Two separate trials compared controlled-release (CR) oral
oxycodone (administered every 12 hours) with immediate-release (IR)
oxycodone (4 times a day) to determine whether patients with
chronic pain could be titrated to stable
pain control as readily with the CR as with the IR formulation. In one study, 48 patients with
cancer pain were randomized to open-label titration with either CR or IR
oxycodone (maximum dose, 400 mg/day) for a period of up to 21 days. In a study of similar design, 57 patients with
low back pain were titrated with either CR or IR
oxycodone (maximum dose, 80 mg/day) for a period of up to 10 days. The majority of patients in both studies were converted to
oxycodone from other
opioid analgesics. Results of both studies showed no difference between CR and IR
oxycodone with respect to both the percentage of patients achieving stable
pain control, the time to achieve stable
pain control, and the degree of
pain control achieved. Among
cancer patients, 85% achieved stable
analgesia, 92% with the CR formulation and 79% with the IR formulation. Among noncancer patients, 91% achieved stable
pain control, 87% with the CR formulation and 96% with the IR formulation. The most commonly reported adverse effects in both studies were similar for the two formulations and were those anticipated with
opioids:
nausea,
vomiting,
constipation,
somnolence,
dizziness, and
pruritus.
Nausea and
vomiting were the most frequently cited reasons for treatment discontinuations. These studies suggest that dose titration can be accomplished as readily with oral CR
oxycodone as with IR
oxycodone in patients with chronic, moderate to severe
pain.