As filed with the Securities and Exchange Commission on August 27, 2001
                                                    Registration No. 333-_______
                                                    ============================
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM S-3
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933
                           --------------------------

                                 EXELIXIS, INC.
             (Exact name of registrant as specified in its charter)



                                                               
            DELAWARE                             8731                    04-3257395
(State or other jurisdiction of       (Primary Standard Industrial    (I.R.S. Employer
 incorporation or organization)        Classification Code Number)   Identification No.)


                                 170 HARBOR WAY
                                  P.O. BOX 511
                          SOUTH SAN FRANCISCO, CA 94083
                                  (650) 837-7000
    (Address, including zip code, and telephone number, including area code, of
                    registrant's principal executive offices)
                              ____________________
                            GEORGE A. SCANGOS, PH.D.
                      PRESIDENT AND CHIEF EXECUTIVE OFFICER
                                 EXELIXIS, INC.
                                 170 HARBOR WAY
                                  P.O. BOX 511
                      SOUTH SAN FRANCISCO, CALIFORNIA 94083
                                 (650) 837-7000
  (Name, address, including zip code, and telephone number, including area code,
                              of agent for service)
                              ____________________
                                   Copies to:
                              ROBERT L. JONES, ESQ.
                              GIANNA M. BOSKO, ESQ.
                               COOLEY GODWARD LLP
                              FIVE PALO ALTO SQUARE
                               3000 EL CAMINO REAL
                            PALO ALTO, CA 94306-2155
                                 (650) 843-5000
                              ____________________
        APPROXIMATE DATE OF COMMENCEMENT OF PROPOSED SALE TO THE PUBLIC:
   As soon as practicable after this registration statement becomes effective.
                              _____________________
     If  the  only  securities  being  registered on this Form are being offered
pursuant  to dividend or interest reinvestment plans, please check the following
box. [ ]
     If any of the securities being registered on this Form are to be offered on
a delayed or continuous basis pursuant to Rule 415 under the Securities Act of
1933, other than securities offered only in connection with dividend or interest
reinvestment plans, check the following box. [X]
     If this Form is filed to register additional securities for an offering
pursuant to Rule 462(b) under the Securities Act, please check the following box
and list the Securities Act registration statement number of the earlier
effective registration statement for the same offering. [ ]
     If this Form is a post-effective amendment filed pursuant to Rule 462(c)
under the Securities Act, check the following box and list the Securities Act
registration statement number of the earlier effective registration statement
for the same offering. [ ]
     If delivery of the Prospectus is expected to be made pursuant to Rule 434,
please check the following box. [ ]



                                            CALCULATION OF REGISTRATION FEE
=======================================================================================================================
                                                                                 PROPOSED MAXIMUM
TITLE OF CLASS OF SECURITIES      AMOUNT TO BE      PROPOSED MAXIMUM OFFERING    AGGREGATE OFFERING       AMOUNT OF
 TO BE REGISTERED                 REGISTERED(1)        PRICE PER SHARE (2)           PRICE (2)        REGISTRATION FEE
------------------------------  -----------------  ---------------------------  --------------------  -----------------
                                                                                          
------------------------------  -----------------  ---------------------------  --------------------  -----------------
Common Stock, $0.001 par value     600,600 shares  $                 9,387,378  $              15.63  $           2,347
=======================================================================================================================


(1)     Also includes additional shares of common stock that may be issued as a
        result of stock splits, stock dividends or similar transactions.
(2)     Estimated solely for the purpose of calculating the registration fee in
        accordance with Rule 457 under the Securities Act. The price per share
        and aggregate offering price are based on the average of the high and
        low prices of the registrant's common stock on August 22, 2001 as
        reported on the Nasdaq National  Market.
          THE  REGISTRANT  HEREBY AMENDS THIS REGISTRATION STATEMENT ON THE DATE
OR  DATES  AS  MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT
SHALL  FILE A FURTHER AMENDMENT WHICH SPECIFICALLY STATES THAT THIS REGISTRATION
STATEMENT  SHALL  THEREAFTER BECOME EFFECTIVE IN ACCORDANCE WITH SECTION 8(A) OF
THE  SECURITIES  ACT  OF  1933  OR UNTIL THE REGISTRATION STATEMENT SHALL BECOME
EFFECTIVE  ON  A  DATE THAT THE COMMISSION, ACTING PURSUANT TO SECTION 8(A), MAY
DETERMINE.


======

THE  INFORMATION  IN  THIS  PROSPECTUS  IS NOT COMPLETE AND MAY BE CHANGED.  THE
SELLING  STOCKHOLDERS  MAY  NOT  SELL  THESE  SECURITIES  UNTIL THE REGISTRATION
STATEMENT  FILED  WITH THE SECURITIES AND EXCHANGE COMMISSION IS EFFECTIVE. THIS
PROSPECTUS  IS  NOT  AN  OFFER TO SELL THESE SECURITIES AND IS NOT SOLICITING AN
OFFER  TO  BUY  THESE  SECURITIES  IN  ANY  STATE WHERE THE OFFER OR SALE IS NOT
PERMITTED.

                  SUBJECT TO COMPLETION, DATED AUGUST 27, 2001


                                 600,600 SHARES
                                 EXELIXIS, INC.
                                  COMMON STOCK

The  selling stockholder listed on page 13 is offering up to 600,600 shares of
Exelixis,  Inc. common stock.  We will not receive any proceeds from the sale of
the  shares  by  the  selling  stockholder.

Our  common stock trades on the Nasdaq National Market under the symbol EXEL. On
August 24, 2001, the last reported sale price of our common stock was $17.09 per
share.

The  selling  stockholder  may sell the shares described in this prospectus in a
number  of  different ways and at varying prices.  See "Plan of Distribution" on
page  14  for  more  information  about  how  it  may  sell  its  shares.
We  will  not  be  paying  any  underwriting  discounts  or  commissions in this
offering.

INVESTING  IN  OUR  COMMON  STOCK  INVOLVES  A  HIGH  DEGREE OF RISK.  SEE "RISK
FACTORS"  BEGINNING  ON  PAGE  4.

NEITHER  THE  SECURITIES  AND  EXCHANGE  COMMISSION  NOR  ANY  STATE  SECURITIES
COMMISSION  HAS  APPROVED  OR DISAPPROVED THESE SECURITIES OR DETERMINED IF THIS
PROSPECTUS  IS  TRUTHFUL  OR  COMPLETE.  ANY REPRESENTATION TO THE CONTRARY IS A
CRIMINAL  OFFENSE.

__________  __,  2001.


                                TABLE OF CONTENTS
                                                                            PAGE
                                                                            ----
EXELIXIS                                                                       3
RISK  FACTORS                                                                  4
CAUTIONARY  NOTE  REGARDING  FORWARD-LOOKING  STATEMENTS                      13
USE  OF  PROCEEDS                                                             13
SELLING  STOCKHOLDER                                                          13
PLAN  OF  DISTRIBUTION                                                        14
LEGAL  MATTERS                                                                16
EXPERTS                                                                       16
WHERE  YOU  CAN  FIND  MORE INFORMATION ABOUT EXELIXIS AND THIS OFFERING      16

     This  prospectus is part of a registration statement that we filed with the
Securities  and  Exchange  Commission.  You  should rely only on the information
contained  or  incorporated  by  reference  in  this  prospectus.  We  have  not
authorized  anyone to provide you with information different from that contained
in  this  prospectus.  The  selling stockholder is offering to sell, and seeking
offers  to  buy,  shares  of  our  common stock only in jurisdictions where such
offers  and sales are permitted. The information contained in this prospectus is
accurate  only  as  of  the  date  of this prospectus, regardless of the time of
delivery  of  this  prospectus  or  any  sale  of  our  common  stock.

     Exelixis, Artemis Pharmaceuticals, ACTTAG, the Exelixis, Inc. logos and all
other Exelixis product and service names are registered trademarks or trademarks
of  Exelixis,  Inc. in the U.S. and in other selected countries. All other brand
names  or  trademarks  appearing  in  this  prospectus are the property of their
respective  holders.


                                    EXELIXIS
     We  believe  that  we  are  a  leader  in  the  discovery and validation of
high-quality novel targets for several major human diseases, and a leader in the
discovery  of  potential  new  drug therapies, specifically for cancer and other
proliferative  diseases.  Our  mission  is  to  develop  proprietary products by
leveraging  our  integrated discovery platform to increase the speed, efficiency
and  quality  of  pharmaceutical  and  agricultural  product  discovery  and
development.

     Through  our  expertise  in  biology  and  drug  discovery,  built  upon  a
foundation  of  comparative  genomics  and model system genetics, we are able to
find  new  drug  targets  that  we  believe  would be difficult or impossible to
uncover  using  other  experimental  approaches.  Our  pharmaceutical  research
identifies novel genes and proteins expressed by those genes that, when changed,
either  decrease  or  increase  the  activity in a specific disease pathway in a
therapeutically  relevant  manner.  These  genes  and  proteins represent either
potential  product  targets  or drugs that may treat disease, or prevent disease
initiation  or  progression.

