Seattle Genetics Announces Management Team Addition and Promotion to Support SGN-35 Commercialization Initiatives

Company Also Recognizes Dr. Peter Senter as Distinguished Fellow
BOTHELL, Wash.--(Business Wire)--
Seattle Genetics, Inc. (Nasdaq:SGEN) today announced the appointment of Vaughn
B. Himes, Ph.D., as Executive Vice President, Technical Operations and the
promotion of Morris Z. Rosenberg, D.Sc., to Executive Vice President, Process
Sciences. In addition, the company has recognized Peter D. Senter, Ph.D., Vice
President, Chemistry, as the company`s first Distinguished Fellow.

"We are continuing to strengthen our management team and position the company to
deliver on our substantial product development goals, including the planned
commercial launch of SGN-35 in 2012," said Clay B. Siegall, Ph.D., President and
Chief Executive Officer of Seattle Genetics. "Vaughn brings a strong background
in commercial manufacturing and supply chain management, and has been involved
in several successful drug approval submissions. Morris continues to demonstrate
substantial operational expertise and leadership as Seattle Genetics has
advanced its broad product pipeline into late-stage clinical trials. Together,
these seasoned executives will play a key role in guiding our development and
manufacturing initiatives across our pipeline, including our SGN-35 new drug
application."

Regarding Dr. Senter`s recognition as Distinguished Fellow, Dr. Siegall added,
"Peter is a world-renowned research scientist and leader in the field of
antibody-drug conjugates (ADCs). His body of work, including his key role with
SGN-35 and the company`s ADC technology, provides evidence of his significant
impact on Seattle Genetics and the global scientific community."

Vaughn Himes brings to Seattle Genetics more than twenty years of experience in
manufacturing, technical operations, process development and scale-up
activities. As Executive Vice President, Technical Operations, he will oversee
Seattle Genetics` manufacturing, supply chain and quality assurance and control
functions. Previously, Dr. Himes was with Zymogenetics, Inc., most recently as
Senior Vice President, Technical Operations where his responsibilities included
commercial and clinical manufacturing, supply chain and logistics, quality
control and process development. While at Zymogenetics, he oversaw the
chemistry, manufacturing and control (CMC) portion of the successful Biologics
License Application for Recothrom and managed its commercial supply. Previously,
he held Vice President positions in manufacturing and development at Corixa,
Targeted Genetics and Genovo. Dr. Himes received a Bachelor of Arts in Chemistry
from Pomona College in California and a Ph.D. in Chemical Engineering from the
University of Minnesota.

Morris Rosenberg joined Seattle Genetics in July 2001 and has overseen
significant growth of the company`s development organization, including the
process development, quality assurance and control, analytical biochemistry,
formulation and manufacturing functions. Previously, Dr. Rosenberg was with Eli
Lilly, Biogen (now Biogen Idec) and Invitron. While at Biogen, he participated
in the development of the manufacturing process for the multiple sclerosis
treatment Avonex. Dr. Rosenberg received a D.Sc. in Chemical Engineering, an
M.S. and B.S. in Chemical Engineering, and a B.A. in Biology from Washington
University in St. Louis, Missouri.

Peter Senter joined Seattle Genetics in August 1998 and has served as Vice
President, Chemistry since September 2002. He leads the company's chemistry
department, which is focused on ADC technologies, including the development of
potent drug payloads, novel linker systems, conjugation methodology and
mechanism of action studies. Prior to joining Seattle Genetics, Dr. Senter was
with Cytokine Networks, the Bristol-Myers Squibb Pharmaceutical Research
Institute and the Dana-Farber Cancer Institute, Harvard Medical School. Dr.
Senter has authored more than 100 scientific publications and holds more than 20
patents. He received a Ph.D. in Chemistry from the University of Illinois, and
an A.B. in Biochemistry from the University of California, Berkeley.

About Seattle Genetics

Seattle Genetics is a clinical stage biotechnology company focused on the
development and commercialization of monoclonal antibody-based therapies for the
treatment of cancer and autoimmune disease. The company`s lead product
candidate, SGN-35, is in a pivotal trial under a special protocol assessment
with the FDA. SGN-35 is empowered by Seattle Genetics` proprietary ADC
technology comprising highly potent synthetic drugs and stable linkers for
attaching the drugs to monoclonal antibodies. In addition, Seattle Genetics has
three other product candidates in ongoing clinical trials: dacetuzumab (SGN-40),
lintuzumab (SGN-33) and SGN-70. Dacetuzumab is being developed under a worldwide
collaboration with Genentech. Seattle Genetics has collaborations for its ADC
technology with a number of leading biotechnology and pharmaceutical companies,
including Genentech, Bayer, CuraGen, Progenics, Daiichi Sankyo, MedImmune, a
subsidiary of AstraZeneca, and Millennium: The Takeda Oncology Company, as well
as an ADC co-development agreement with Agensys, a subsidiary of Astellas
Pharma. More information can be found at www.seattlegenetics.com.

Certain of the statements made in this press release are forward looking, such
as those, among others, relating to the company`s plan to commercially launch
SGN-35. Actual results or developments may differ materially from those
projected or implied in these forward-looking statements. Factors that may cause
such a difference include risks related to delay of commercialization of SGN-35
due to regulatory, clinical or other factors. More information about the risks
and uncertainties faced by Seattle Genetics is contained in the Company's Form
10-K for the year ended December 31, 2008 filed with the Securities and Exchange
Commission. Seattle Genetics disclaims any intention or obligation to update or
revise any forward-looking statements, whether as a result of new information,
future events or otherwise.

Seattle Genetics, Inc.
Peggy Pinkston, 425-527-4160
ppinkston@seagen.com

Copyright Business Wire 2009