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<TYPE>8-K
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<ITEMS>9
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<CONFORMED-NAME>LEXICON GENETICS INC/TX
<CIK>0001062822
<ASSIGNED-SIC>2835
<IRS-NUMBER>760474169
<FISCAL-YEAR-END>1231
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<FORM-TYPE>8-K
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<FILE-NUMBER>000-30111
<FILM-NUMBER>03674875
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<BUSINESS-ADDRESS>
<STREET1>4000 RESEARCH FOREST DRIVE
<STREET2>281-364-0100
<CITY>THE WOODLANDS
<STATE>TX
<ZIP>77381
<PHONE>2813640100
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<STREET1>4000 RESEARCH FOREST DR
<CITY>THE WOODLANDS
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<TYPE>8-K
<SEQUENCE>1
<FILENAME>h05343e8vk.txt
<DESCRIPTION>LEXICON GENETICS INCORPORATED - DATED 5/1/03
<TEXT>
<PAGE>
================================================================================


                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549



                                    FORM 8-K


                                 CURRENT REPORT
     PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934



          DATE OF REPORT (DATE OF EARLIEST EVENT REPORTED): MAY 1, 2003


                          LEXICON GENETICS INCORPORATED
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)



<TABLE>
<S>                                   <C>                            <C>
           DELAWARE                          000-30111                     76-0474169
(STATE OR OTHER JURISDICTION OF       (COMMISSION FILE NUMBER)          (I.R.S. EMPLOYER
 INCORPORATION OR ORGANIZATION)                                      IDENTIFICATION NUMBER)
</TABLE>


                          8800 TECHNOLOGY FOREST PLACE
                           THE WOODLANDS, TEXAS 77381
                         (ADDRESS OF PRINCIPAL EXECUTIVE
                              OFFICES AND ZIP CODE)


                                 (281) 863-3000
                         (REGISTRANT'S TELEPHONE NUMBER,
                              INCLUDING AREA CODE)


================================================================================
<PAGE>
ITEM 7.  FINANCIAL STATEMENTS AND EXHIBITS

         (c)  Exhibits


  EXHIBIT NO.                         DESCRIPTION
  -----------                         -----------
      99.1        --   Press Release of Lexicon Genetics Incorporated dated
                       May 1, 2003


ITEM 9.  REGULATION FD DISCLOSURE

         The following information is furnished pursuant to Item 12, "Disclosure
of Results of Operations and Financial Condition."

         On May 1, 2003, we issued a press release to report our financial
results for the quarter ended March 31, 2003. A copy of the press release is
attached to this current report on Form 8-K as Exhibit 99.1.

         In accordance with the procedural guidance in SEC Release No. 33-8216,
the information in this Form 8-K and the Exhibit attached to this Form 8-K are
being furnished under "Item 9. Regulation FD Disclosure" rather than under "Item
12. Disclosure of Results of Operations and Financial Condition." The
information shall not be deemed "filed" for purposes of Section 18 of the
Securities Exchange Act of 1934 (the "Exchange Act") or otherwise subject to the
liabilities of that section, nor shall it be deemed incorporated by reference in
any filing under the Securities Act of 1933 or the Exchange Act, except as
expressly set forth by specific reference in such a filing.


                                       2
<PAGE>
                                   SIGNATURES

         Pursuant to the requirements of the Securities Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                             LEXICON GENETICS INCORPORATED


Date: May 1, 2003                            By: /s/ JEFFREY L. WADE
                                                 -------------------------------
                                                 Jeffrey L. Wade
                                                 Executive Vice President and
                                                 General Counsel


                                       3
<PAGE>
                                INDEX TO EXHIBITS


<Table>
<Caption>
  EXHIBIT NO.                       DESCRIPTION
  -----------                       -----------
  <S>             <C>
      99.1        --   Press Release of Lexicon Genetics Incorporated dated May 1, 2003
</Table>


</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-99.1
<SEQUENCE>3
<FILENAME>h05343exv99w1.txt
<DESCRIPTION>PRESS RELEASE DATED MAY 1, 2003
<TEXT>
<PAGE>
                                                                    EXHIBIT 99.1


                            LEXICON GENETICS REPORTS
                      2003 FIRST QUARTER FINANCIAL RESULTS


THE WOODLANDS, TEXAS, MAY 1, 2003 - Lexicon Genetics Incorporated (Nasdaq:
LEXG), a biopharmaceutical company focused on the discovery of breakthrough
treatments for human disease, today reported financial results for the three
months ended March 31, 2003.

