Opioid-experienced (N = 250) patients with chronic, moderate to severe
low back pain (LBP) were converted from their prestudy
opioid(s) to an approximately equianalgesic dose of
OPANA ER (
oxymorphone extended release). Patients continued slow titration, with 56% stabilized within 1 month to a dose of
OPANA ER that reduced average
pain to <40 mm on a visual analog scale with good tolerability. Stabilized patients (n = 143) were randomized to placebo or their stabilized dose of
OPANA ER every 12 hours for a 12-week double-blind period.
Pain intensity increased significantly more for patients randomized to placebo than for patients who continued their stabilized dose of
OPANA ER; the increase from baseline (at randomization) to final visit was 31.6 mm for placebo versus 8.7 mm with
OPANA ER (P < .0001). During double-blind treatment, placebo patients were approximately 8-fold more likely than
OPANA ER patients to discontinue because of lack of efficacy (P < .001). Discontinuations as a result of adverse events were similar between groups, 10% with placebo and 11% with
OPANA ER.
Opioid-related adverse events included
constipation (6%),
somnolence (3%), and
nausea (3%). Fifty-seven percent of
opioid-experienced patients with chronic, moderate to severe LBP achieved a stable dose of
OPANA ER that was efficacious and generally well-tolerated for up to 12 weeks.
PERSPECTIVE: In a 12-week, double-blind, randomized, placebo-controlled trial in
opioid-experienced patients with chronic, moderate to severe LBP,
OPANA ER provided efficacious, long-term
analgesia and was generally well-tolerated.
OPANA ER may provide clinicians with a new treatment option for patients experiencing suboptimal
analgesic responses or poor tolerability with other
opioids.