Halozyme Therapeutics Appoints Jonathan Leff, M.D. as Vice President, Chief Medical Officer

Halozyme Therapeutics, Inc. (Nasdaq: HALO), a biopharmaceutical company developing and commercializing products targeting the extracellular matrix, today announced the appointment of Jonathan Leff, M.D., as vice president and chief medical officer. Dr. Leff, previously the vice president and global head of inflammation clinical development at Roche, brings extensive experience in pharmaceutical product development from early stage molecules to global regulatory filing, approval and launch.

"Dr. Jonathan Leff is a highly accomplished leader with a proven track record of successfully developing and commercializing large and small molecules across a broad range of therapeutic areas. I am delighted to welcome such a talented executive to Halozyme,” said Jonathan Lim, M.D., Halozyme’s president and CEO. "This latest addition to the leadership team is indicative of Halozyme’s strong commitment and ability to attract some of the best and brightest talent in the biopharmaceutical industry.”

"I had very high regard for Halozyme and their novel technology while I was overseeing inflammation clinical development at Roche,” said Dr. Leff. "I am thrilled to be joining the Halozyme team at this exciting stage of the company’s growth to help them advance their products through the clinic.”

While at Roche, Dr. Leff managed the worldwide clinical and registration phase of development for MabThera™/Rituxan™, ocrelizumab, and Actemra™. From 2002 to 2007, Dr. Leff was at Amgen Inc., where he was vice president, North American medical affairs. His responsibilities included leadership of a department of 500 professionals, and the oversight of 5 therapeutic areas, 8 marketed products, and 4 late stage pipeline products, which involved the support and growth of 5 blockbuster brands: Neupogen™, Neulasta™, Epogen™, Aranesp™, and Enbrel™. In his prior role at Amgen as senior medical director and department head of osteoporosis research, he was responsible for the Phase 2 and 3 osteoporosis clinical trials for denosumab in over 10,000 patients, including a 7,800 patient fracture study. From 1994 to 2002, Dr. Leff was at Merck & Co., where he performed Phase 1 through Phase 4 clinical research studies for Singulair™, a treatment for asthma, which resulted in a global filing and regulatory approval.

Earlier in his career, Dr. Leff was a faculty member in the Pulmonary Division of the University of Colorado School of Medicine, with responsibilities for patient care, teaching and basic research. Dr. Leff is board certified in internal medicine, pulmonary medicine, and critical care medicine. He received his B.A. in chemistry and M.D. from the University of Pennsylvania.

About Halozyme Therapeutics, Inc.

Halozyme is a biopharmaceutical company developing and commercializing products targeting the extracellular matrix for the endocrinology, oncology, dermatology and drug delivery markets. The company's portfolio of products and product candidates is based on intellectual property covering the family of human enzymes known as hyaluronidases and additional enzymes that affect the extracellular matrix. Halozyme’s Enhanze^™ Technology is a novel drug delivery platform designed to increase the absorption and dispersion of biologics. The company has key partnerships with Roche to apply Enhanze Technology to Roche’s biological therapeutics for up to 13 targets and with Baxter BioScience to apply Enhanze Technology to Baxter’s biological therapeutic compound, GAMMAGARD LIQUID^™. The product candidates in Halozyme’s research pipeline target multiple areas of significant unmet medical need. For more information visit www.halozyme.com.

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