X0202 3 2007-08-08 0 0001108205 CURIS INC CRIS 0001346824 RA CAPITAL MANAGEMENT, LLC 111 HUNTINGTON AVENUE, SUITE 610 BOSTON MA 02199 0 0 1 0 0001185039 ALDRICH RICHARD C/O RA CAPITAL MANAGEMENT, LLC 111 HUNTINGTON AVENUE, SUITE 610 BOSTON MA 02199 0 0 1 0 0001384859 Kolchinsky Peter C/O RA CAPITAL MANAGEMENT, LLC 111 HUNTINGTON AVENUE, SUITE 610 BOSTON MA 02199 0 0 1 0 0001392402 RA Capital Biotech Fund II, L.P. C/O RA CAPITAL MANAGEMENT, LLC 111 HUNTINGTON AVENUE, SUITE 610 BOSTON MA 02199 0 0 1 0 0001315082 RA Capital Biotech Fund LP C/O RA CAPITAL MANAGEMENT, LLC 111 HUNTINGTON AVENUE, SUITE 610 BOSTON MA 02199 0 0 1 0 Common Stock 7520564 I See Footnote Warrants to Purchase Common Stock 1.02 2012-08-08 Common Stock 2632198 I See Footnote These shares represent 7,388,202 shares held by RA Capital Biotech Fund, L.P. ("Fund I"), and 132,362 shares held by RA Capital Biotech Fund II, L.P. ("Fund II"). RA Capital Management, LLC (the "General Partner") is the general partner of each of Fund I and Fund II, and Richard H. Aldrich and Peter Kolchinsky are the sole managers of RA Capital Management, LLC. Each of the Reporting Persons disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein, if any. These warrants are exerciseable for cash, provided, however, that the warrants are not exerciseable to the extent the holder of any such warrant, together with any affiliates, holds or beneficially owns more than 9.99% of the outstanding Common Stock of the issuer, unless such restriction is waived by the holder upon not less than 61 days written notice to the issuer. These warrants represent the right for RA Capital Biotech Fund, L.P. ("Fund I") to acquire 2,585,871 additional shares of Common Stock and for RA Capital Biotech Fund II, L.P. ("Fund II") to acquire 46,327 additional shares of Common Stock, in each case upon the terms and conditions set forth in such warrant. RA Capital Management, LLC (the "General Partner") is the general partner of each of Fund I and Fund II, and Richard H. Aldrich and Peter Kolchinsky are the sole managers of RA Capital Management, LLC. Each of the Reporting Persons disclaims beneficial ownership of such shares except to the extent of his or its pecuniary interest therein, if any. /s/ Peter Kolchinsky Manager of RA Capital Management LLC, 2007-08-14 /s/ Richard H. Aldrich 2007-08-14 /s/ Peter Kolchinsky 2007-08-14 /s/ Peter Kolchinsky 2007-08-14 /s/ Peter Kolchinsky 2007-08-14