X0202 4 2006-03-28 0 0001018710 INTROGEN THERAPEUTICS INC INGN 0001356774 Aventis Inc. 3711 KENNETT PIKE, SUITE 200 GREENVILLE DE 19807 0 0 0 1 10% owner and beneficial owner 0001267075 AVENTIS HOLDINGS INC 3711 KENNETT PIKE SUITE 200 GREENVILLE DE 19807 0 0 0 1 10% owner and beneficial owner Common 2006-03-28 4 S 0 9526 5.31 D 4178884 I SFN For reporting person Aventis Holdings Inc., reflects ownership of (i) 1,835,163 shares of common stock owned directly by Aventis Holdings Inc., and (ii) 2,343,721 shares of common stock owned by its subsidiary Aventis Pharmaceuticals Inc. For reporting person Aventis Inc., reflects ownership of shares owned directly by Aventis Holdings Inc. and Aventis Pharmaceuticals Inc. Kathleen A. Winter 2006-03-30 Kathleen A. Winter 2006-03-30