Cadence Pharmaceuticals, Inc announced positive topline results from Study 304, a phase-III clinical trial of Acetavance, the company's intravenous formulation of acetaminophen, for the treatment of acute pain following abdominal laparoscopic surgery. Study 304 successfully met its primary endpoint of a statistically significant reduction in summed pain intensity differences from baseline over 24 hours (SPID24) for Acetavance 1000 mg compared to placebo (p < 0.01).

Study 304 was a randomized, double-blind, multi-centre study of 244 patients designed to evaluate the safety and efficacy of two dosing regimens of Acetavance, 1000 mg every six hours and 650 mg every four hours, compared to placebo over 24 hours. In addition to the 1000 mg dose administered every six hours meeting the primary endpoint, the trial also achieved a statistically significant reduction in SPID24 for the 650mg dose administered every four hours (p = 0.02). Consistent with other placebo-controlled clinical trials with intravenous acetaminophen, reported safety events from the Acetavance and placebo treated patients were similar. The company plans to communicate the full study results in a peer-reviewed venue.

Cadence also announced today that Study 351, a clinical trial evaluating the safety of repeated doses of Acetavance in adults, demonstrated a hepatic and general safety profile of Acetavance comparable to control (standard of care), with numerically lower proportions of subjects with elevated liver function tests in the two Acetavance groups compared to the standard of care group. Study 351 was an open-label, multi-centre study of 213 hospitalized patients randomized to receive repeated doses of Acetavance 1000mg every six hours, Acetavance 650mg every four hours, or standard of care for up to five days.

The adult clinical development program for Acetavance is now complete. An analysis of data from nine placebo-controlled, single and repeated dose trials conducted in more than 1,300 adults with acute postoperative pain or fever demonstrated that intravenous acetaminophen has a hepatic safety profile comparable to placebo, with liver function test elevations reported as a treatment-emergent adverse event in 5.0 per cent of subjects who received placebo compared to only 3.1 per cent of subjects who received intravenous acetaminophen.

In addition, the company announced today that Study 102, a clinical trial to evaluate the pharmacokinetics of Acetavance in 75 paediatric patients, demonstrated the expected pharmacokinetic profile, generally comparable to adults, with an age-related reduction in clearance in newborns. Acetavance was well-tolerated across all age groups, ranging from newborns to adolescents. Furthermore, the company announced that it has closed patient enrolment in its last required clinical trial of Acetavance, Study 352, evaluating safety in children after one to five days of repeated doses of Acetavance up to 15 mg/kg. With the results of Study 352, which are expected in the first quarter of 2009, the planned paediatric clinical development program for Acetavance will also be complete.

"We are pleased with the successful completion of studies 304, 351, and 102," stated Ted Schroeder, president and chief executive officer of Cadence. "The Acetavance New Drug Application for the treatment of acute pain and fever in both adults and children remains on track for submission during the second quarter of 2009."

Cadence Pharmaceuticals is a biopharmaceutical company focused on in-licensing, developing and commercializing proprietary product candidates principally for use in the hospital setting.