EXHIBIT 12.1 CONNETICS CORPORATION STATEMENT OF COMPUTATION OF RATIOS OF EARNINGS TO FIXED CHARGES Three Months For the year ended December 31, Ended ------------------------------------------------------------------- March 31, (in thousands) 2004 2003 2002 2001 2000 1999 ------------ -------- -------- -------- -------- -------- Income (loss) from continuing operations before income taxes $ 2,116 $ (2,933) $(16,409) $(16,397) $ 33,198 $(27,283) Add fixed charges 1,042 2,261 658 460 597 1,099 -------- -------- -------- -------- -------- -------- Earnings (as defined) $ 3,158 $ (672) $(15,751) $(15,937) $ 33,795 $(26,184) ======== ======== ======== ======== ======== ======== Fixed Charges Interest Expense 691 1,202 11 46 235 868 Amortization of debt issuance costs 184 430 0 0 0 0 Estimated interest component of rent expenses 167 629 647 414 362 231 -------- -------- -------- -------- -------- -------- Total fixed charges 1,042 2,261 658 460 597 1,099 ======== ======== ======== ======== ======== ======== Ration of earnings fixed charges 3.0 Note(i) Note(i) Note(i) 56.6 Note(i) -------- -------- -------- -------- -------- -------- (i) Earnings, as defined, were insufficient to cover fixed charges by $2.9 million, $16.4 million, $16.4 million and $27.3 million in the fiscal years 2003, 2002, 2001, and 1999, respectively.