X0203 3 2010-08-02 0 0001356857 Trius Therapeutics Inc TSRX 0001202793 POWELL MICHAEL C/O TRIUS THERAPEUTICS, INC. 6310 NANCY RIDGE DRIVE, SUITE 101 SAN DIEGO CA 92121 1 0 1 0 Stock Option (right to buy) 1.29 2019-02-09 Common Stock 9302 D Series A-2 Preferred Stock Common Stock 10909092 I See Footnote. Series B Preferred Stock Common Stock 5363636 I See Footnote. In accordance with its terms, the option is immediately exercisable in full; however, the shares underlying the option are subject to vesting. As of the date of this Form 3, 7,751 shares are fully vested, with the remaining 1,551 shares vesting monthly through March 1, 2011. Any shares issued upon exercise of unvested options are subject to a repurchase right in favor of the Issuer if Dr. Powell does not satisfy the option's vesting requirements. The Series A-2 Preferred Stock has no expiration date and is convertible at any time at the option of the holder and will convert upon the closing of the Issuer's initial public offering at a conversion ratio of 1 share of Common Stock for every 8.6 shares of Series A-2 Preferred Stock, for no additional consideration. See attached Exhibit 99.1. The Series B Preferred Stock has no expiration date and is convertible at any time at the option of the holder and will convert upon the closing of the Issuer's initial public offering at a conversion ratio of 1 share of Common Stock for every 8.6 shares of Series B Preferred Stock, for no additional consideration. See attached Exhibit 99.1. /s/ Michael Powell 2010-08-02