     Specifically  in  cancer,  the  remarkable evolutionary conservation of the
biochemical  pathways between humans and "lower" organisms strongly supports the
use  of simple model systems, such as fruit flies, nematode worms, zebrafish and
mice  to  identify  key  members  of  critical  cancer pathways that can then be
targeted for drug discovery. We expect to develop new cancer drugs by exploiting
the  underlying  "genetic  liabilities" of tumor cells to provide specificity in
targeting  these  cells for destruction, while leaving normal cells unharmed. We
have  discovered  and  are  further  developing  a number of small molecule drug
targets  in  addition  to  monoclonal antibody drug targets. Molecules developed
against  these  targets  may  selectively kill cancer cells while leaving normal
cells  unharmed,  and  may  provide  alternatives  to  current cancer therapies.

     While  our proprietary programs focus on drug discovery and development, we
believe  that  our proprietary technologies are valuable to all other industries
whose products can be enhanced by an understanding of DNA or proteins, including
the  agrochemical,  agricultural  and  diagnostic  industries.  Many  of  these
industries  have  shorter  product  development  cycles  and lower risk than the
pharmaceutical  industry,  while  at  the same time generating significant sales
with  double-digit  product  margins.  By  partnering  with leading companies in
multiple  industries,  we  are able to diversify our business risk, while at the
same  time  maximizing  our  future  revenue  stream.

     We  are a Delaware corporation. Our principal executive offices are located
at  170  Harbor  Way,  South  San Francisco, California 94080, and our telephone
number  is  (650) 837-7000. In this prospectus, "Exelixis," "we," "us" and "our"
refer  to  Exelixis,  Inc.,  unless  the  context  otherwise  requires.


                                  RISK FACTORS
     You  should  carefully  consider the following risk factors, in addition to
other  information  included  or  incorporated  by reference in this prospectus,
before making an investment decision. The risks described below are not the only
risks  we face. Additional risks that we do not yet know of or that we currently
think  are  immaterial  may  also  impair our business operations. If any of the
events  or  circumstances  described in the following risks actually occurs, our
business may suffer, the trading price of our common stock could decline and you
may  lose  all  or  part  of  your  investment.

WE  HAVE A HISTORY OF NET LOSSES. WE EXPECT TO CONTINUE TO INCUR NET LOSSES, AND
WE  MAY  NOT  ACHIEVE  OR  MAINTAIN  PROFITABILITY.

     We  have incurred net losses each year since our inception, including a net
loss  of  approximately $36.4 million for the six months ended June 30, 2001. As
of  that date, we had an accumulated deficit of approximately $166.5 million. We
expect  these  losses  to  continue  and  anticipate  negative cash flow for the
foreseeable  future.  The  size of these net losses will depend, in part, on the
rate of growth, if any, in our license and contract revenues and on the level of
our  expenses.  Our  research  and  development  expenditures  and  general  and
administrative  costs have exceeded our revenues to date, and we expect to spend
significant  additional  amounts  to  fund  research and development in order to
enhance our core technologies and undertake product development. As a result, we
expect  that our operating expenses will increase significantly in the near term
and,  consequently,  we will need to generate significant additional revenues to
achieve  profitability.  Even  if  we  do  increase  our  revenues  and  achieve
profitability,  we  may  not  be  able  to  sustain  or  increase profitability.

WE WILL NEED ADDITIONAL CAPITAL IN THE FUTURE, WHICH MAY NOT BE AVAILABLE TO US.
     Our  future  capital  requirements  will be substantial, and will depend on
     many  factors  including:
     -  payments  received  under  collaborative  agreements;
     -  the progress and scope of our collaborative and independent research and
        development  projects;
     -  our  ability to successfully continue development of a recently acquired
        cancer  compound;
     -  our  need to expand our other proprietary product development efforts as
        well  as  develop manufacturing and marketing capabilities to
        commercialize products; and
     -  the  filing,  prosecution  and  enforcement  of  patent  claims.

     We  anticipate  that  our  current  cash  and  cash equivalents, short-term
investments  and  funding  to  be  received from collaborators will enable us to
maintain  our  currently  planned  operations  for  at least the next two years.
Changes  to  our  current  operating  plan  may  require us to consume available
capital  resources  significantly  sooner than we expect. For example, our newly
acquired  cancer  product from our recent relationship with Bristol-Myers Squibb
will  require  significant  resources  for  development  that  were  not  in our
operational  plans  prior  to acquiring the cancer product.  We may be unable to
raise  sufficient  additional capital when we need it, on favorable terms, or at
all.  If  our  capital  resources  are  insufficient  to  meet  future  capital
requirements,  we  will  have  to  raise additional funds. The sale of equity or
convertible  debt  securities in the future may be dilutive to our stockholders,
and  debt  financing  arrangements  may  require us to pledge certain assets and
enter  into  covenants  that  would  restrict  our  ability  to  incur  further
indebtedness.  If we are unable to obtain adequate funds on reasonable terms, we
may  be  required  to  curtail  operations  significantly  or to obtain funds by
entering  into  financing,  supply  or  collaboration agreements on unattractive
terms.

DIFFICULTIES WE MAY ENCOUNTER MANAGING OUR GROWTH MAY DIVERT RESOURCES AND LIMIT
OUR  ABILITY  TO  SUCCESSFULLY  EXPAND  OUR  OPERATIONS.

     We  have  experienced  a  period  of  rapid and substantial growth that has
placed,  and  our  anticipated  growth  in  the future will continue to place, a
strain  on  our administrative and operational infrastructure. As our operations
expand,  we  expect  that  we  will need to manage multiple locations, including
additional  locations outside of the United States, and additional relationships
with  various  collaborative  partners,  suppliers  and other third parties. Our
ability  to manage our operations and growth effectively requires us to continue
to improve our operational, financial and management controls, reporting systems
and procedures. We may not be able to successfully implement improvements to our
management  information and control systems in an efficient or timely manner and
may  discover  deficiencies  in  existing  systems  and  controls.  In addition,
acquisitions  involve  the  integration  of  different  financial and management
reporting  systems.  We  may  not  be  able  to  successfully  integrate  the
administrative  and  operational  infrastructure  without significant additional
improvements  and  investments  in  management  systems  and  procedures.

WE ARE DEPENDENT ON OUR COLLABORATIONS WITH MAJOR COMPANIES. IF WE ARE UNABLE TO
ACHIEVE  MILESTONES, DEVELOP PRODUCTS OR RENEW OR ENTER INTO NEW COLLABORATIONS,
OUR  REVENUES MAY DECREASE AND OUR ACTIVITIES MAY FAIL TO LEAD TO COMMERCIALIZED
PRODUCTS.

     Substantially  all  of  our  revenues  to  date  have  been  derived  from
collaborative  research  and  development agreements. Revenues from research and
development  collaborations  depend upon continuation of the collaborations, the
achievement  of  milestones and royalties derived from future products developed
from  our  research.  If we are unable to successfully achieve milestones or our
collaborators fail to develop successful products, we will not earn the revenues
contemplated  under  such  collaborative  agreements.  In  addition, some of our
collaborations  are  exclusive  and  preclude  us  from entering into additional
collaborative  arrangements  with  other  parties  in  the  area  or  field  of
exclusivity.

     We  currently have continuing collaborative research agreements with Bayer,
Bristol-Myers  Squibb  (two  agreements),  Dow AgroSciences, Aventis and Protein
Design  Labs.  Our  current  collaborative  agreement with Bayer is scheduled to
expire in 2008, after which it will automatically be extended for one-year terms
unless  terminated  by  either party upon 12-month written notice. Our agreement
permits  Bayer  to terminate our collaborative activities prior to 2008 upon the
occurrence  of  specified  conditions,  such  as  the  failure  to  agree on key
strategic  issues  after  a  period  of  years or the acquisition of Exelixis by
certain  specified  third  parties.  In  addition, our agreements with Bayer are
subject  to termination at an earlier date if two or more of our Chief Executive
Officer, Chief Scientific Officer, Agricultural Biotechnology Program Leader and
Chief Informatics Officer cease to have a relationship with us within six months
of  each  other  and we are unable to find replacements acceptable to Bayer. The
first  of  our  collaborative  agreements  with  Bristol-Myers Squibb expires in
September  2002.  The  funded  research  term  of  the  second  collaborative
arrangement,  entered into in July 2002, expires in July 2005. Our collaborative
agreement with Dow AgroSciences is scheduled to expire in July 2003, after which
Dow  AgroSciences  has the option to renew on an annual basis. Our collaborative
research  arrangement  with Aventis is scheduled to expire in June 2004. Aventis
has  the  right  to  terminate  the research arrangement prior to the expiration
date,  provided that it pays the annual research funding amount due for the year
following  termination.  Thereafter,  the  arrangement  renews  annually  unless
Aventis terminates automatic renewal prior to the scheduled date of renewal. The
Aventis  arrangement  is  conducted  through  a  limited  liability  company,
Agrinomics,  which  is  owned  equally  by  Aventis  and  Exelixis.  Aventis may
surrender  its  interest  in  Agrinomics  and  terminate  the  related  research
collaboration  prior  to  the  scheduled  expiration  upon  the  payment  of the
subsequent  year's  funding  commitment. Bayer and Aventis recently announced an
exclusive  negotiation  period for the purchase of Aventis by Bayer. We have not
been  advised  of the status of those discussions nor are we able to predict the
impact  of such an acquisition of Aventis, if the acquisition were to occur. Our
agreement  with  Protein Design Labs is scheduled to expire in May 2003. Protein
Design  Labs  has  a  unilateral  right to renew for additional 12 and six month
periods  thereafter.  The  five-year  term  of  the  convertible promissory note
entered into as part of this arrangement is unaffected by whether or not Protein
Design  Labs  renews.  If these existing agreements are not renewed or if we are
unable  to  enter  into  new collaborative agreements on commercially acceptable
terms,  our  revenues and product development efforts may be adversely affected.

