Pfizer announced results from three pivotal studies of investigational ALO-02 (oxycodone hydrochloride and naltrexone extended-release capsules) at the American Pain Society (APS) Annual Meeting.

The Phase 3 trial was a 12-week, double-blind, placebo-controlled, randomized withdrawal 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 during the 4–6 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).

Results demonstrated that the mean changes in the primary endpoint, as measured by the numerical rating scale (NRS-pain) scores from baseline to the final two weeks, were statistically significant between ALO-02 and placebo. In the ALO-02 group, 84 (57.5%) had at least a 30% decrease (improvement) in NRS-pain score from screening compared to 59 (44.0%) patients in the placebo group (p=0.0248).

RELATED:Hydrocodone Extended-Release Tabs Effective in Pain Trial

The first of the two abuse-potential studies compared the abuse potential of ALO-02 and immediate-release (IR) oxycodone when taken orally. The randomized, double-blind, double-dummy, placebo- and active-controlled, 6-way crossover study in 41 healthy, non-dependent, recreational opioid users demonstrated that oral administration of 40mg (crushed) and 60mg ALO-02 (crushed or intact) resulted in statistically significant lower scores for Drug Liking and High than equivalent doses of crushed IR oxycodone.

A second abuse-potential study compared the abuse potential of crushed ALO-02 with crushed IR oxycodone and placebo when administered intranasally. The randomized, double-blind, placebo- and active-controlled, 4-way crossover study in 32 healthy, non-dependent, recreational opioid users demonstrated that intranasal administration of crushed 30 mg ALO-02 resulted in statistically significant lower scores for Drug Liking and High relative to crushed 30 mg IR oxycodone.

ALO-02 contains pellets of extended-release oxycodone hydrochloride, an opioid agonist, which surround sequestered naltrexone hydrochloride, an opioid receptor antagonist. When used as directed, naltrexone remains sequestered and patients receive oxycodone in an extended release manner. If the pellets are crushed, naltrexone is released and is designed to counteract the effects of oxycodone.

For more information call (484) 865-5194 or visit