EXHIBIT 12.1 CONNETICS CORPORATION STATEMENT OF COMPUTATION OF RATIOS OF EARNINGS TO FIXED CHARGES For the year ended December 31, Three months ended Nine months ended ----------------------------------------------------------- (in thousands) September 30, 2003 September 30, 2003 2002 2001 2000 1999 1998 ------------------ ------------------ --------- --------- -------- --------- -------- Income (loss) from continuing operations before income taxes $ 1,629 $ (4,330) $ (16,409) $ (16,397) $ 33,198 $ (27,283) $(26,595) Add fixed charges 841 1,384 658 460 597 1,099 1,424 ---------- ---------- --------- --------- -------- --------- -------- Earnings (as defined) $ 2,470 $ (2,946) $ (15,751) $ (15,937) $ 33,795 $ (26,184) $(25,171) ========== ========== ========= ========= ======== ========= ======== Fixed Charges Interest Expense 517 692 11 46 235 868 1,304 Amortization of debt issuance costs 182 238 0 0 0 0 0 Estimated interest component of rent expenses 142 454 647 414 362 231 120 ---------- ---------- --------- --------- -------- --------- -------- Total fixed charges 841 1,384 658 460 597 1,099 1,424 ========== ========== ========= ========= ======== ========= ======== Ratio of earnings to fixed charges 2.9 Note(ii) Note(i) Note(i) 56.6 Note(i) Note(i) ---------- ---------- --------- --------- -------- --------- -------- (i) Earnings, as defined, were insufficient to cover fixed charges by $16.4 million, $16.4 million, $27.3 million, and $26.6 million in the fiscal years 2002, 2001, 1999, and 1998, respectively. (ii) Earnings, as defined, were insufficient to cover fixed charges by $4.3 million in the nine months ended September 30, 2003.