     We recently announced the reacquisition, effective February 2002, of future
rights  to  research  programs  in metabolism and Alzheimer's disease previously
licensed  exclusively  to  Pharmacia  Corporation.  The  existing agreement with
Pharmacia  will  terminate  as  of  that  date.  Pharmacia will retain rights to
targets  under  the existing agreement selected prior to the reacquisition date,
subject  to  the payment of milestones for certain of those targets selected and
royalties  for future development of products against or using those targets but
will  have  no  other  obligations  to  make  payments to the Company, including
approximately $9.0 million in annual funding that would otherwise be payable for
two  years if the Company had not elected to reacquire rights to the research at
this  time. Although we anticipate entering into future collaborations involving
either or both of these programs, there can be no assurance that we will be able
to  enter  into  new  collaborative  agreements or that such collaborations will
provide  revenues  equal  to  or  exceeding those otherwise obtainable under the
Pharmacia  collaboration.

CONFLICTS  WITH  OUR  COLLABORATORS  COULD  JEOPARDIZE  THE  OUTCOME  OF  OUR
COLLABORATIVE  AGREEMENTS  AND  OUR  ABILITY  TO  COMMERCIALIZE  PRODUCTS.

     We  intend to conduct proprietary research programs in specific disease and
agricultural product areas that are not covered by our collaborative agreements.
Our  pursuit  of opportunities in agricultural and pharmaceutical markets could,
however, result in conflicts with our collaborators in the event that any of our
collaborators takes the position that our internal activities overlap with those
areas  that  are  exclusive  to  our  collaborative agreements, and we should be
precluded  from  such  internal  activities.  Moreover,  disagreements  with our
collaborators  could  develop  over  rights  to  our  intellectual  property. In
addition,  our  collaborative  agreements  may have provisions that give rise to
disputes  regarding the rights and obligations of the parties. Any conflict with
our collaborators could lead to the termination of our collaborative agreements,
delay collaborative activities, reduce our ability to renew agreements or obtain
future collaboration agreements or result in litigation or arbitration and would
negatively  impact  our  relationship  with  existing  collaborators.

     We have limited or no control over the resources that our collaborators may
choose to devote to our joint efforts. Our collaborators may breach or terminate
their  agreements  with  us  or  fail  to  perform their obligations thereunder.
Further,  our collaborators may elect not to develop products arising out of our
collaborative  arrangements  or  may  fail to devote sufficient resources to the
development,  manufacture,  market  or  sale  of  such  products. Certain of our
collaborators  could  also  become  our  competitors  in  the  future.  If  our
collaborators  develop  competing  products,  preclude  us  from  entering  into
collaborations  with  their  competitors,  fail  to  obtain necessary regulatory
approvals,  terminate  their  agreements  with  us prematurely or fail to devote
sufficient  resources  to the development and commercialization of our products,
our  product  development  efforts  could  be  delayed  and  may fail to lead to
commercialized  products.

WE  ARE  DEPLOYING  UNPROVEN  TECHNOLOGIES,  AND  WE  MAY NOT BE ABLE TO DEVELOP
COMMERCIALLY  SUCCESSFUL  PRODUCTS.

     You  must  evaluate  us  in  light  of  the  uncertainties and complexities
affecting  a  biotechnology  company.  Our  technologies  are still in the early
stages  of  development. Our research and operations thus far have allowed us to
identify  a  number  of product targets for use by our collaborators and our own
internal  development  programs.  We are not certain, however, of the commercial
value  of  any of our current or future targets, and we may not be successful in
expanding  the  scope  of  our  research  into  new  fields of pharmaceutical or
pesticide  research,  or other agricultural applications such as enhancing plant
traits  to  produce  superior  crop  yields,  disease  resistance  or  increased
nutritional  content.  Significant research and development, financial resources
and  personnel  will  be  required  to  capitalize  on  our  technology, develop
commercially  viable  products and obtain regulatory approval for such products.

WE  HAVE  NO  EXPERIENCE IN DEVELOPING, MANUFACTURING AND MARKETING PRODUCTS AND
MAY  BE  UNABLE  TO  COMMERCIALIZE  PROPRIETARY  PRODUCTS.

     We  recently  acquired  a  development  compound, an analog to rebeccamycin
("Rebeccamycin"),  directed  against  cancer  under  our  recent  collaborative
arrangement  with Bristol-Myers Squibb.  Clinical development of Rebeccamycin to
date  has  been  conducted  by  the  National  Cancer Institute, or the NCI, and
manufacturing  of  this  product  has  been  the responsibility of Bristol-Myers
Squibb.  Rebeccamycin  has recently completed Phase I clinical studies and is in
Phase  I  and early Phase II clinical trials being conducted by the NCI.  We are
currently  in  negotiations  with  the  NCI  to  use the results of the clinical
studies  they  have  conducted  and  are  conducting  in order to determine what
additional studies, if any, will be conducted by the NCI or us.  There can be no
assurance  that  we  will successfully agree upon further development plans, the
respective  rights and obligations of the parties to conduct additional clinical
studies  or  the timing of such studies.  In addition, there can be no assurance
that  the  clinical  studies  conducted  to  date  will support further clinical
development  or  be  accepted  by  the  Food and Drug Administration, or FDA, in
conjunction  with  any application for product approval submitted to the FDA for
Rebeccamycin.  Moreover, although Bristol-Myers Squibb has provided the NCI with
sufficient  quantities  of  Rebeccamycin to complete the existing Phase I and II
clinical studies, development necessary for further clinical studies and product
approval  will  require us to either develop internal manufacturing capabilities
or  retain  a  third  party  to  manufacture  the product.  In addition, we have
recently  hired a new Senior Vice President responsible for clinical development
of  this product, as well as any new potential products that we may develop.  As
a  result,  we have limited experience in clinical development and no experience
in  manufacturing  potential  drug  products.  Accordingly,  the  development of
Rebeccamycin  is  subject to significant risk and uncertainty, particularly with
respect  to  our  ability  to  successfully  develop,  manufacture  and  market
Rebeccamycin  as  a  product.

     With respect to products developed against our proprietary drug targets, we
will  rely  on  our collaborators to develop and commercialize products based on
our  research and development efforts. We have limited or no experience in using
the targets that we identify to develop our own proprietary products. Our recent
success in applying our drug development capabilities to our proprietary targets
in  cancer  are  subject  to significant risk and uncertainty, particularly with
respect  to  our  ability  to  meet  currently estimated timelines and goals for
completing  preclinical  development  efforts  and filing an Investigational New
Drug  Application,  or  IND,  for  compounds  developed.  In  order  for  us  to
commercialize  products, we would need to significantly enhance our capabilities
with  respect  to product development, and establish manufacturing and marketing
capabilities,  either directly or through outsourcing or licensing arrangements.
We  may  not  be  able to enter into such outsourcing or licensing agreements on
commercially  reasonable  terms,  or  at  all.

SINCE  OUR  TECHNOLOGIES  HAVE  MANY  POTENTIAL APPLICATIONS AND WE HAVE LIMITED
RESOURCES,  OUR  FOCUS  ON  A  PARTICULAR  AREA  MAY  RESULT  IN  OUR FAILURE TO
CAPITALIZE  ON  MORE  PROFITABLE  AREAS.

     We  have  limited  financial  and managerial resources. This requires us to
focus on product candidates in specific industries and forego opportunities with
regard  to  other products and industries. For example, depending on our ability
to  allocate  resources,  a decision to concentrate on a particular agricultural
program  may  mean  that  we will not have resources available to apply the same
technology  to a pharmaceutical project. While our technologies may permit us to
work  in  both  areas,  resource commitments may require trade-offs resulting in
delays in the development of certain programs or research areas, which may place
us  at  a  competitive disadvantage. Our decisions impacting resource allocation
may  not  lead  to  the development of viable commercial products and may divert
resources  from  more  profitable  market  opportunities.  Moreover,  our recent
acquisition  of  Rebeccamycin will require that resources and management time be
directed  to  clinical  development and manufacturing of this potential product.
There  can  be  no assurance that allocating resources and time to these efforts
will  allow us to remain competitive in existing programs and potential areas of
future research.  The resources dedicated to the development of Rebeccamycin may
limit  or hinder our ability to meet currently estimated timelines and goals for
completing preclinical development efforts and filing an IND for our proprietary
compounds.

OUR  COMPETITORS  MAY DEVELOP PRODUCTS AND TECHNOLOGIES THAT MAKE OURS OBSOLETE.

     The  biotechnology  industry  is  highly fragmented and is characterized by
rapid  technological  change.  In  particular,  the  area  of gene research is a
rapidly  evolving field. We face, and will continue to face, intense competition
from  large  biotechnology  and  pharmaceutical  companies,  as well as academic
research  institutions,  clinical reference laboratories and government agencies
that  are  pursuing research activities similar to ours. Some of our competitors
have  entered  into  collaborations  with  leading  companies  within our target
markets,  including  some of our existing collaborators. Our future success will
depend  on  our  ability  to  maintain  a  competitive  position with respect to
technological  advances.

