To evaluate the efficacy and safety of an encapsulated, highly viscous formulation of extended-release oxycodone designed to resist common physical manipulation and chemical challenges (Remoxy; King Pharmaceuticals, Inc., Bristol, TV, which was acquired by Pfizer Inc. in March 2011).
An enriched enrollment randomized withdrawal trial design was used whereby patients entered a double-blind, multicenter, placebo-controlled trial after completing an open-label titration phase.
Sixty-one US clinics.
All patients (40-75 years) had experienced moderate to severe chronic osteoarthritic pain in the hip or knee for > or = 3 months.
During 2 weeks of open-label treatment (N = 558), patients were titrated from Remoxy 5 mg twice daily (bid) to 20 mg bid. Patients who tolerated the drug were randomly assigned to Remoxy or placebo bid for 12 weeks. Dose titration was permitted during weeks 1-4 (range, 10-80 mg/d) and fixed thereafter.
The area under the curve (AUC) for change in pain intensity (PI) scores from prerandomization to the end of the 12-week period was the primary endpoint. Patient assessment of quality of analgesia, global assessment of study medication, quality of life, and safety were also evaluated.
The mean AUC for change in PI score was significantly greater for Remoxy than for placebo (p = 0.007). Patients receiving Remoxy reported significantly better scores on quality of analgesia (p = 0.004) and global assessment of study medication (p = 0.007) when compared with patients receiving placebo. Remoxy had a safety profile consistent with other opioids.
Remoxy significantly improved analgesia among patients with moderate to severe chronic osteoarthritic pain with an adverse event profile similar to other opioids.