REVENUES: Lexicon's revenues for the three months ended March 31, 2003 increased
six percent to $8.1 million from $7.7 million for the corresponding period of
2002. Revenues for the three months ended March 31, 2003 included:

      o     subscription and license fees of $3.1 million, consisting primarily
            of access fees from the Company's LexVision(R) collaborations and
            technology license fees from sublicenses of the Company's gene
            targeting technology; and

      o     collaborative research revenues of $5.0 million, consisting
            primarily of revenues from Lexicon's therapeutic protein
            collaborations and revenues from functional genomics collaborations
            with pharmaceutical and biotechnology companies.

RESEARCH AND DEVELOPMENT EXPENSES: Research and development expenses for the
three months ended March 31, 2003 increased 18 percent to $19.8 million from
$16.9 million for the corresponding period of 2002. The increase primarily
reflects the completion of the scale-up of Lexicon's gene knockout and
functional analysis programs and continued expansion of the Company's drug
discovery programs and medicinal chemistry operations. With Lexicon's
infrastructure in place, the Company does not see any material expansion in
personnel required for the near term. Research and development expenses for the
three months ended March 31, 2003 and 2002 each included $1.3 million of
non-cash, stock-based compensation expense primarily relating to option grants
made prior to the Company's April 2000 initial public offering.

GENERAL AND ADMINISTRATIVE EXPENSES: General and administrative expenses for the
three months ended March 31, 2003 decreased three percent to $5.8 million from
$6.0 million for the corresponding period of 2002. General and administrative
expenses for the three months ended March 31, 2003 and 2002 each included $1.3
million of non-cash, stock-based compensation expense.

INTEREST AND OTHER INCOME, NET: Interest and other income, net decreased to $0.4
million for the three months ended March 31, 2003 from $1.1 million in the
corresponding period of 2002 due to lower average cash and investment balances,
lower average interest rates, and the accrual of interest expense under the
December 2002 loan from Genentech, Inc.

NET LOSS: Net loss for the three months ended March 31, 2003 increased to $17.1
million, or $0.33 per share, from a net loss of $14.1 million, or $0.27 per
share, in the corresponding period of 2002. Excluding non-cash, stock-based
compensation charges, net loss for the three months ended March 31, 2003 was
$14.6 million, or $0.28 per share, as compared to a net loss of $11.5 million,
or $0.22 per share, for the corresponding period of 2002.

As a complement to reporting net loss and net loss per common share in
accordance with generally accepted accounting principles, or GAAP, Lexicon
provides net loss and net loss per common share results excluding non-cash,
stock-based compensation. Lexicon uses these results in establishing budgets


<PAGE>
and believes it is useful in measuring the performance of the Company's
business. A reconciliation of these results to GAAP is included in the selected
financial data set forth below.

CASH AND INVESTMENTS: As of March 31, 2003, Lexicon had approximately $107.6
million in cash and investments, including restricted cash and investments,
compared to $123.1 million as of December 31, 2002. Restricted cash and
investments were $57.7 million on both such dates.

"We had a very positive first quarter of 2003," said Arthur T. Sands, M.D.,
Ph.D., president and chief executive officer of Lexicon. "We revealed a new
discovery with potential for the treatment of osteoporosis, announced the
renewal of two of our OmniBank(R) Universal agreements, appointed the chairman
of our new Medical Advisory Board and confirmed the direct correlation between
knockout mice and the therapeutic effects of drugs in our published evaluation
of the targets of the 100 best-selling drugs."