     Any  products  that  are developed through our technologies will compete in
highly  competitive  markets.  Further, our competitors may be more effective at
using  their  technologies  to  develop  commercial  products.  Many  of  the
organizations  competing with us have greater capital resources, larger research
and  development  staffs and facilities, more experience in obtaining regulatory
approvals  and  more extensive product manufacturing and marketing capabilities.
As a result, our competitors may be able to more easily develop technologies and
products  that  would  render  our  technologies  and products, and those of our
collaborators,  obsolete  and  noncompetitive.

IF  WE ARE UNABLE TO ADEQUATELY PROTECT OUR INTELLECTUAL PROPERTY, THIRD PARTIES
MAY  BE  ABLE TO USE OUR TECHNOLOGY, WHICH COULD ADVERSELY AFFECT OUR ABILITY TO
COMPETE  IN  THE  MARKET.

     Our  success  will  depend  in  part  on  our ability to obtain patents and
maintain  adequate  protection  of  the  intellectual  property  related  to our
technologies  and  products.  The  patent  positions of biotechnology companies,
including our patent position, are generally uncertain and involve complex legal
and  factual  questions.  We  will  be able to protect our intellectual property
rights  from  unauthorized  use  by  third  parties  only to the extent that our
technologies  are  covered  by  valid and enforceable patents or are effectively
maintained  as  trade secrets. The laws of some foreign countries do not protect
intellectual  property  rights  to  the same extent as the laws of the U.S., and
many companies have encountered significant problems in protecting and defending
such  rights  in  foreign  jurisdictions.  We will continue to apply for patents
covering our technologies and products as and when we deem appropriate. However,
these  applications  may  be challenged or may fail to result in issued patents.
Our  existing  patents  and any future patents we obtain may not be sufficiently
broad  to  prevent  others  from  practicing our technologies or from developing
competing  products.  Furthermore,  others  may independently develop similar or
alternative  technologies or design around our patents. In addition, our patents
may  be  challenged,  invalidated  or  fail  to  provide us with any competitive
advantages.

     We  rely  on  trade  secret protection for our confidential and proprietary
information.  We  have  taken  security  measures  to  protect  our  proprietary
information  and  trade  secrets,  but  these  measures may not provide adequate
protection.  While  we  seek  to protect our proprietary information by entering
into  confidentiality  agreements with employees, collaborators and consultants,
we  cannot assure you that our proprietary information will not be disclosed, or
that we can meaningfully protect our trade secrets. In addition, our competitors
may  independently  develop  substantially equivalent proprietary information or
may  otherwise  gain  access  to  our  trade  secrets.

LITIGATION  OR  THIRD  PARTY  CLAIMS OF INTELLECTUAL PROPERTY INFRINGEMENT COULD
REQUIRE  US TO SPEND SUBSTANTIAL TIME AND MONEY AND ADVERSELY AFFECT OUR ABILITY
TO  DEVELOP  AND  COMMERCIALIZE  PRODUCTS.

     Our  commercial  success depends in part on our ability to avoid infringing
patents  and proprietary rights of third parties, and not breaching any licenses
that  we  have  entered into with regard to our technologies. Other parties have
filed,  and in the future are likely to file, patent applications covering genes
and  gene fragments, techniques and methodologies relating to model systems, and
products  and  technologies  that  we  have  developed  or intend to develop. If
patents  covering  technologies required by our operations are issued to others,
we  may  have to rely on licenses from third parties, which may not be available
on  commercially  reasonable  terms,  or  at  all.

     Third  parties  may  accuse  us  of  employing their proprietary technology
without authorization. In addition, third parties may obtain patents that relate
to  our  technologies  and  claim  that use of such technologies infringes these
patents.  Regardless  of  their  merit,  such  claims  could require us to incur
substantial  costs,  including  the  diversion  of  management  and  technical
personnel,  in  defending  ourselves  against  any  such claims or enforcing our
patents. In the event that a successful claim of infringement is brought against
us, we may be required to pay damages and obtain one or more licenses from third
parties. We may not be able to obtain these licenses at a reasonable cost, or at
all.  Defense  of  any  lawsuit or failure to obtain any of these licenses could
adversely  affect  our  ability  to  develop  and  commercialize  products.

THE  LOSS  OF  KEY  PERSONNEL  OR THE INABILITY TO ATTRACT AND RETAIN ADDITIONAL
PERSONNEL  COULD  IMPAIR  OUR  ABILITY  TO  EXPAND  OUR  OPERATIONS.

     We  are  highly  dependent  on  the principal members of our management and
scientific  staff,  the  loss  of  whose  services  might  adversely  impact the
achievement  of  our objectives and the continuation of existing collaborations.
In  addition, recruiting and retaining qualified scientific personnel to perform
future  research and development work will be critical to our success. We do not
currently  have sufficient executive management and technical personnel to fully
execute  our  business plan. There is currently a shortage of skilled executives
and employees with technical expertise, and this shortage is likely to continue.
As a result, competition for skilled personnel is intense and turnover rates are
high.  Although  we  believe  we  will be successful in attracting and retaining
qualified  personnel,  competition  for  experienced  scientists  from  numerous
companies,  academic and other research institutions may limit our ability to do
so.

     Our  business  operations  will  require  additional  expertise in specific
industries and areas applicable to products identified and developed through our
technologies.  These  activities  will  require  the  addition of new personnel,
including  management  and technical personnel and the development of additional
expertise  by  existing employees. The inability to attract such personnel or to
develop  this  expertise  could  prevent  us  from expanding our operations in a
timely  manner,  or  at  all.

OUR  COLLABORATIONS  WITH  OUTSIDE  SCIENTISTS MAY BE SUBJECT TO RESTRICTION AND
CHANGE.

     We  work  with  scientific advisors and collaborators at academic and other
institutions  that  assist  us  in  our  research and development efforts. These
scientists are not our employees and may have other commitments that would limit
their  availability  to  us.  Although our scientific advisors and collaborators
generally  agree  not  to  do  competing work, if a conflict of interest between
their  work  for  us and their work for another entity arises, we may lose their
services.  In  addition, although our scientific advisors and collaborators sign
agreements  not  to  disclose  our confidential information, it is possible that
valuable  proprietary  knowledge  may  become  publicly  known  through  them.

OUR  POTENTIAL  THERAPEUTIC  PRODUCTS  ARE  SUBJECT  TO  A LENGTHY AND UNCERTAIN
REGULATORY  PROCESS  THAT  MAY NOT RESULT IN THE NECESSARY REGULATORY APPROVALS,
WHICH  COULD  ADVERSELY  AFFECT  OUR  ABILITY  TO  COMMERCIALIZE  PRODUCTS.

     The FDA must approve any drug or biologic product before it can be marketed
in  the  U.S.  Any  products resulting from our research and development efforts
must  also  be approved by the regulatory agencies of foreign governments before
the  product  can  be  sold  outside  the  U.S. Before a new drug application or
biologics  license  application can be filed with the FDA, the product candidate
must  undergo  extensive  clinical  trials,  which  can  take many years and may
require  substantial  expenditures.  The  regulatory  process  also  requires
preclinical  testing. Data obtained from preclinical and clinical activities are
susceptible  to  varying  interpretations,  which  could delay, limit or prevent
regulatory  approval. In addition, delays or rejections may be encountered based
upon  changes  in  regulatory  policy  for product approval during the period of
product  development  and regulatory agency review. The clinical development and
regulatory  approval  process  is  expensive  and time consuming. Any failure to
obtain  regulatory  approval  could  delay  or  prevent  us from commercializing
products.

     Our  efforts  to  date  have been primarily limited to identifying targets.
Significant  research  and  development  efforts  will  be  necessary before any
products  resulting  from  such  targets  can  be  commercialized. If regulatory
approval is granted to any of our products, this approval may impose limitations
on  the  uses  for  which  a  product  may be marketed. Further, once regulatory
approval  is  obtained,  a  marketed product and its manufacturer are subject to
continual review, and discovery of previously unknown problems with a product or
manufacturer  may  result  in  restrictions  and  sanctions  with respect to the
product,  manufacturer and relevant manufacturing facility, including withdrawal
of  the  product  from  the  market.

SOCIAL  ISSUES  MAY  LIMIT  THE  PUBLIC  ACCEPTANCE  OF  GENETICALLY  ENGINEERED
PRODUCTS,  WHICH  COULD  REDUCE  DEMAND  FOR  OUR  PRODUCTS.

     Although  our  technology  is not dependent on genetic engineering, genetic
engineering  plays  a prominent role in our approach to product development. For
example,  research efforts focusing on plant traits may involve either selective
breeding  or  modification  of  existing  genes in the plant under study. Public
attitudes  may  be influenced by claims that genetically engineered products are
unsafe  for  consumption  or  pose  a danger to the environment. Such claims may
prevent  our genetically engineered products from gaining public acceptance. The
commercial  success  of  our  future  products  will  depend, in part, on public
acceptance  of  the  use  of genetically engineered products including drugs and
plant  and  animal  products.

     The  subject  of  genetically  modified  organisms  has  received  negative
publicity,  which  has  aroused public debate. For example, certain countries in
Europe  are  considering  regulations  that  may ban products or require express
labeling  of  products  that  contain  genetic modifications or are "genetically
modified."  Adverse publicity has resulted in greater regulation internationally
and  trade  restrictions  on imports of genetically altered products. If similar
action  is  taken  in  the  U.S.,  genetic  research  and genetically engineered
products  could  be  subject  to greater domestic regulation, including stricter
labeling  requirements.  To  date,  our  business has not been hampered by these
activities.  However,  such  publicity  in  the  future may prevent any products
resulting from our research from gaining market acceptance and reduce demand for
our  products.

