The efficacy and safety of graded doses (10, 20, and 30 mg) of controlled-release (CR)
oxycodone was compared with that of immediate-release (IR)
oxycodone (15 mg), immediate-release
oxycodone 10 mg in combination with
acetaminophen 650 mg (
APAP), and placebo in a single-dose, double-blind, randomized, parallel-group study. The participants, 182 inpatients experiencing moderate to severe
pain after abdominal or
gynecologic surgery, provided hourly ratings of
pain intensity and relief for 12 hours after administration. All active treatments were significantly superior to placebo for many hourly measurements and for the sum of
pain intensity differences (SPID) and total
pain relief (TOTPAR). A dose response was found among the three levels of CR
oxycodone for
pain relief and peak
pain intensity difference (PID), with the 20- and 30-mg doses being significantly better than the 10-mg dose. For all active treatments, peak PID and peak
pain relief occurred approximately 2 to 4 hours after administration. The median time to onset of relief was 32 minutes for
oxycodone plus
APAP, 41 minutes for IR
oxycodone, and 46 minutes for CR
oxycodone 30 mg. Duration of
pain relief showed that the 10-, 20-, and 30-mg doses of CR
oxycodone had durations of action of 10 to 12 hours compared with IR
oxycodone and
oxycodone plus
APAP (both approximately 7 hours). Typical adverse events, particularly
somnolence, occurred in all active treatment groups. Treatment with CR
oxycodone was safe and effective in this study, and its characteristics will be beneficial in the treatment of
pain.