FIRST QUARTER 2003 HIGHLIGHTS:

DISCOVERY OF A DRUG TARGET FOR THE POTENTIAL TREATMENT OF OSTEOPOROSIS: Lexicon
announced that the Company has identified and physiologically validated a novel
target for the development of drugs to treat osteoporosis. In female mice with
the target knocked out, Lexicon scientists observed a 52 percent increase in
trabecular bone mineral density within the vertebral spinal column and a 144
percent increase in trabecular bone mineral density of the leg femur bone, both
key representative fracture points in osteoporosis sufferers. Lexicon plans to
develop small molecule drugs that inhibit the enzyme target, which could
potentially increase bone density in patients that suffer from osteoporosis.

EXTENSIONS OF TWO OMNIBANK UNIVERSAL AGREEMENTS: Lexicon announced the extension
of its OmniBank Universal agreements with Boehringer Ingelheim Pharmaceuticals
Inc. and Johnson & Johnson Pharmaceutical Research & Development, L.L.C.

RETROSPECTIVE EVALUATION OF THE TARGETS OF THE 100 BEST-SELLING DRUGS: Lexicon
published in the January 2003 issue of Nature Reviews Drug Discovery a
retrospective evaluation of the targets of the 100 best-selling drugs of 2001 as
modeled by mouse knockout phenotypes. The article concluded that in most cases
there is a direct correlation between the knockout and the therapeutic effect of
the drug. The 100 best-selling drugs of 2001 modulate a total of 43 host
targets. Of these 43 targets, 34 have been knocked out in the mouse. 85% of
those knockouts were informative with respect to the physiological function and
pharmaceutical utility of the target.

APPOINTMENT OF MEDICAL ADVISORY BOARD CHAIRMAN: Lexicon appointed Alan S. Nies,
M.D. as chairman of Lexicon's Medical Advisory Board. In his new role, Dr. Nies
will assist in the development and implementation of strategies for clinical
development of potential products arising from Lexicon's drug discovery
programs. Dr. Nies brings over 40 years of clinical and pharmacological
expertise to Lexicon, having most recently served as Senior Vice President,
Clinical Sciences at Merck & Co., Inc. During his career, Dr. Nies has served on
numerous national committees and editorial boards, has received many academic
and professional honors, and has authored more than 150 publications. He holds a
B.S. degree from Stanford University and received his M.D. degree from Harvard
Medical School.

LEXICON CONFERENCE CALL:

Dr. Arthur T. Sands, president and chief executive officer, and Julia P.
Gregory, executive vice president and chief financial officer, will review
Lexicon's operating highlights and financial results for the three months ended
March 31, 2003 and will discuss the company's expectations for the second
quarter in a telephone conference call at 11:00 a.m. EDT today, May 1, 2003.


<PAGE>
The audio web cast can be heard by logging on to www.lexicon-genetics.com. It
will be archived and available for review on line through May 6, 2003.

Conference call participants may dial: 800/818-5264 (domestic USA), 913/981-4910
(international). A replay of the call will be available through May 6, 2003.
Replay numbers: 888/203-1112 (domestic), 719/457-0820 (international). Pass code
for all callers: 492554.

Lexicon Genetics is a biopharmaceutical company focused on the discovery of
breakthrough treatments for human disease. Lexicon is using gene knockout
technology to systematically discover in living mammals, or in vivo, the
physiological functions and pharmaceutical utility of genes. The Company's gene
function discoveries fuel therapeutic discovery programs in diabetes, obesity,
cardiovascular disease, immune disorders, neurological disease and cancer.
Lexicon has established drug discovery alliances and functional genomics
collaborations with leading pharmaceutical and biotechnology companies, research
institutes and academic institutions throughout the world to commercialize its
technology and turn its discoveries into drugs. Additional information about the
Company is available through Lexicon's corporate website,
www.lexicon-genetics.com.

