Mail Stop 6010 August 9, 2005 Mr. James W. Albrecht, Jr. Chief Financial Officer Introgen Therapeutics, Inc. 301 Congress Avenue, Suite 1850 Austin, TX 78701 Re:	Introgen Therapeutics, Inc. 		Form 10-K for the fiscal year ended December 31, 2004 		Form 10-Q for the quarter ended March 31, 2005 	File No. 000-21291 Dear Mr. Albrecht: We have limited our review of your filing to the issue we have addressed in our comment. Where indicated, we think you should revise your document in response to this comment. If you disagree, we will consider your explanation as to why our comment is inapplicable or a revision is unnecessary. Please be as detailed as necessary in your explanation. 	Please understand that the purpose of our review process is to assist you in your compliance with the applicable disclosure requirements and to enhance the overall disclosure in your filing. We look forward to working with you in these respects. We welcome any questions you may have about our comment or on any other aspect of our review. Feel free to call us at the telephone numbers listed at the end of this letter. Management`s Discussion and Analysis of Financial Condition and Results of Operations, page 30 1. We acknowledge your table included in the section entitled "Product Development Programs" on page 9. However, we believe that your disclosures about historical research and development expenses and estimated future expenses related to your major research and development projects could be enhanced for investors. Please refer to the Division of Corporation Finance "Current Issues and Rulemaking Projects Quarterly Update" under section VIII - Industry Specific Issues - Accounting and Disclosure by Companies Engaged in Research and Development Activities. You can find it at the following website address: http://www.sec.gov/divisions/corpfin/cfcrq032001.htm#secviii. Please disclose the following information for each of your major research and development projects: a. The costs incurred during each period presented and to date on the project; b. The nature, timing and estimated costs of the efforts necessary to complete the project; c. The anticipated completion date; d. The risks and uncertainties associated with completing development on schedule and the consequences to your operations, financial position and liquidity if the project is not completed timely; and, finally e. The period in which material net cash inflows from your significant projects are expected to commence. Regarding a., if you do not maintain research and development costs by project, please disclose why management does not maintain and evaluate research and development costs by project. Include other quantitative or qualitative analyses that indicate the amount of the company`s resources being used on these projects. Regarding b. and c., please disclose the amount or range of estimated costs and timing to complete the phase in process and each future phase. To the extent that information is not estimable, please disclose the facts and circumstances indicating the uncertainties that preclude you from making a reasonable estimate. * * * * Please amend your filing and subsequent Form 10-Q for the quarter ended March 31, 2005 within 10 business days or tell us when you will provide us with a response. You may wish to provide us with marked copies of the amendment to expedite our review. Please furnish a cover letter with your amendment that keys your responses to our comment and provides any requested information. Detailed cover letters greatly facilitate our review. Please file your letter on EDGAR under the form type label CORRSEP. Please understand that we may have additional comments after reviewing your amendment. 	We urge all persons who are responsible for the accuracy and adequacy of the disclosure in the filing to be certain that they have provided all information required under the Securities Exchange Act of 1934 and that they have provided all information investors require for an informed investment decision. Since the company and its management are in possession of all facts relating to a company`s disclosure, they are responsible for the accuracy and adequacy of the disclosures they have made. 	In connection with responding to our comments, please provide, in your letter, a statement from the company acknowledging that: * the company is responsible for the adequacy and accuracy of the disclosure in the filing; * staff comments or changes to disclosure in response to staff comments do not foreclose the Commission from taking any action with respect to the filing; and * the company may not assert staff comments as a defense in any proceeding initiated by the Commission or any person under the federal securities laws of the United States. In addition, please be advised that the Division of Enforcement has access to all information you provide to the staff of the Division of Corporation Finance in our review of your filing or in response to our comments on your filing. You may contact Amy Bruckner, Staff Accountant, at (202) 551- 3657 or Joel Parker, Accounting Branch Chief, at (202) 551-3651 if you have questions regarding comments on the financial statements and related matters. Please contact me at (202) 551-3679 with any other questions. Sincerely, 							Jim B. Rosenberg 							Senior Assistant Chief Accountant ?? ?? ?? ?? James W. Albrecht, Jr. Introgen Therapeutics, Inc. August 9, 2005 Page 3