Study to Evaluate the Efficacy, Safety and Tolerability of N1539

Inclusion Criteria: * moderate to severe pain with VAS of \>/= 45 mm * undergo open abdominal hysterectomy * ASA I or II * signed ICF * BMI \>18.5 and \< 31.5 kg/m\^2 Exclusion Criteria: * suspected metastatic cervical or endometrial cancer * prior abdominal surgery with postoperative complications * active pancreatitis, obstruction of biliary tree or total bilirubin\> 2.5 mg/dL * active GI bleeding, or peptic ulcer disease * unstable medical condition * HbA1c \>9.5 or uncontrolled diabetes * SBP \>150 mmHg or DBP \> 95 mmHg * personal or familial contraindication to undergoing general anesthesia * Antihypertensive agents or diabetic regimen that is not stable (4 weeks prior to surgery) * taking CNS agents for pain * acetaminophen or NSAIDs not discontinued for at least 5 half-lives prior to planned surgery * currently taking an opioid or has taken an opioid chronically for pain in past 2 years * corticosteroid or systemic corticosteroids within 6 weeks of planned surgery * has a known bleeding disorder or taking agents affecting coagulation * history of intolerance or allergic reactions to NSAIDs, COX-2 inhibitors, aspirin and other salicylates * receiving lithium or a combination of furosemide with an ACE inhibitor or angiotensin receptor blocker * Known to have sleep apnea * History of hepatitis B or C * AST or ALT \> 2 times the upper limit of normal * Known or suspected COPD with retention of carbon dioxide * psychiatric condition that impairs the capability of the subject to report pain