Pfizer Inc. (NYSE: PFE) announced today top-line results from a Phase 3 study of investigational agent ALO-02 (oxycodone hydrochloride and naltrexone hydrochloride extended-release capsules) in patients with moderate-to-severe chronic low back pain. In this study, ALO-02 met the primary efficacy endpoint, demonstrating a statistically significant difference from placebo.
This was a 12-week, double-blind, placebo-controlled, randomized withdrawal design efficacy and safety study in patients with moderate-to-severe chronic low back pain. Patients who achieved a stable and effective dose of ALO-02 (10-80 mg twice per day) during the 4-to-6 week, open-label titration period were randomized (n=281) to the 12-week, double-blind period in which they were either maintained on their current dose regimen of ALO-02 (n=147) or were tapered to placebo (n=134). The primary efficacy endpoint of the study was defined as the difference between ALO-02 and placebo in the mean change in the daily average pain numerical rating scale (NRS-Pain) scores from baseline (just prior to randomization) to the final two weeks of the double-blind treatment period. Pain was self-reported daily on an 11-point numeric rating scale (daily NRS; 0=no pain, 10=worst possible pain). Mean changes in the primary endpoint, NRS-Pain scores from baseline to the final 2 weeks, were significantly different between ALO-02 and placebo.
The most common adverse events with ALO-2 during the double-blind period in this study were nausea, vomiting and diarrhea.
Results from this study will be submitted for presentation at upcoming medical congresses and submitted for publication in a peer-reviewed journal.
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