|Exhibit 99.1
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|INTROGEN THERAPEUTICS REPORTS FIRST QUARTER 2003
RESULTS
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|AUSTIN, TX, May 13, 2003 Introgen Therapeutics,
Inc. (NASDAQ: INGN) announced today that its results for the quarter ended March 31,
2003, were consistent with its expectations, during which time Introgen reported progress
in its clinical development program and intellectual property portfolio.
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|Introgen reported a net loss of $5.4 million, or $0.25 per
      share, for the quarter ended March 31, 2003. These results compare to a
      net loss of $7.9 million, or $0.37 per share, for the quarter ended March
      31, 2002. Cash used during the first quarter of 2003 was $4.4 million, which
      is $3.1 million less than the $7.5 million of cash used during the quarter
      ended December 31, 2002.
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|Introgen had revenue of $150,000  for the
quarter  ended March 31,  2003,  compared to revenue of $229,000 for the quarter  ended
March  31, 2002.  Total  operating  expenses were $5.7 million for the quarter ended
March 31, 2003,  compared to $8.5 million for the quarter  ended March 31, 2002.
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|At March 31, 2003, the Company had cash and cash
equivalents of $19.1 million.
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|Introgens  president and CEO, David G. Nance,
said,  Introgens  quarter reflects the commitment we made to reduce our cash burn,
and  the success of achieving  that goal. We are moving ahead with
registration  plans for ADVEXIN in head and neck cancer and  designing  pivotal trials
for ADVEXINs second  indication and INGN 241.We released news related to a number of
important  publications and events  this year and are looking  forward to the annual
meeting of the  American  Society of Clinical  Oncology  where we will be  presenting
ADVEXIN data including phase 2 data in breast cancer and additional INGN 241 clinical
data.
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|Quarterly Conference Call
      Introgen has scheduled a conference call to discuss the financial results
      at 4:30 p.m. ET today. Interested parties can access a live Internet broadcast
      at www.introgen.com or www.companyboardroom.com. For those unable to listen
      to the broadcast the call will be archived at Introgens Website at
      www.introgen.com in the Investor Relations section.
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|Introgen is a leader in the development and
production of gene-based drugs for the treatment of cancer and other diseases.  Introgen
maintains integrated research, development, manufacturing, clinical and regulatory
departments and operates a commercial-scale, CGMP  manufacturing facility.
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|Certain statements in this press release that
are not strictly historical may be forward-looking statements, which involve
risks  and uncertainties.  Such forward-looking statements include, but are not limited
to, those relating to Introgens future success with  its clinical development program,
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|registration plans for ADVEXIN and INGN 241, or
pivotal trial plans for ADVEXINs second  indication. There can be no assurance that
Introgen will be able to commercially develop gene-based drugs, that necessary regulatory
approvals will be obtained or that any clinical trials or studies undertaken will be
successful or that the proposed treatments will  prove to be safe and/or effective.  The
actual results may differ from those described in this press release due to risks and
uncertainties that exist in Introgens operations and business environment, including,
but without limitation, Introgens stage of  product development and the limited
experience in the development of gene-based drugs in general, Introgens dependence upon
proprietary technology and current competition, history of operating losses and
accumulated deficits, reliance on collaborative  relationships, and uncertainties related
to clinical trials, the safety and efficacy of Introgens product candidates, the ability
to  obtain the appropriate regulatory approvals, patent protection and market acceptance,
as well as other risks detailed from time to  time in Introgens filings with the
Securities and Exchange Commission, including its annual report on Form 10-K filed on
March 31,  2003 and its quarterly report on Form 10-Q filed on November 13, 2002.
Introgen undertakes no obligation to publicly release the  results of any revisions to
any forward-looking statements that reflect events or circumstances arising after the
date hereof.
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|INTROGEN THERAPEUTICS,
        INC. AND SUBSIDIARIES
      CONSOLIDATED BALANCE SHEET
|-------------------------------------------------------------------------------------
|                                                                                     
|                                                                                     
|                                                                                     
|                                                                                     
|                                                                                     
|CASH AND CASH EQUIVALENTS                                                            
|OTHER CURRENT ASSETS                                                                 
|PROPERTY AND EQUIPMENT, NET                                                          
|OTHER ASSETS                                                                         
|                                                                                     
|TOTAL ASSETS                                                                         
|                                                                                     
|ACCOUNTS PAYABLE AND OTHER CURRENT
        LIABILITIES                               
|                                                                                     
|NOTES PAYABLE AND CAPITAL LEASE
        OBLIGATIONS, NET                             
|OF CURRENT PORTION                                                                   
|OTHER LONG TERM LIABILITIES                                                          
|                                                                                     
|TOTAL LIABILITIES                                                                    
|                                                                                     
|TOTAL STOCKHOLDERS' EQUITY                                                           
|                                                                                     
|TOTAL LIABILITIES AND STOCKHOLDERS'
        EQUITY                                   
|                                                                                     

|INTROGEN THERAPEUTICS,
        INC. AND SUBSIDIARIESCONSOLIDATED STATEMENT
        OF OPERATIONS(Unaudited)
|-----------------------------------------------------------------------------------------------------------
|                                                                                                           
|                                                                                                           
|                                                                                                           
|                                                                                                           
|                                                                                                           
|CONTRACT MANUFACTURING, GRANT AND
             OTHER REVENUE                                               
|                                                                                                           
|OPERATING EXPENSES:                                                                                        
|RESEARCH
        AND DEVELOPMENT                                                                           
|GENERAL
        AND ADMINISTRATIVE                                                                         
|                                                                                                           
|TOTAL OPERATING EXPENSES                                                                                   
|                                                                                                           
|LOSS FROM OPERATIONS                                                                                       
|INTEREST INCOME, INTEREST EXPENSE
        AND                                                              
|OTHER
        INCOME, NET                                                                                  
|                                                                                                           
|NET (LOSS)                                                                                                 
|                                                                                                           
|NET LOSS PER SHARE, BASIC AND DILUTED                                                                      
|SHARES USED IN COMPUTING BASIC
        AND DILUTED                                                         
|NET LOSS PER SHARE                                                                                         
|                                                                                                           



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|Editors Note: For more information on Introgen
Therapeutics, or for a menu of archived press releases, please visit Introgens  Website
at www.introgen.com.
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