LAWS  AND  REGULATIONS  MAY  REDUCE  OUR  ABILITY TO SELL GENETICALLY ENGINEERED
PRODUCTS  THAT  OUR  COLLABORATORS  OR  WE  DEVELOP  IN  THE  FUTURE.

     Our collaborators or we may develop genetically engineered agricultural and
animal  products.  The  field-testing,  production  and marketing of genetically
engineered  products  are  subject  to  regulation  by federal, state, local and
foreign  governments.  Regulatory  agencies  administering  existing  or  future
regulations  or  legislation  may  prevent  us  from  producing  and  marketing
genetically  engineered  products  in  a  timely  manner or under technically or
commercially  feasible  conditions.  In  addition,  regulatory action or private
litigation  could result in expenses, delays or other impediments to our product
development  programs  and  the  commercialization  of  products.

     The FDA has released a policy statement stating that it will apply the same
regulatory  standards  to  foods  developed  through  genetic  engineering as it
applies  to  foods  developed  through  traditional  plant breeding. Genetically
engineered  food products will be subject to premarket review, however, if these
products raise safety questions or are deemed to be food additives. Our products
may be subject to lengthy FDA reviews and unfavorable FDA determinations if they
raise  questions  regarding  safety  or  our  products  are  deemed  to  be food
additives.

     The  FDA has also announced that it will not require genetically engineered
agricultural products to be labeled as such, provided that these products are as
safe  and  have the same nutritional characteristics as conventionally developed
products.  The  FDA  may  reconsider  or change its policies, and local or state
authorities  may  enact  labeling  requirements,  either  of  which could have a
material  adverse  effect  on our ability or the ability of our collaborators to
develop  and  market  products  resulting  from  our  efforts.

WE  USE  HAZARDOUS  CHEMICALS  AND  RADIOACTIVE  AND BIOLOGICAL MATERIALS IN OUR
BUSINESS. ANY CLAIMS RELATING TO IMPROPER HANDLING, STORAGE OR DISPOSAL OF THESE
MATERIALS  COULD  BE  TIME  CONSUMING  AND  COSTLY.

     Our  research  and  development  processes  involve  the  controlled use of
hazardous  materials, including chemicals, radioactive and biological materials.
Our operations produce hazardous waste products. We cannot eliminate the risk of
accidental  contamination  or  discharge  and  any  resultant  injury from these
materials.  Federal,  state  and  local  laws  and  regulations  govern the use,
manufacture,  storage,  handling  and disposal of hazardous materials. We may be
sued  for  any  injury  or contamination that results from our use or the use by
third  parties  of  these  materials, and our liability may exceed our insurance
coverage  and  our  total  assets.  Compliance  with  environmental  laws  and
regulations  may  be  expensive, and current or future environmental regulations
may  impair  our  research,  development  and  production  efforts.

     In  addition,  our  collaborators may use hazardous materials in connection
with  our  collaborative  efforts.  To our knowledge, their work is performed in
accordance  with  applicable biosafety regulations. In the event of a lawsuit or
investigation,  however,  we  could be held responsible for any injury caused to
persons or property by exposure to, or release of, these hazardous materials use
by  these  parties.  Further,  we may be required to indemnify our collaborators
against  all  damages  and  other  liabilities  arising  out  of our development
activities  or  products  produced  in  connection  with  these  collaborations.

WE  EXPECT  THAT  OUR  QUARTERLY  RESULTS OF OPERATIONS WILL FLUCTUATE, AND THIS
FLUCTUATION  COULD  CAUSE  OUR  STOCK PRICE TO DECLINE, CAUSING INVESTOR LOSSES.

     Our  quarterly operating results have fluctuated in the past and are likely
to  fluctuate  in  the  future.  A  number  of  factors, many of which we cannot
control,  could  subject  our  operating  results and stock price to volatility,
including:
     -  recognition  of  license,  milestone  or  other  fees;
     -  payments  of  licensing  fees  to  third  parties;
     -  acceptance  of  our  technologies  and  platforms;
     -  the  success  rate  of  our  discovery efforts leading to milestones and
        royalties;
     -  the  introduction  of  new  technologies or products by our competitors;
     -  the  timing  and  willingness  of  collaborators  to  commercialize  our
        products;
     -  our  ability  to  enter  into  new  collaborative  relationships;
     -  the  termination  or  non-renewal  of  existing  collaborations;
     -  general  and  industry-specific  economic conditions that may affect our
        collaborators'  research  and  development  expenditures;  and
     -  exposure  to  fluctuations  in  foreign  currency.

     A  large  portion  of  our  expenses,  including  expenses  for facilities,
equipment and personnel, are relatively fixed in the short term. In addition, we
expect  operating  expenses  to  increase  significantly  during  the next year.
Accordingly,  if  our  revenues decline or do not grow as anticipated due to the
expiration  of  existing  contracts  or our failure to obtain new contracts, our
inability  to  meet  milestones  or  other  factors,  we  may  not  be  able  to
correspondingly  reduce  our  operating expenses. Failure to achieve anticipated
levels  of revenues could therefore significantly harm our operating results for
a  particular  fiscal  period.

     Due  to  the  possibility  of fluctuations in our revenues and expenses, we
believe  that  quarter-to-quarter comparisons of our operating results are not a
good indication of our future performance. As a result, in some future quarters,
our operating results may not meet the expectations of stock market analysts and
investors,  which  could  result  in  a  decline  in  the  price  of  our stock.

OUR  STOCK  PRICE  MAY  BE  EXTREMELY  VOLATILE
 .
     We  believe  the  trading  price  of  our  common  stock will remain highly
volatile  and  may fluctuate substantially due to factors such as the following:
     -  the  announcement  of new products or services by us or our competitors;
     -  quarterly  variations  in our or our competitors' results of operations;
     -  failure  to  achieve operating results projected by securities analysts;
     -  changes in earnings estimates or recommendations by securities analysts;
     -  developments  in  the  biotechnology  industry;
     -  acquisitions  of  other  companies  or  technologies;  and
     -  general market conditions and other factors, including factors unrelated
        to  our  operating  performance  or  the  operating  performance  of our
        competitors.  These  factors and fluctuations, as well as general
        economic, political and market conditions, may materially adversely
        affect the market price  of  our  common  stock.

     In  the  past,  following  periods  of  volatility in the market price of a
company's  securities,  securities  class  action  litigation  has  often  been
instituted.  A  securities  class  action  suit  against  us  could  result  in
substantial  costs  and divert management's attention and resources, which could
have  a  material  and  adverse  effect  on  our  business.

WE  ARE  EXPOSED  TO  RISKS  ASSOCIATED  WITH  ACQUISITIONS.
     We  have  made, and may in the future make, acquisitions of, or significant
investments  in,  businesses  with  complementary  products,  services  and/or
technologies.  Acquisitions  involve  numerous risks, including, but not limited
to:
     -  difficulties  and  increased costs in connection with integration of the
        personnel, operations, technologies and  products of acquired companies;
     -  diversion  of  management's  attention  from  other operational matters;
     -  the  potential  loss  of  key  employees  of  acquired  companies;
     -  the  potential  loss  of  key  collaborators  of the acquired companies;
     -  lack  of  synergy,  or  the  inability  to  realize  expected synergies,
        resulting  from  the  acquisition;
     -  exposure  to  fluctuations  in  foreign  currency;
     -  differences  in  foreign laws, business practices, statutes, regulations
        and  tax  provisions;  and
     -  acquired intangible assets becoming impaired as a result of
        technological advancements or worse-than-expected performance of the
        acquired company.

Mergers  and acquisitions are inherently risky, and the inability to effectively
manage these risks could materially and adversely affect our business, financial
condition  and  results  of  operations.

IF PRODUCT LIABILITY LAWSUITS ARE SUCCESSFULLY BROUGHT AGAINST US, WE COULD FACE
SUBSTANTIAL  LIABILITIES  THAT  EXCEED  OUR  RESOURCES.

     We may be held liable if any product our collaborators or we develop causes
injury  or  is found otherwise unsuitable during product testing, manufacturing,
marketing  or  sale.  Although we intend to obtain general liability and product
liability  insurance,  this insurance may be prohibitively expensive, or may not
fully  cover our potential liabilities. Inability to obtain sufficient insurance
coverage  at  an  acceptable  cost  or  to  otherwise  protect ourselves against
potential  product  liability  claims  could  prevent  or  inhibit  the
commercialization  of  products  developed  by  our  collaborators  or  us.

OUR FACILITIES ARE LOCATED NEAR KNOWN EARTHQUAKE FAULT ZONES, AND THE OCCURRENCE
OF  AN  EARTHQUAKE  OR  OTHER  CATASTROPHIC  DISASTER  COULD CAUSE DAMAGE TO OUR
FACILITIES AND EQUIPMENT, WHICH COULD REQUIRE US TO CEASE OR CURTAIL OPERATIONS.

