Evaluation of study discontinuations with tapentadol immediate release and oxycodone immediate release in patients with low back or osteoarthritis pain

OBJECTIVE: To examine discontinuations due to nausea and/or vomiting or constipation with tapentadol immediate release (IR) or oxycodone IR treatment. DESIGN: Post hoc analyses of a 90-day, phase 3, randomized, double-blind, flexible-dose study. SETTING: United States, Canada, United Kingdom. PATIENTS: Adults with moderate to severe low back or osteoarthritis (OA) pain for > or =3 months. INTERVENTIONS: Tapentadol IR 50 or 100 mg or oxycodone HCI IR 10 or 15 mg every 4-6 hours as needed. MAIN OUTCOME MEASURES: Adverse events and discontinuations were recorded. RESULTS: Post hoc analyses included data from 679 patients receiving tapentadol IR and 170 receiving oxycodone IR (4:1 randomization). Tapentadol IR 50 or 100 mg and oxycodone HCI IR 10 or 15 mg provided similar levels of pain relief Overall, 21.2 percent of patients receiving tapentadol IR discontinued treatment for adverse events versus 31.2 percent of patients receiving oxycodone IR. The percentage of patients who discontinued for nausea and/or vomiting was significantly lower with tapentadol IR (5.9 percent) than oxycodone IR (14.7 percent; p = 0.0003); patients treated with oxycodone IR discontinued because of nausea and/or vomiting significantly earlier than with tapentadol IR (p < 0.0001). The percentage of patients who discontinued because of constipation was significantly lower with tapentadol IR (1.5 percent) than with oxycodone IR (5.9 percent; p = 0.0023); patients treated with oxycodone IR discontinued because of constipation significantly earlier versus tapentadol IR (p = 0.0003). CONCLUSIONS: A lower percentage of patients discontinued because of nausea and/or vomiting or constipation with tapentadol IR versus oxycodone IR while receiving comparable pain relief suggesting tapentadol may improve the management of low back and OA pain.