(HALO) To Resume PEGPH20 Clinical Program In Pancreatic Cancer

FDA Removes Clinical Hold on Phase 2 Trial (Study 202)

SAN DIEGO, June 4, 2014  — Halozyme Therapeutics, Inc. (NASDAQ: HALO) today announced that the U.S. Food and Drug Administration (FDA) has removed the clinical hold on patient enrollment and dosing of PEGPH20 in the ongoing Phase 2 trial (Study 202) evaluating PEGPH20 in patients with pancreatic cancer permitting the study to resume under a revised protocol. Patient enrollment is anticipated to recommence upon review and approval of the amended protocol by the Independent Review Boards at the participating clinical trial sites. In May, the trial’s independent Data Monitoring Committee (DMC) recommended that enrollment and dosing in the study resume under a revised protocol.

“We are committed to the development of PEGPH20 in pancreatic cancer. Halozyme worked diligently with the FDA and the DMC to develop the plan to allow the study to restart,” commented Dr. Helen Torley, President and CEO. “We are pleased to be able to continue enrolling patients in this clinical program as there remains a significant need for new treatment options for pancreatic cancer patients.”

About Study 202
Study 202 (Halo 109-202) is a Phase 2 multicenter, randomized clinical trial evaluating PEGPH20 as a first-line therapy for treatment of patients with stage IV metastatic pancreatic cancer. The primary outcome of the trial is to measure improvement in progression-free survival in patients receiving PEGPH20 in combination with gemcitabine and nab-paclitaxel compared to gemcitabine and nab-paclitaxel alone. A second primary endpoint has been added to assess the thromboembolic event rate in the PEGPH20 treatment arm following the protocol amendment. Secondary endpoints include objective response rate and overall survival. The protocol amendments to the study include the exclusion of patients who may be at higher risk of thromboembolic events. Additionally, low-molecular weight heparin will be used as a prophylaxis to prevent thromboembolic events. In addition to the over 100 patients already enrolled in the trial, Halozyme plans to enroll a similar number of additional patients.

About PEGPH20
PEGPH20 is an investigational PEGylated form of Halozyme’s proprietary recombinant human hyaluronidase under development for the systemic treatment of tumors that accumulate hyaluronan.

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 future actions relating to the development of PEGPH20 such as the anticipated resumption of enrollment and dosing of PEGPH20 in Study 202, enrollment of additional patients in the study, and the possibility that PEGPH20 may be used to address pancreatic cancer) 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 the possibility that the revised protocol may not address the apparent increased rate of thromboembolic events observed with the use of PEGPH20 in the trial or satisfy future regulatory requirements, the possibility of additional safety events, 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 Halozyme’s Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission on May 12, 2014.

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

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