     Given  our  location,  our  facilities  are  vulnerable  to  damage  from
earthquakes.  We  are  also  vulnerable to damage from other types of disasters,
including  fire, floods, power loss, communications failures and similar events.
If  any  disaster  were  to  occur,  our  ability to operate our business at our
facilities would be seriously, or potentially completely, impaired. In addition,
the  unique  nature of our research activities could cause significant delays in
our  programs  and  make  it  difficult  for  us to recover from a disaster. The
insurance  we  maintain  may  not be adequate to cover our losses resulting from
disasters  or  other business interruptions. Accordingly, an earthquake or other
disaster  could  materially  and adversely harm our ability to conduct business.

FUTURE  SALES  OF  OUR  COMMON  STOCK  MAY  DEPRESS  OUR  STOCK  PRICE.

     If our stockholders sell substantial amounts of our common stock (including
shares  issued  upon  the  exercise  of outstanding options and warrants) in the
public  market,  the  market  price of our common stock could fall.  These sales
also  might  make  it  more  difficult  for  us to sell equity or equity-related
securities  in  the  future  at a time and price that we deemed appropriate.  In
October  2000,  a  significant  number  of  shares  of  our common stock held by
existing  stockholders  became freely tradable, subject in some instances to the
volume  and  other  limitations  of  Rule  144.  Sales of these shares and other
shares  of  common  stock  held  by existing stockholders could cause the market
price  of  our  common  stock  to  decline.

SOME  OF  OUR  EXISTING STOCKHOLDERS CAN EXERT CONTROL OVER US, AND MAY NOT MAKE
DECISIONS  THAT  ARE  IN  THE  BEST  INTERESTS  OF  ALL  STOCKHOLDERS.

     Due to their combined stock holdings, our officers, directors and principal
stockholders  (stockholders  holding  more  than  5% of our common stock) acting
together,  may be able to exert significant influence over all matters requiring
stockholder  approval,  including  the  election  of  directors  and approval of
significant corporate transactions. In addition, this concentration of ownership
may  delay or prevent a change in control of our company, even when a change may
be  in  the  best  interests  of our stockholders. In addition, the interests of
these  stockholders  may  not always coincide with our interests as a company or
the interests of other stockholders. Accordingly, these stockholders could cause
us  to  enter  into  transactions  or  agreements  that  you  would not approve.


              CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

     Some of the statements in this prospectus and the documents incorporated by
reference  are  forward-looking  statements.  These  statements are based on our
current  expectations, assumptions, estimates and projections about our business
and  our  industry, and involve known and unknown risks, uncertainties and other
factors  that  may  cause  our  or  our  industry's results, levels of activity,
performance  or  achievement to be materially different from any future results,
levels  of  activity,  performance  or  achievements  expressed or implied in or
contemplated  by  the  forward-looking  statements.  Words  such  as  "believe,"
"anticipate,"  "expect,"  "intend," "plan," "will," "may," "should," "estimate,"
"predict,"  "potential,"  "continue"  or  the  negative  of  such terms or other
similar  expressions,  identify  forward-looking  statements.  In  addition, any
statements that refer to expectations, projections or other characterizations of
future  events  or  circumstances  are  forward-looking  statements.  Our actual
results  could  differ materially from those anticipated in such forward-looking
statements as a result of several factors more fully described under the caption
"Risk  Factors"  and  in  the  documents  incorporated  by  reference.  The
forward-looking  statements  made in this prospectus relate only to events as of
the  date  on  which  the  statements  are  made.

                                 USE OF PROCEEDS

     The  proceeds  from  the  sale of the common stock offered pursuant to this
prospectus  are  solely for the account of the selling stockholder.  We will not
receive  any  proceeds  from  the  sale  of  these  shares  of  common  stock.

                               SELLING STOCKHOLDER
     We  are  registering the shares covered by this prospectus on behalf of the
selling stockholder named in the table below. We issued all of the shares to the
selling  stockholder  in a private placement transaction. We have registered the
shares  to  permit the selling stockholder and its pledgees, donees, transferees
or  other  successors-in-interest  that  receive  their  shares from the selling
stockholder  as  a  gift,  partnership  distribution  or  other non-sale related
transfer  after  the  date  of this prospectus to resell the shares. The selling
stockholder  has  agreed not to offer, sell, contract to sell, pledge, grant any
option  to  purchase,  make  any  short  sale or otherwise dispose of the shares
covered  by  this  prospectus  without  our  consent  until  July  17,  2002.

     The  following  table  sets  forth the name of the selling stockholder, the
number  of  shares  owned  by it, the number of shares that may be offered under
this  prospectus,  the number of shares of our common stock owned by the selling
stockholder  as  of  July 31, 2001, and the number of shares of our common stock
owned  by  the selling stockholder after this offering is completed. On July 17,
2001,  in connection with the issuance of the shares covered by this prospectus,
the selling stockholder entered into a cancer research collaboration and license
agreement  with  us,  and  thus  is one of our corporate partners. The number of
shares  in  the  column  "Number  of Shares Being Offered" represents all of the
shares that the selling stockholder may offer under this prospectus. The selling
stockholder  may  sell  some,  all  or  none of the shares registered hereunder.
Except  for  the  lockup  described  above,  we do not know how long the selling
stockholder will hold the shares before selling them. The shares offered by this
prospectus  may  be  offered  from  time  to  time  by  the selling stockholder.

     Beneficial  ownership  is  determined  in  accordance  with  Rule  13d-3(d)
promulgated  by  the  SEC  under  the  Securities  Exchange Act of 1934.  Unless
otherwise  noted,  none of the share amounts set forth below represent more than
1%  of  our outstanding stock as of July 31, 2001, adjusted as required by rules
promulgated  by  the  SEC. The percentages of shares owned prior to the offering
are based on 49,161,649 shares of our common stock outstanding on July 31, 2001,
giving  effect  to  the sale of 600,600 shares to the selling stockholder in the
private  placement.



                                       SHARES BENEFICIALLY             SHARES BENEFICIALLY
                                       OWNED PRIOR TO THE                OWNED AFTER  THE
                                            OFFERING        NUMBER OF       OFFERING (1)
                                        -----------------  SHARES BEING  ---------------
NAME                                    NUMBER   PERCENT     OFFERED     NUMBER  PERCENT
----------------------------            -------  --------  ------------  ------  -------
                                                                  

Bristol-Myers Squibb Company . . . . .  600,600     1.22%       600,600       0        *



(1)  Does not constitute a commitment to sell any or all of the stated number of
shares  of  common  stock. The number of shares offered shall be determined from
time  to  time  by the selling stockholder at its sole discretion. The number of
shares  to  be owned by the selling stockholder after the offering, assuming the
sale  of  all of the stated number of shares of common stock, will be less than
one percent  of  its  outstanding  shares  after  the  offering.

                              PLAN OF DISTRIBUTION

     The  selling stockholder may sell the shares from time to time. The selling
stockholder  will  act  independently  of  us  in making decisions regarding the
timing,  manner  and  size  of  each  sale. The sales may be made on one or more
exchanges or in the over-the-counter market or otherwise, at prices and at terms
then  prevailing  or  at  prices related to the then current market price, or in
privately  negotiated  transactions.  The  selling  stockholder may effect these
transactions  by  selling  the  shares to or through broker-dealers. The selling
stockholder  may  sell  its  shares  in  one  or  more  of, or a combination of:
     -  a block trade in which the broker-dealer will attempt to sell the shares
     as agent but may position and resell a portion of the block as principal to
     facilitate  the  transaction;
     -  purchases  by a broker-dealer as principal and resale by a broker-dealer
     for  its  account  under  this  prospectus;
     -  an  exchange distribution in accordance with the rules of an exchange; -
     ordinary  brokerage  transactions  and  transactions  in  which  the broker
     solicits  purchasers;  and
     -  privately  negotiated  transactions.

     To the extent required, this prospectus may be amended or supplemented from
time  to  time  to  describe  a  specific  plan  of distribution. If the plan of
distribution involves an arrangement with a broker-dealer for the sale of shares
through  a  block  trade,  special  offering, exchange distribution or secondary
distribution  or  a  purchase by a broker or dealer, the amendment or supplement
will  disclose:
     -  the  name  of  the  selling  stockholder  and  of  the  participating
     broker-dealer(s);
     -  the  number  of  shares  involved;
     -  the  price  at  which  the  shares  were  sold;
     -  the  commissions  paid  or  discounts  or  concessions  allowed  to  the
     broker-dealer(s),  where  applicable;
     -  that  a broker-dealer(s) did not conduct any investigation to verify the
     information  set  out  or incorporated by reference in this prospectus; and
     -  other  facts  material  to  the  transaction.

     The  selling  stockholder  has agreed not to offer, sell, contract to sell,
pledge,  grant  any option to purchase, make any short sale or otherwise dispose
of  the  shares  covered  by  this prospectus without our consent until July 17,
2002. From time to time, the selling stockholder may transfer, pledge, donate or
assign  its shares of common stock to lenders or others and each of such persons
will  be  deemed  to be a "selling stockholder" for purposes of this prospectus.
The  number  of  shares  of  common  stock  beneficially  owned  by  the selling
stockholder  will  decrease  as  and  when  it  takes  such actions. The plan of
distribution  for  the  selling  stockholder's shares of common stock sold under
this  prospectus  will  otherwise remain unchanged, except that the transferees,
pledgees,  donees  or  other  successors will be selling stockholders hereunder.
Upon  being notified by a selling stockholder that a donee or pledgee intends to
sell  more  than  500  shares,  we  will  file  a supplement to this prospectus.


