Exhibit 99.1

                            Filed by VaxGen, Inc.  pursuant to Rule 425 under
                            the Securities Act of 1933 and deemed filed pursuant
                            to Rule 14a-12 under the Securities Exchange Act of
                            1934


Contacts:

Investors:                                                  Media:
Lance Ignon                                                 Ellen Rose
Sitrick And Company                                         Availe Communication
415-793-8851                                                650-387-8746


                VaxGen and Raven biotechnologies Announce Signing
                         of Definitive Merger Agreement

        - Conference Call Scheduled for Tuesday, November 13, 8:00 EST -


South San  Francisco,  Calif.  -- November 12, 2007 -- VaxGen Inc. (Pink Sheets:
VXGN.PK),  a  biopharmaceutical  company,  and Raven  biotechnologies,  inc.,  a
privately  held  company  focused  on the  development  of  monoclonal  antibody
therapeutics  (MAbs) for treating cancer,  announced today that their respective
boards of directors have unanimously approved a definitive merger agreement. The
merger is expected to create a drug  development  company with a robust pipeline
of monoclonal  antibody candidates in oncology,  proprietary  antibody discovery
platforms,  biopharmaceutical  manufacturing capabilities and sufficient cash to
fund operations at least through the end of 2009.

Details of the Proposed Transaction

Under the terms of the agreement,  VaxGen shall issue,  and the holders of Raven
Series D preferred stock shall receive, in a tax-free transaction, approximately
32  million  shares  of  VaxGen  common  stock.  Following  the  closing  of the
transaction,  VaxGen  stockholders  will own  approximately  51  percent  of the
combined  company,   on  a  pro  forma  basis,  and  Raven  Series  D  preferred
stockholders  will own  approximately  49  percent.  This  ratio is  subject  to
adjustment  under  certain  circumstances  described  more  fully in the  merger
agreement,  but in no event will VaxGen  stockholders own less than 50.1 percent
of the

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combined  company on a pro forma basis. In addition,  VaxGen will assume Raven's
debt and  equipment  lease  obligations  of  approximately  $1.8  million  as of
December 1, 2007. Raven Series D preferred stock warrants will be converted into
approximately 332,000 VaxGen common stock warrants.  All other Raven options and
warrants will be cancelled.

Completion  of  the  transaction  is  conditioned   upon  the  approval  of  the
stockholders of both companies,  as well as other customary closing  conditions.
Major Raven stockholders already have executed voting agreements in favor of the
transaction.  Further  conditions  to close  include a  requirement  that VaxGen
relist its common stock on a national stock exchange, preparations for which are
underway.   VaxGen   expects   to   file   a  Form   S-4   and   related   proxy
statement/prospectus  with the U.S.  Securities  and Exchange  Commission in the
coming weeks. The merger is expected to close in the first half of 2008.

Between  signing and  closing,  Raven will receive a bridge loan of $3.8 million
from  the  holders  of Raven  Series D  preferred  stock to fund  operating  and
transaction-related  expenses.  VaxGen  will  provide a bridge  loan of up to $6
million  to fund  ongoing  operations  and to  support  advancement  of  Raven's
pipeline prior to the transaction's  closing. All principal and accrued interest
due under the VaxGen loan is repayable in full in the event the transaction does
not  close.  All  principal  and  accrued  interest  due under the loan from the
holders of Raven Series D preferred stock will automatically convert into shares
of Series D preferred stock immediately prior to the closing of the transaction.
This conversion is reflected in the current exchange ratio agreed to between the
two companies.

Rationale and Pipeline

"We  believe  that the  proposed  merger of Raven and VaxGen  will  create a new
company that can deliver  value through its  promising  pipeline and  technology
platforms in one of the most scientifically and commercially  promising areas of
drug  development,"  said George F.  Schreiner,  M.D.,  Ph.D.,  chief  executive
officer of Raven biotechnologies.

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"We expect that the transaction  will allow the new company to accomplish  three
objectives:  first,  to  initiate  Phase 2 clinical  trails for RAV12,  our lead
oncology  product;  second,  to move our lead antibodies  targeting  cancer stem
cells into the clinic;  and third, to advance our discovery  platforms in cancer
stem  cell  biology.  We  further  expect  that  the  new  company  will be well
positioned  to pursue  collaborations  with  pharmaceutical  companies and other
strategic alliances."

James P. Panek,  VaxGen's president and chief executive  officer,  said: "During
the past 10 months, VaxGen evaluated a wide range of strategic  alternatives and
determined   that  Raven's  strong   pipeline,   technology  and   complementary
capabilities distinguished it from the alternatives.  We are confident that this
proposed  transaction  with Raven will  achieve  our goal to build value for our
stockholders through the creation of a broadly based biotechnology  company with
a promising future."

The combined  company's product pipeline will have one compound for major cancer
indications  in  clinical  development,  four  oncology  product  candidates  in
preclinical development, and a substantial library of antibodies to novel cancer
antigens.  This library includes  antibodies to tumor stem cells and conditioned
cell immunogens,  which are undergoing pre-clinical  screening.  The new company
would expect to file at least one additional IND in 2009.

Organization, Management and Board of Directors

Both  companies  separately  expect to  undertake  restructuring  efforts in the
fourth quarter to conserve cash resources. The combined company will be based in
Raven's offices in South San Francisco.

