This is a randomized, double-blind, multicenter, repeat-dose study of fixed doses of Q8003 12 mg/8 mg given q6hr compared to morphine sulfate 24 mg and oxycodone hydrochloride 16 mg given q6hr for the management of acute moderate to severe postoperative pain for 48 hours following bunionectomy surgery.

Inclusion Criteria:

• Patient is male or female and at least 18 years of age.
• Females must be non-pregnant, non-lactating, and practicing an acceptable method of birth control, or be surgically sterile or postmenopausal (amenorrhea for ≥ 12 months). Non-pregnancy will be confirmed by pregnancy tests conducted at Screening and Pre-treatment.
• Patient is scheduled for bunionectomy surgery, meets the criteria of an ASA Class I to III, and is willing to stay in the study center for at least 48 hours from the initial dose of study medication post surgery.
• To be randomized after surgery, the patient must report moderate to severe pain (a score of 2 or more on the 4 point Likert scale or 4 or more on the 11 point NPRS scale).
• At least 40% of study subjects will be 60 years of age or older.

Exclusion Criteria:

• In the opinion of the Investigator, has a history of pulmonary, cardiovascular (including uncontrolled hypertension), neurologic, endocrine, hepatic, gastrointestinal, or kidney disease or therapy that would jeopardize the patient's well being by participation in this study or is mentally or emotionally unsuitable to participate, or unable/unwilling to comply with the study assessments.
• Used opiates continuously (including tramadol) for more than ten days in the past year.
• Hypersensitivity or poor tolerance to acetaminophen.
• Currently receiving any medications that are not at a stable dose (the same dose for > 2 months prior to date of surgery).
• Was dosed with another investigational drug within 30 days prior to the Screening Visit or has previously received treatment with Q8003.
• Current therapy with central nervous system depressant medications that might increase the risks of treatment with opioids (other than those used with surgical anesthesia).
• Current evidence of alcohol abuse (regularly drinks more than 4 units of alcohol per day; 1 unit = ½ pint of beer, 1 glass of wine, or 1 ounce of spirit).