     The  selling  stockholder  may  enter  into  hedging  transactions  with
broker-dealers  in  connection with distributions of the shares or otherwise. In
these  transactions,  broker-dealers  may engage in short sales of the shares in
the  course  of  hedging the positions they assume with the selling stockholder.
The  selling  stockholder also may sell shares short and redeliver the shares to
close  out  short  positions.  The  selling stockholder may enter into option or
other  transactions  with  broker-dealers  that  require  the  delivery  to  the
broker-dealer  of  the  shares.  The  broker-dealer may then resell or otherwise
transfer the shares under this prospectus. The selling stockholder also may loan
or  pledge  the shares to a broker-dealer. The broker-dealer may sell the loaned
shares,  or  upon  a default the broker-dealer may sell the pledged shares under
this  prospectus.

     In  effecting  sales, broker-dealers engaged by the selling stockholder may
arrange  for  other broker-dealers to participate in the resales. Broker-dealers
or  agents  may  receive  compensation  in the form of commissions, discounts or
concessions  from  the  selling  stockholder.  Broker-dealers or agents may also
receive  compensation  from  the  purchasers  of the shares for whom they act as
agents  or  to  whom  they  sell  as  principals,  or both. Compensation as to a
particular broker-dealer might be in excess of customary commissions and will be
in  amounts  to  be  negotiated  in connection with the sale. A broker-dealer or
agent  and  any other participating broker-dealer or the selling stockholder may
be  deemed  to  be  an  "underwriter" within the meaning of Section 2(11) of the
Securities  Act  in  connection  with  sales  of  the  shares.  Accordingly, any
commission, discount or concession received by them and any profit on the resale
of  the  shares  purchased by them may be deemed to be underwriting discounts or
commissions  under  the  Securities  Act. Because the selling stockholder may be
deemed  to  be  an  "underwriter"  within  the  meaning  of Section 2(11) of the
Securities  Act,  the  selling  stockholder  will  be  subject to the prospectus
delivery requirements of the Securities Act. In addition, any securities covered
by  this  prospectus  that qualify for sale under Rule 144 promulgated under the
Securities Act may be sold under Rule 144 rather than under this prospectus. The
selling  stockholder  has  advised  that it has not entered into any agreements,
understandings or arrangements with any underwriters or broker-dealers regarding
the sale of the shares. There is no underwriter or coordinating broker acting in
connection  with  the  proposed  sale  of  shares  by  the  selling stockholder.

     The  shares  will  be  sold  only through registered or licensed brokers or
dealers if required under applicable state securities laws. In addition, in some
states  the shares may not be sold unless they have been registered or qualified
for  sale  in  the  applicable  state  or  an exemption from the registration or
qualification  requirement  is  available  and  is  complied  with.

     Under  applicable  rules and regulations under the Exchange Act, any person
engaged  in  the  distribution  of  the  shares may not simultaneously engage in
market  making  activities  with respect to our common stock for a period of two
business  days  prior  to the commencement of the distribution. In addition, the
selling stockholder will be subject to applicable provisions of the Exchange Act
and  the  associated  rules  and  regulations  under the Exchange Act, including
Regulation  M,  which  provisions may limit the timing of purchases and sales of
shares  of  our  common stock by the selling stockholder. We will make copies of
this  prospectus  available  to  the  selling  stockholder and have informed the
selling  stockholder  of  the  need  to  deliver  copies  of  this prospectus to
purchasers  at  or  prior  to  the  time  of  any  sale  of  the  shares.

     We  will  bear  all  costs,  expenses  and  fees  in  connection  with  the
registration of the shares. The selling stockholder will pay all commissions and
discounts,  if  any,  attributable  to  the  sales  of  the  shares. The selling
stockholder  may agree to indemnify any broker-dealer or agent that participates
in  transactions  involving  sales  of  the shares against specific liabilities,
including  liabilities  arising  under  the  Securities  Act.  We have agreed to
indemnify  the  selling  stockholder  against specific liabilities in connection
with  the  offering  of  the  shares,  including  liabilities  arising under the
Securities  Act.

     We have agreed to maintain the effectiveness of this registration statement
until  the  earlier of such time as all the shares have been sold by the selling
stockholder  or  such  time  as  all  of the shares may be sold pursuant to Rule
144(k)  under  the Securities Act. The selling stockholder may sell all, some or
none  of  the  shares  offered  by  this  prospectus.


                                  LEGAL MATTERS

     The  validity  of  the shares of common stock offered hereby will be passed
upon  by  Cooley  Godward  LLP,  Palo  Alto,  California.

                                     EXPERTS
     The  consolidated  financial  statements incorporated in this prospectus by
reference  to  the  Annual  Report  on Form 10-K for the year ended December 31,
2000,  have  been  so  incorporated  in  reliance  on  the  report  of
PricewaterhouseCoopers  LLP,  independent accountants, given on the authority of
said  firm  as  experts  in  auditing  and  accounting.

               WHERE YOU CAN FIND MORE INFORMATION ABOUT EXELIXIS

     You  should  rely  only  on  the  information  provided  or incorporated by
reference  in  this  prospectus.  We  have authorized no one to provide you with
different  information.  We  are  not making an offer of these securities in any
state  where  the  offer  is  not  permitted.  You  should  not  assume that the
information  in  this  prospectus or any prospectus supplement is accurate as of
any  date  other  than  the  date  on  the  front  of  the  document.

     We  have  filed with the SEC a resale registration statement on Form S-3 to
register  the  common stock offered by this prospectus. However, this prospectus
does  not contain all of the information contained in the registration statement
and  the  exhibits  and  schedules  to  the  registration statement. We strongly
encourage  you to carefully read the registration statement and the exhibits and
schedules  to  the  registration  statement.

     We  file  annual, quarterly and special reports, proxy statements and other
information  with  the  SEC.  You  may read and copy any document we file at the
SEC's  Public  Reference Room at 450 Fifth Street, N.W., Washington, DC 20549 or
at  the  SEC's  other  public  reference rooms located in New York, New York and
Chicago,  Illinois.  You can request copies of these documents by contacting the
SEC  and  paying  a  fee for the copying cost. Please call the SEC at 1-800-SEC-
0330  for further information on the public reference rooms. Our SEC filings are
also  available to the public from the SEC's website at www.sec.gov.
                                                        -----------

     The  SEC  allows us to "incorporate by reference" the information contained
in  documents that we file with them, which means that we can disclose important
information to you by referring to those documents. The information incorporated
by  reference  is  considered to be part of this prospectus. Information in this
prospectus  supersedes  information incorporated by reference that we filed with
the  SEC  prior  to  the date of this prospectus, while information that we file
later  with the SEC will automatically update and supersede this information. We
incorporate  by  reference  the documents listed below and any future filings we
will  make  with  the  SEC  under  Sections  13(a),  13(c),  14  or 15(d) of the
Securities  Exchange  Act  of  1934.

     The following documents filed with the SEC are incorporated by reference in
this  prospectus:
     1.  Our  Annual  Report  on Form 10-K for the year ended December 31, 2000;
     2.  Our Quarterly Report on Form 10-Q for the quarter ended March 31, 2001;
     3.  Our  Quarterly Report on Form 10-Q for the quarter ended June 30, 2001;
     4.  Our Current Reports on Form 8-K, filed on May 15, 2001 pursuant to Item
         2 of such report, and filed on July 18, 2001 and July 26, 2001 pursuant
         to Item  5 of such report; and
     5.  The  description  of  our  common  stock  set forth in our registration
         statement  on  Form  8-A,  filed  with  the  SEC  on  April  6,  2000.

     We  will  furnish without charge to you, on written or oral request, a copy
of  any or all of the documents incorporated by reference, including exhibits to
these documents. You should direct any requests for documents to Exelixis, Inc.,
Attention:  Investor  Relations,  170  Harbor  Way,  P.O.  Box  511,  South  San
Francisco,  California  94083,  telephone:  (650)  837-7000.

     WE  HAVE NOT AUTHORIZED ANY DEALER, SALESPERSON OR OTHER PERSON TO GIVE ANY
INFORMATION  OR  REPRESENT ANYTHING NOT CONTAINED IN THIS PROSPECTUS. YOU SHOULD
RELY  ONLY  ON  THE  INFORMATION  PROVIDED  OR INCORPORATED BY REFERENCE IN THIS
PROSPECTUS. YOU SHOULD NOT RELY ON ANY UNAUTHORIZED INFORMATION. THIS PROSPECTUS
DOES  NOT  OFFER  TO  SELL  OR BUY ANY SHARES IN ANY JURISDICTION IN WHICH IT IS
UNLAWFUL.  THE  INFORMATION  IN THIS PROSPECTUS IS CURRENT AS OF THE DATE ON THE
COVER.


                                 600,600 SHARES
                                 EXELIXIS, INC.
                                  COMMON STOCK


                        _________________________________
                        ---------------------------------

                                   PROSPECTUS

                        _________________________________



                               ________ ___, 2001



                                     PART II

                   INFORMATION NOT REQUIRED IN THE PROSPECTUS

ITEM  14.  OTHER  EXPENSES  OF  ISSUANCE  AND  DISTRIBUTION

All  of  the  amounts  shown  are  estimates  except  the  SEC registration fee.