This press release contains "forward-looking statements," including statements
about Lexicon's growth and future operating results, discovery and development
of products, strategic alliances, and intellectual property, as well as other
matters that are not historical facts or information. These forward-looking
statements are based on management's current assumptions and expectations and
involve risks, uncertainties and other important factors, specifically including
those relating to Lexicon's ability to develop drug candidates from its
discoveries, achieve its operational objectives, obtain patent protection for
its discoveries and establish strategic alliances, that may cause Lexicon's
actual results to be materially different from any future results expressed or
implied by such forward-looking statements. Information identifying such
important factors is contained under "Factors Affecting Forward-Looking
Statements" and "Business - Risk Factors" in Lexicon's annual report on Form
10-K for the year ended December 31, 2002, as filed with the Securities and
Exchange Commission. Lexicon undertakes no obligation to update or revise any
such forward-looking statements, whether as a result of new information, future
events or otherwise.

                                      # # #


CONTACT:
FOR LEXICON GENETICS:
Chas Schultz
Director, Investor Relations and
Financial Analysis
281-863-3421

<PAGE>
                          LEXICON GENETICS INCORPORATED

                             SELECTED FINANCIAL DATA


<Table>
<Caption>
CONSOLIDATED STATEMENTS OF OPERATIONS DATA                      THREE MONTHS ENDED
(In thousands, except per share data)                                MARCH 31,
                                                               --------------------
                                                                 2003        2002
                                                               --------    --------
                                                                    (UNAUDITED)
<S>                                                            <C>         <C>
Revenues:
   Subscription and license fees ...........................   $  3,102    $  3,395
   Collaborative research ..................................      4,993       4,256
   Compound libraries and other ............................         11           5
                                                               --------    --------
     Total revenues ........................................      8,106       7,656
Operating expenses:
   Research and development, including stock-based
     compensation of $1,270 and $1,307, respectively .......     19,834      16,864
   General and administrative, including stock-based
     compensation of $1,276 and $1,282, respectively .......      5,804       5,969
                                                               --------    --------
     Total operating expenses ..............................     25,638      22,833
                                                               --------    --------
Loss from operations .......................................    (17,532)    (15,177)
Interest and other income ..................................        468       1,120
Interest expense ...........................................        (81)         (2)
                                                               --------    --------
Net loss ...................................................   $(17,145)   $(14,059)
                                                               ========    ========
Adjustment for stock-based compensation (1) ................   $  2,546    $  2,589
                                                               --------    --------
Net loss, excluding stock-based compensation (1) ...........   $(14,599)   $(11,470)
                                                               ========    ========

Net loss per common share, basic and diluted ...............   $  (0.33)   $  (0.27)
                                                               ========    ========
Net loss per common share, excluding stock-based
   Compensation (1) ........................................   $  (0.28)   $  (0.22)
                                                               ========    ========
Shares used in computing net loss per common share .........     52,371      52,126
</Table>

<Table>
<Caption>
                                                                 AS OF        AS OF
CONSOLIDATED BALANCE SHEET DATA                                MARCH 31,   DECEMBER 31,
(IN THOUSANDS)                                                    2003         2002
                                                               ---------   ------------
                                                              (UNAUDITED)
<S>                                                            <C>         <C>
Cash and investments, including restricted cash and
   investments of $57,710 ..................................   $ 107,587    $ 123,096
Property and equipment, net ................................      35,516       37,362
Goodwill ...................................................      25,798       25,798
Intangible assets other than goodwill, net .................       3,940        4,240
Total assets ...............................................     181,967      201,772
Deferred revenue ...........................................      15,640       18,647
Long-term debt .............................................       4,000        4,000
Deferred stock compensation ................................      (8,507)     (11,106)
Accumulated deficit ........................................    (166,890)    (149,745)
Total stockholders' equity .................................     155,321      169,902
</Table>

(1)   In addition to reporting net loss and net loss per common share in
      accordance with generally accepted accounting principles, or GAAP, Lexicon
      provides net loss and net loss per common share excluding non-cash,
      stock-based compensation expense.

</TEXT>
</DOCUMENT>
</SUBMISSION>
