Comparison of Two KADIAN 10 mg Capsules to a KADIAN 20 mg Capsule Under Fasted Conditions

Inclusion Criteria: * Subject must be a male or non-pregnant, non-breast-feeding female. * Subject must be between 18 and 55 years of age (inclusive). * Subject's Body Mass Index (BMI) must be between 18 and 30 kg/m2 (inclusive), and subject must weigh a minimum of 50 kg (110 lbs). * Female subjects - not surgically sterile or at least two years postmenopausal - must agree to utilize one of the following forms of contraception, if sexually active with a male partner, at least from screening through completion of the study. Approved forms of contraception are abstinence, hormonal (oral, implant, transdermal or injection) in use at least 3 consecutive months prior to first dose of study medication, double barrier (condom and diaphragm with spermicide), intra-uterine device (IUD), or vasectomized partner (6 months minimum since vasectomy). * Subject must voluntarily consent to participate in this study and provide their written informed consent prior to completion of any study-specific procedures. * Subject is willing and able to remain in the study unit for the entire duration of each confinement period and return to the study site for all outpatient visits. Exclusion Criteria: * History or presence of clinically significant cardiovascular, pulmonary, hepatic, renal, hematologic, gastrointestinal, endocrine, immunologic, dermatologic, neurologic, oncologic or psychiatric disease or any other condition which, in the opinion of the Investigator would jeopardize the safety of the subject or the validity of the study results. * Has a clinically significant abnormal finding on the physical exam, medical history, ECG or clinical laboratory results at screening. * History or presence of allergic or adverse response to the KADIAN or related drugs. * Has been on a significantly abnormal diet during the four weeks preceding the first dose of study medication. * Has donated blood or plasma within 30 days prior to the first dose of study medication. * Has participated in another clinical trial within 30 days prior to first dose of study medication. * Has used any over-the-counter (OTC) medication including nutritional supplements, within 7 days prior to the first dose of study medication. * Has used any prescription medication, except hormonal contraceptive or hormonal replacement therapy, within 14 days prior to the first dose of study medication. * Has been treated with any known enzyme altering drugs such as barbiturates, phenothiazines, cimetidine, carbamazepine, etc., within 30 days prior to the first dose of study medication. * Has smoked or used tobacco products within 60 days prior to the first dose of study medication. * Has a history of treatment for substance abuse (including alcohol) in the past 5 years. * Is a female with a positive pregnancy test result. * Has a positive urine screen for drugs of abuse (amphetamines, barbiturates, benzodiazepines, cocaine, cannabinoids, opiates). * Has had a positive test for, or has been treated for Hepatitis B, Hepatitis C or HIV.