements are typically, but not always, identified through use of the words "believe," "enable," "may," "will," "could," "intends," "estimate," "anticipate," "plan," "predict," "probable," "potential," "possible," "should," "continue," and other words of similar meaning. Actual results could differ materially from the expectations contained in forward-looking statements as a result of several factors, including unexpected expenditures and costs, unexpected results or delays in development and regulatory review, regulatory approval requirements, unexpected adverse events and competitive conditions. These and other factors that may result in differences are discussed in greater detail in the Company's Annual Report on Form 10-K filed with the Securities and Exchange Commission on February 28, 2014.

Investor Contact:
Schond Greenway
Halozyme Therapeutics
858-704-8352
ir@halozyme.com

Media Contact:
Denise Powell
510-703-9491
dpowell@brewlife.com

SOURCE Halozyme Therapeutics, Inc.

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