A Randomized Withdrawal, Placebo-Controlled Study Evaluating the Efficacy and Tolerability of Tapentadol Extended Release in Patients With Chronic Painful Diabetic Peripheral Neuropathy

OBJECTIVE This study evaluated the efficacy and tolerability of tapentadol extended release (ER) for the management of chronic pain associated with diabetic peripheral neuropathy (DPN). RESEARCH DESIGN AND METHODS Adults with moderate to severe DPN pain were titrated to tapentadol ER 100–250 mg bid during a 3-week open-label period; patients with ≥1-point reduction in pain intensity (11-point numerical rating scale) at end of titration were randomized to receive placebo or tapentadol ER (optimal dose from titration) for 12 weeks (double-blind, fixed-dose maintenance phase). The primary end point was mean change in average pain intensity from the start to week 12 (last observation carried forward [LOCF]) of the double-blind maintenance phase. RESULTS A total of 358 patients completed the titration period; 318 patients (placebo, n = 152; tapentadol ER, n = 166) were randomized and received one or more doses of double-blind study medication. Mean (SD) pain intensity (observed case) was 7.33 (1.30) at the start and 4.16 (2.12) at week 3 of the open-label titration period (mean [SD] change, –3.22 [1.97]). The mean (SD) change in pain intensity (LOCF) from start of double-blind treatment to week 12 was as follows: placebo, 1.30 (2.43); tapentadol ER, 0.28 (2.04; least squares mean difference, –0.95 [95% CI –1.42 to –0.49]; P CONCLUSIONS Tapentadol ER (100–250 mg bid) was effective and well tolerated for the management of moderate to severe chronic pain associated with DPN.