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HALOZYME CONTACT                                  INVESTOR RELATIONS CONTACTS
David A. Ramsay                                   Ina McGuinness or Bruce Voss
Chief Financial Officer                           Lippert/Heilshorn & Associates
(858) 794-8889                                    (310) 691-7100
dramsay@halozyme.com                              imcguinness@lhai.com

                                                  MEDIA CONTACTS
                                                  Kathy Sweeney/ Megan Riggs
                                                  Mentus
                                                  858-455-5500, x212/x215
                                                  kwitz@mentus.com
                                                  megan@mentus.com

                   HALOZYME THERAPEUTICS NAMES KENNETH KELLEY
                              TO BOARD OF DIRECTORS

         EDWARD MERCALDO STEPS DOWN TO FOCUS ON OTHER BUSINESS INTERESTS

SAN DIEGO, CALIF., MAY 24, 2004 - Halozyme Therapeutics, Inc. (OTCBB: HZYM), a
therapeutically driven biopharmaceutical company focused on the development and
commercialization of recombinant human enzymes, today announced that Kenneth
Kelley has been named to its Board of Directors. In addition, Edward Mercaldo is
stepping down from the board to pursue other business activities.

"We are extremely pleased that Ken has agreed to join our board," said Dr. Lim.
"Ken brings extensive strategic and operational biotechnology experience to
Halozyme and can assist the company in its progress towards commercialization of
its first products. At the same time, we are sorry to see Ed step down, as he
has made an invaluable contribution to Halozyme's early development. We wish Ed
the best as he focuses on his other business interests."

Mr. Kelley brings over 20 years of entrepreneurial, venture capital,
operational, and technical biotechnology experience to Halozyme. He is an active
investor and mentor to biotechnology entrepreneurs and serves on three private
company boards. Previously, he was a General Partner at Latterell Venture
Partners, where he made investments in early stage biotechnology and medical
device startups. Ken founded and led IntraBiotics Pharmaceuticals (NASDAQ:
IBPI), serving as Founder, CEO, Director and Chairman. Over 8 years from
startup, Ken led a team that discovered and developed a new class of antibiotics
from lead through phase III clinical trials, raised over $100 million of venture
capital and international corporate partnerships, and took the company public in
2000. Earlier, Ken was an Associate at Institutional Venture Partners (IVP),
where he participated in the financing of 20 biotech and medical companies
resulting in 15 IPO's. Prior to IVP, Ken was a consultant for McKinsey & Company
and a scientist at Integrated Genetics (acquired by Genzyme). He has an MBA from
Stanford and a BA in biochemical sciences from Harvard.




Halozyme's recombinant human enzyme technology replaces current animal
slaughterhouse-derived enzymes that carry risks of animal pathogen contamination
and immunogenicity. The Company believes that the versatility of its first
enzyme, rHuPH20, will enable Halozyme to simultaneously market the product as a
medical device, a drug enhancement agent, and a therapeutic biologic.

ABOUT HALOZYME THERAPEUTICS, INC.
Halozyme is a therapeutically driven biopharmaceutical company dedicated to the
development and commercialization of recombinant human enzymes for the
infertility, ophthalmology, and oncology communities. The company's broad
product portfolio is based on intellectual property covering the family of human
enzymes known as hyaluronidases. The company's lead products offer a safe and
pure alternative to existing slaughterhouse-derived extracts that carry risks of
animal pathogen contamination and immunogenicity. The commercialization of
Halozyme's highly versatile enzyme technology within proven markets will enable
the company to significantly impact the quality of medicine.

SAFE HARBOR STATEMENT
In addition to historical information, the statements set forth above include
forward-looking statements (including, without limitation, statements concerning
the marketing and distribution methods Halozyme intends to employ with respect
to its first enzyme) 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 also identified through use of the words
"believes," "execute," "enable" and other words of similar meaning. Factors that
may result in differences are discussed in greater detail in Halozyme
Therapeutics' Annual Report on Form 10-K and other filings with the Securities
and Exchange Commission.

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