     SEC  registration  fee             $  2,347
     Legal  fees  and  expenses           75,000
     Accounting  fees  and  expenses      10,000
     Miscellaneous  expenses              27,653
                                        ________
     Total                              $115,000
                                         =======

ITEM  15.  INDEMNIFICATION  OF  DIRECTORS  AND  OFFICERS

     Under  Section  145  of  the Delaware General Corporation Law, Exelixis has
broad  powers  to  indemnify its directors and officers against liabilities they
may  incur  in  such capacities, including liabilities under the Securities Act.
Exelixis'  bylaws  also  provide  that Exelixis will indemnify its directors and
executive  officers  and  may  indemnify its other officers, employees and other
agents  to  the  fullest  extent  permitted  by  Delaware  law.

     As permitted by Delaware law, Exelixis' amended and restated certificate of
incorporation provides that no director of Exelixis will be personally liable to
Exelixis  or  its stockholders for monetary damages for breach of fiduciary duty
as  a  director,  except  for  liability:
     -  for  any  breach  of duty of loyalty to Exelixis or to its stockholders;
     -  for  acts  or  omissions  not  in good faith or that involve intentional
        misconduct  or  a  knowing  violation  of  law;
     -  for  unlawful  payment  of  dividends  or  unlawful stock repurchases or
        redemptions under Section 174 of the Delaware General Corporation Law;
        or
     -  for any transaction from which the director derived an improper personal
        benefit.

     Exelixis'  amended  and  restated  certificate  of  incorporation  further
provides  that  Exelixis must indemnify its directors and executive officers and
may  indemnify  its  other  officers, employees and agents to the fullest extent
permitted  by  Delaware  law.  Exelixis  believes that indemnification under its
amended  and  restated  certificate of incorporation covers negligence and gross
negligence  on  the  part  of  indemnified  parties.

Exelixis  has entered into indemnification agreements with each of its directors
and  certain officers. These agreements, among other things, require Exelixis to
indemnify  each  director  and officer for certain expenses including attorneys'
fees, judgments, fines and settlement amounts incurred by any such person in any
action  or  proceeding,  including  any  action  by or in the right of Exelixis,
arising  out  of the person's services as a director or officer to Exelixis, any
subsidiary  of  Exelixis  or  to  any  other company or enterprise for which the
person  provides  services  at  Exelixis'  request.

At present, there is no pending litigation or proceeding involving a director or
officer  of Exelixis as to which indemnification is being sought nor is Exelixis
aware of any threatened litigation that may result in claims for indemnification
by  any  officer  or  director.


ITEM  16.  EXHIBITS.

EXHIBIT
NUMBER      DESCRIPTION
-------     -----------

4.1         Amended  and  Restated  Certificate  of  Incorporation  (1)
4.2         Restated  Bylaws  (1)
4.3         Specimen  Stock  Certificate  (1)
5.1         Opinion  of  Cooley  Godward  LLP
10.29       Form of Stock Purchase Agreement, dated as of July 17, 2001, by and
            between Exelixis,  Inc.  and  Bristol-Myers  Squibb  Company
23.1        Consent  of  Independent  Accountants
23.2        Consent  of  Cooley  Godward  LLP  (included  in  Exhibit  5.1)
24.1        Power  of  Attorney  (included  on  signature  page)
___________________
(1)     Incorporated  by  reference  to Exelixis' Registration Statement on Form
S-1,  as amended (File No. 333-96335), originally filed with the SEC on February
7,  2000.

ITEM  17.  UNDERTAKINGS.

The  undersigned  registrant  hereby  undertakes:

     (1)  To  file, during any period in which offers or sales are being made, a
post-effective  amendment to this registration statement to include any material
information with respect to the plan of distribution not previously disclosed in
the  registration  statement  or  any material change to such information in the
registration  statement.

     (2) That, for the purpose of determining any liability under the Securities
Act,  each  post-effective  amendment  shall  be deemed to be a new registration
statement  relating  to  the  securities  it  offers,  and  the  offering of the
securities  at  that  time  shall be deemed to be the initial bona fide offering
thereof.

     (3)  To remove from registration by means of a post-effective amendment any
of the securities being registered that remain unsold at the termination of this
offering.

     (4)  That,  for  purposes of determining any liability under the Securities
Act,  each filing of the registrant's annual report pursuant to Section 13(a) or
Section  15(d)  of  the  Exchange  Act  that is incorporated by reference in the
registration  statement  shall  be  deemed  to  be  a new registration statement
relating  to  the securities offered therein, and the offering of the securities
at  that  time  shall  be  deemed  to be the initial bona fide offering thereof.

     Insofar as indemnification for liabilities arising under the Securities Act
may  be  permitted  to  directors,  officers  and  controlling  persons  of  the
registrant  pursuant  to  the foregoing provisions, or otherwise, the registrant
has  been advised that in the opinion of the SEC this form of indemnification is
against  public  policy  as  expressed  in the Securities Act and is, therefore,
unenforceable.  In  the  event  that  a  claim for indemnification against these
liabilities  (other  than  the payment by the registrant of expenses incurred or
paid  by  a  director,  officer  or  controlling person of the registrant in the
successful defense of any action, suit or proceeding) is asserted by a director,
officer  or  controlling  person  in  connection  with  the  securities  being
registered, the registrant will, unless in the opinion of its counsel the matter
has  been  settled  by  controlling  precedent, submit to a court of appropriate
jurisdiction  the  question whether such indemnification by it is against public
policy  as  expressed  in  the  Securities Act and will be governed by the final
adjudication  of  this  issue.


                                   SIGNATURES

     Pursuant  to the requirements of the Securities Act of 1933, Exelixis, Inc.
certifies  that  it  has  reasonable grounds to believe that it meets all of the
requirements  for  filing  on  Form  S-3  and  has duly caused this Registration
Statement  to  be  signed  on  its  behalf  by  the  undersigned, thereunto duly
authorized,  in  the city of South San Francisco, State of California, on August
27,  2001.
                                 EXELIXIS,  INC.

                                 By:  /s/ George A. Scangos
                                     --------------------------------------
                                     George  A.  Scangos, Ph.D.
                                     President  and  Chief  Executive  Officer

                                POWER OF ATTORNEY

    KNOW  ALL  PERSONS  BY  THESE  PRESENTS,  that  each person whose signature
appears  below  constitutes  and appoints GEORGE A. SCANGOS and GLEN Y. SATO and
each  or  any  one of them, his true and lawful attorney-in-fact and agent, with
full  power  of  substitution and resubstitution, for him and in his name, place
and  stead, in any and all capacities, to sign any and all amendments (including
post-effective  amendments  and  registration  statements filed pursuant to Rule
462)  to  this  Registration  Statement, and to file the same, with all exhibits
thereto,  and  other  documents in connection therewith, with the Securities and
Exchange  Commission,  granting unto said attorneys-in-fact and agents, and each
of them, full power and authority to do and perform each and every act and thing
requisite  and  necessary  to  be  done in connection therewith, as fully to all
intents  and  purposes  as  he might or could do in person, hereby ratifying and
confirming  all that said attorneys-in-fact and agents, or any of them, or their
or  his substitutes or substitute, may lawfully do or cause to be done by virtue
hereof.

     Pursuant  to  the  requirements  of  the  Securities  Act  of  1933,  this
Registration  Statement  has  been  signed below by the following persons in the
capacities  and  on  the  dates  indicated.

     SIGNATURE                            TITLE                      DATE

/s/ George A. Scangos       President, Chief Executive Officer  August 27, 2001
--------------------------              and Director
George A. Scangos,Ph.D.        (Principal Executive Officer)

/s/ Glen Y. Sato                 Chief Financial  Officer       August 27, 2001
-------------------------- (Principal Financial and Accounting
Glen Y. Sato                            Officer)

/s/Stelios Papadopoulos     Chairman of the Board of Directors  August 27, 2001
--------------------------
Stelios Papadopoulos, Ph.D.

--------------------------               Director
Charles Cohen, Ph.D.

--------------------------               Director
Jurgen Drews, M.D.

/s/ Geoffrey Duyk                        Director               August 27, 2001
--------------------------
Geoffrey Duyk, M.D., Ph.D.

/s/ Jason S. Fisherman                   Director               August 27, 2001
--------------------------
Jason S. Fisherman, M.D.

/s/ Jean-Francois Formela                Director               August 27, 2001
--------------------------
Jean-Francois Formela, M.D.

/s/ Vincent T. Marchesi                  Director               August 27, 2001
--------------------------
Vincent T. Marchesi,
M.D., Ph.D.

/s/ Peter Stadler                        Director               August 27, 2001
--------------------------
Peter Stadler, Ph.D.

--------------------------               Director
Lance Willsey, M.D.


                                INDEX TO EXHIBITS
                                 EXHIBIT NUMBER
                                        -------
EXHIBIT
NUMBER    DESCRIPTION
-------   -----------
4.1       Amended  and  Restated  Certificate  of  Incorporation  (1)
4.2       Restated  Bylaws  (1)
4.3       Specimen  Stock  Certificate  (1)
5.1       Opinion  of  Cooley  Godward  LLP
10.29     Form of Stock Purchase Agreement, dated as of July 17, 2001, by and
          between Exelixis, Inc.  and  Bristol-Myers  Squibb  Company
23.1      Consent  of  Independent  Accountants
23.2      Consent  of  Cooley  Godward  LLP  (included  in  Exhibit  5.1)
24.1      Power  of  Attorney  (included  on  signature  page)
___________________
(1) Incorporated by reference to Exelixis' Registration Statement on Form
    S-1,  as amended (File No. 333-96335), originally filed with the SEC on
    February 7,  2000.