Halozyme Therapeutics, Inc. Announces 22% Increase In IVF ICSI Fertilization Rates In Eggs Treated With Cumulase Versus Bovine Extract

SAN DIEGO, May 4 /PRNewswire-FirstCall/ -- Halozyme Therapeutics, Inc. , a biopharmaceutical company developing and commercializing recombinant human enzymes, today announced the publication of clinical data showing increased fertilization rates in oocytes (eggs) that were treated with Cumulase(R) prior to in vitro fertilization (IVF) using the intracytoplasmic sperm injection (ICSI) procedure. In this prospective, randomized, blinded, sibling oocyte clinical trial, the per-patient rate of fertilization following ICSI in mature eggs treated with Cumulase was 85.3% versus 70.0% for eggs treated with Hyase(TM), a traditional bovine-derived extract product, representing a 22% increase in fertilization rate (p<0.05). In addition, the data showed a trend toward higher quality embryos with Cumulase (43% of excellent quality) compared to Hyase (25%).

The study involved 26 patients and 402 oocytes. The paper, “Comparison of bovine- and recombinant human-derived hyaluronidase with regard to fertilization rates and embryo morphology in a sibling oocyte model: a prospective, blinded, randomized study,” was published in the May issue of Fertility & Sterility, the official journal of the American Society for Reproductive Medicine and six other reproductive medical societies. The authors of the paper include Tyl H. Taylor, an embryologist, and Z. Peter Nagy, MD, PhD, Scientific and Laboratory Director, both of Reproductive Biology Associates in Atlanta, Georgia.

“These data are extremely encouraging,” said Dr. Nagy. “Cumulase has not only helped us standardize a key step in the process, but also paid dividends in increasing our ICSI fertilization rates. We now routinely achieve an over 85% ICSI fertility rate using Cumulase, compared to the national average of 70 to 75 percent.”

“We are very excited about the data,” said Jonathan Lim, MD, Halozyme’s President and CEO. “In addition to providing a safer, purer and more reliable alternative to slaughterhouse-derived enzymes, the data consistently show that the use of Cumulase also results in higher fertility rates. Patients are generally unaware of the bovine or ovine nature of materials used in ICSI and we believe that Cumulase provides patients, in addition to IVF professionals, with a superior alternative.”

A subsequent, randomized, blinded, parallel group, multicenter trial is currently underway to further characterize the benefits of Cumulase, including an evaluation of longer term clinical outcomes.

Cumulase is an ex vivo formulation of rHuPH20 (recombinant human PH20 hyaluronidase), which may replace bovine and ovine extracts currently used for the preparation of oocytes prior to IVF during the process of ICSI. The enzyme is an essential component of ICSI and removes the hyaluronic acid that surrounds the oocyte, allowing the clinician to then perform ICSI, injecting the sperm into the oocyte. Cumulase provides the IVF specialist with a safer, purer and more effective alternative to slaughterhouse-derived extracts.

The total Cumulase market consists of an estimated 500,000 ICSI cycles worldwide in 2005, with nearly 90,000 of those performed in the U.S. Halozyme received CE Mark approval of Cumulase in December 2004 to market the product throughout the European Union. In April 2005, Halozyme received 510(k) clearance from the FDA to market the product in the U.S. Cumulase is the first and only recombinant human hyaluronidase product approved for cumulus removal in the IVF process. The company has signed agreements with MediCult A/S and MidAtlantic Diagnostics, Inc. to distribute Cumulase worldwide.

About Halozyme Therapeutics, Inc.

Halozyme is a biopharmaceutical company developing and commercializing recombinant human enzymes for the drug delivery, palliative care, oncology, and infertility markets. The company’s portfolio of products is based on intellectual property covering the family of human enzymes known as hyaluronidases. Halozyme’s recombinant human enzymes may replace current animal slaughterhouse-derived extracts that carry potential risks of animal pathogen transmission and immunogenicity. The company has received FDA approval for two products: Cumulase(R), the first and only recombinant human hyaluronidase for cumulus removal in the IVF process; and Hylenex, for use as an adjuvant to increase the absorption and dispersion of other injected drugs. The versatility of the first enzyme, rHuPH20, enables Halozyme to develop the product as a medical device, drug enhancement agent, and therapeutic drug.

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Halozyme Contact Investor Relations Contacts David A. Ramsay Zachary Bryant Chief Financial Officer Lippert/Heilshorn & Associates (858) 794-8889 (310) 691-7100 dramsay@halozyme.comzbryant@lhai.com Media Contacts Kathy Sweeney / Joleen Schultz Mentus 858-455-5500, x230/x215 kwitz@mentus.comjschultz@mentus.com

Halozyme Therapeutics, Inc.

CONTACT: David A. Ramsay, Chief Financial Officer of HalozymeTherapeutics, Inc., +1-858-794-8889, dramsay@halozyme.com; or InvestorRelations, Zachary Bryant of Lippert/Heilshorn & Associates,+1-310-691-7100, zbryant@lhai.com, for Halozyme Therapeutics, Inc.; orMedia, Kathy Sweeney, ext. 230, kwitz@mentus.com, or Joleen Schultz,jschultz@mentus.com, ext. 215, both of Mentus, +1-858-455-5500, forHalozyme Therapeutics, Inc.