Upon  closing,  Dr.  Schreiner  will serve as CEO and a director of the combined
company.  Mr.  Panek will  assume  the title of  president  and chief  operating
officer and will serve as a director.  Other executive  officers of the combined
company will be Matthew J. Pfeffer,  chief financial officer;  Jennie P. Mather,
Ph.D.,  chief  scientific  officer;  Stanford J. Stewart,  M.D., vice president,
clinical  research;  Gordon  A.  Vehar,  Ph.D.,  vice  president,

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research and  development;  and Piers Whitehead,  vice president,  corporate and
business development.

At the closing,  the  combined  company's  board of directors  will include four
members from VaxGen's current board of directors and three from Raven's.  VaxGen
directors who will serve on the new board are Randall L-W. Caudill, D.Phil., who
will  continue as  chairman of the board;  Franklin  M.  Berger,  CFA;  Myron M.
Levine, M.D.; and Mr. Panek. The Raven directors who will serve on the board are
William  D.  Young,  Dr.  Schreiner,  and  Michael  Kranda,  who  will  serve as
vice-chairman.

VaxGen was advised by Lazard and Cooley  Godward  Kronish LLP. Raven was advised
by Montgomery & Co., LLC and Latham & Watkins LLP.

Conference Call

A joint  conference call will be held at 8:00 a.m. EST on Tuesday,  November 13,
2007 to  discuss  the  proposed  merger and the  business  and  strategy  of the
combined company. The call may be accessed through the following means.

Domestic callers: 800-366-7640.
Domestic replay: 800-405-2236 or 303-590-3000;  pass-code 11102242#
International callers: 303-262-2051
International replay: 303-590-3000; pass-code 11102242#

About VaxGen

VaxGen is a biopharmaceutical company based in South San Francisco,  California.
The company owns a  state-of-the-art  biopharmaceutical  manufacturing  facility
with a 1,000-liter bioreactor that can be used to make cell culture or microbial
biologic products. For more information,  please visit the company's web site at
www.vaxgen.com.

About Raven

Raven biotechnologies, inc. is a privately held biotechnology company focused on
the development of monoclonal antibody therapeutics for treating cancer. Raven's
lead  product  candidate,  RAV12,  targets  adenocarcinomas  and is in  clinical
development  for the treatment of  gastrointestinal  and other  cancers.  Raven,
which is based in South  San  Francisco,  California,  has  identified  multiple
candidate  therapeutic MAbs for many cancer  indications  including lung, colon,
pancreatic, prostate, breast, brain, and ovarian

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cancer.   Please  visit   www.ravenbio.com  for  more  information  about  Raven
biotechnologies inc.

Note:  This  press  release  contains  "forward-looking  statements"  within the
meaning  of  the  federal  securities  laws.  These  forward-looking  statements
include, without limitation, statements regarding each company's ability to meet
the  conditions  necessary  to  close  this  transaction,  failure  of  VaxGen's
shareholders  to approve the merger,  the  ability to complete  the  transaction
contemplated by this  communication in a timely fashion,  the risk that VaxGen's
and  Raven's  business  operations  will  not be  integrated  successfully;  the
combined company's inability to further identify, develop and achieve commercial
success for products and  technologies;  the combined  company's ability to meet
milestones  as  planned;  and the risk  that the  combined  company's  financial
resources  will  be  insufficient  to  meet  the  combined   company's  business
objectives.  These statements are subject to risks and uncertainties  that could
cause actual  results and events to differ  materially  from those  anticipated.
Additional  information  concerning these and other risk factors is contained in
VaxGen Form 10-K for the year ended  December 31, 2006 and most  recently  filed
Form10-Q.   Readers  are  cautioned  not  to  place  undue   reliance  on  these
forward-looking  statements  that  speak  only as of the  date of this  release.
VaxGen and Raven undertake no obligation to update publicly any  forward-looking
statements to reflect new information,  events, or circumstances  after the date
of this release except as required by law.

Additional Information and Where to Find It

VaxGen intends to file a registration statement on Form S-4, and a related proxy
statement/prospectus,  in  connection  with the merger.  Investors  and security
holders are urged to read the registration statement on Form S-4 and the related
proxy/prospectus  when they become available because they will contain important
information  about the merger  transaction.  Investors and security  holders may
obtain  free  copies of these  documents  (when  they are  available)  and other
documents filed with the SEC at the SEC's web site at www.sec.gov.  In addition,
investors  and security  holders may obtain free copies of the  documents  filed
with the SEC by  contacting  VaxGen  Investor  Relations  at the email  address:
ir@vaxgen.com.

This communication  shall not constitute an offer to sell or the solicitation of
an offer to sell or the  solicitation  of an  offer to buy any  securities,  nor
shall there be any sale of securities in any  jurisdiction  in which such offer,
solicitation or sale would be unlawful prior to  registration  or  qualification
under the securities  laws of any such  jurisdiction.  No offering of securities
shall be made  except  by means of a  prospectus  meeting  the  requirements  of
Section 10 of the Securities Act of 1933, as amended.

VaxGen,  Raven and their  respective  directors  and  executive  officers may be
deemed to be participants in the  solicitation of proxies from the  stockholders
of VaxGen in connection with the merger transaction.  Information  regarding the
special  interests  of these  directors  and  executive  officers  in the merger
transaction  will be included  in the proxy  statement/prospectus  of  described
above.  Additional information regarding the directors and executive officers of
VaxGen is also included in VaxGen's preliminary proxy  statement

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for its 2007  Annual  Meeting  of  Stockholders  which was filed with the SEC on
November 9, 2007 and its Annual Report on Form 10-K for the year ended  December
31, 2006,  which was filed with the SEC on August 30, 2007.  These documents are
available free of charge at the SEC's web site at www.sec.gov  and from Investor
Relations at VaxGen as described above.

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