Efficacy and safety of tapentadol prolonged release for moderate-to-severe chronic osteoarthritis knee pain: a pooled analysis of two double-blind, randomized, placebo- and oxycodone controlled release-controlled studies

Objective: To compare efficacy and safety of tapentadol prolonged-release (PR) and oxycodone-controlled release (CR) in moderate-to-severe chronic osteoarthritis knee pain.

Methods: Data from two double-blind, randomized, placebo- and oxycodone CR-controlled phase 3 studies with a 3-week titration period and 12-week controlled dose adjustment maintenance period were pooled. Primary efficacy end-points were change from baseline in average pain intensity at week 12 (US end-point) and over the entire maintenance period (non-US end-point).

Results: A total of 2,010 patients were assessed. For both primary end-points, tapentadol PR was significantly more effective than oxycodone CR (LS mean difference of –0.41 [95% CI = –0.65, –0.16; p = 0.001] at week 12 and –0.35 [95% CI = –0.58, –0.12; p = 0.003] over 12 weeks of maintenance [last observation carried forward]). Significantly better outcomes than for oxycodone CR were also observed for patient global impression of change, both Short Form-36 component scores, and EuroQoL-5Dimensions health status index (all p < 0.001). Relative risk for vomiting, constipation, nausea, somnolence, and pruritus was lower for tapentadol PR than for oxycodone CR. A higher proportion of oxycodone CR patients discontinued treatment (64% vs 42.2% for tapentadol PR); time to treatment discontinuation due to an adverse event was significantly shorter for oxycodone CR (p < 0.001).

Conclusions: The analyses suggest that tapentadol PR provided superior pain relief and a more improved overall health status than oxycodone CR in a large patient population with moderate-to-severe chronic osteoarthritis pain. Compared to oxycodone CR, tapentadol PR showed a more favorable tolerability profile with better gastrointestinal tolerability.