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Background Understanding how patients are treated in the real-world is vital to identifying potential gaps in care. We describe the current pharmacologic treatment patterns for the treatment of depression. Methods Patients with depression were identified from four large national claims databases during 1/1/2014–1/31/2019. Patients had ≥2 diagnoses for depression or an inpatient hospitalization with a diagnosis of depression. Patients were required to have enrollment in the database ≥1 year prior to and 3 years following their first depression diagnosis. Treatment patterns were captured at the class level and included selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors, tricyclic antidepressants, other antidepressants, anxiolytics, hypnotics/sedatives, and antipsychotics. Treatment patterns were captured during all available follow-up. Results We identified 269,668 patients diagnosed with depression. The proportion not receiving any pharmacological treatment during follow-up ranged from 29 to 52%. Of the treated, approximately half received ≥2 different classes of therapy, a quarter received ≥3 classes and more than 10% received 4 or more. SSRIs were the most common first-line treatment; however, many patients received an anxiolytic, hypnotic/sedative, or antipsychotic prior to any antidepressive treatment. Treatment with a combination of classes ranged from approximately 20% of first-line therapies to 40% of fourth-line. Conclusions Many patients diagnosed with depression go untreated and many others receive a non-antidepressant medication class as their first treatment. More than half of patients received more than one type of treatment class during the study follow up, suggesting that the first treatment received may not be optimal for most patients.

Background This is the first clinical trial in the global pediatric clinical development program for the use of the analgesic tapentadol in children and adolescents. Patients and methods This multicenter, open-label clinical trial investigated pharmacokinetics, safety and tolerability, and efficacy of tapentadol and its major metabolite tapentadol-O-glucuronide after administration of a single dose of tapentadol oral solution (OS) in pediatric patients aged 6 to

Following a partial response of first-line antidepressant therapy for the treatment of major depressive disorder (MDD), there is a choice to augment treatment with another agent or switch to a different antidepressant.To report the prevalence and compare the characteristics of patients switching from their initial selective serotonin reuptake inhibitor or serotonin-norepinephrine reuptake inhibitor (SSRI/SNRI) to a new SSRI/SNRI versus those augmenting SSRI/SNRI therapy with a second-generation antipsychotic (SGA).MDD patients receiving first-line SSRI/SNRI treatment were identified from a large US-based claims database during 2000-2019. Patients augmenting therapy with an SGA were compared with those who switched to a new SSRI/SNRI. The date of the treatment change was the index date. Previously diagnosed comorbid conditions, medication use and demographics were captured. Treatment patterns following the index date were also captured. Standardized differences (StdDiff) were used to quantify dissimilarities between the two groups.There were 4572 SGA add-on and 24,409 switching patients identified. SGA augmentation patients had more severe disease (diagnosed severe recurrent major depression: 24.7% vs. 9.5%, StdDiff = 0.41) and more diagnosed psychiatric conditions, including: suicidal thoughts (10.7% vs. 3.2%, StdDiff = 0.29), post-traumatic stress disorder (6.1% vs. 2.6%, StdDiff = 0.17) and alcohol abuse (5.4% vs. 2.7%, StdDiff = 0.14). SGA augmentation patients had higher rates of prior use of anxiolytics (37.4% vs. 28.2%, StdDiff = 0.20) and anticonvulsants (26.0% vs. 13.1%, StdDiff = 0.33).Patients adding an SGA to their SSRI/SNRI therapy appeared to have more severe depression and comorbid psychiatric profile than those switching their SSRI/SNRI. These differences are important to consider and adequately control for in any future comparative outcome research between these two groups.

There is tremendous interpatient variability in the response to analgesic therapy (even for efficacious treatments), which can be the source of great frustration in clinical practice. This has led to calls for “precision medicine” or personalized pain therapeutics (ie, empirically based algorithms that determine the optimal treatments, or treatment combinations, for individual patients) that would presumably improve both the clinical care of patients with pain and the success rates for putative analgesic drugs in phase 2 and 3 clinical trials. However, before implementing this approach, the characteristics of individual patients or subgroups of patients that increase or decrease the response to a specific treatment need to be identified. The challenge is to identify the measurable phenotypic characteristics of patients that are most predictive of individual variation in analgesic treatment outcomes, and the measurement tools that are best suited to evaluate these characteristics. In this article, we present evidence on the most promising of these phenotypic characteristics for use in future research, including psychosocial factors, symptom characteristics, sleep patterns, responses to noxious stimulation, endogenous pain-modulatory processes, and response to pharmacologic challenge. We provide evidence-based recommendations for core phenotyping domains and recommend measures of each domain.

Background Seltorexant, a selective antagonist of human orexin-2 receptors, demonstrated antidepressant effects in a previous exploratory study in patients with major depressive disorder (MDD). Methods To replicate and extend this observation, a double-blind, adaptive dose-finding study was performed in patients with MDD who had an inadequate response to 1–3 selective serotonin/serotonin-norepinephrine reuptake inhibitors in the current episode. Patients were randomized (2:1:1) to placebo or seltorexant (20 mg or 40 mg) once-daily, administered adjunctively to the antidepressant the patient had been receiving at screening. After an interim analysis (6 weeks post-randomization of 160th patient), newly recruited patients randomly received (3:3:1) placebo or seltorexant 10 mg or 20 mg; the 40-mg dose was no longer assigned. Patients were stratified by baseline Insomnia Severity Index (ISI) scores (ISI ≥ 15 vs Results Mixed-Model for Repeated Measures analysis showed a greater improvement in MADRS total score in the seltorexant 20-mg group vs placebo at weeks 3 and 6; least-square means difference (90% CI): −4.5 (−6.96; −2.07), P = .003; and −3.1 (−6.13; −0.16), P = .083, respectively. The improvement in MADRS score at week 6 for seltorexant 20 mg was greater in patients with baseline ISI ≥ 15 vs those with ISI < 15; least-square means difference (90% CI) vs placebo: −4.9 (−8.98; −0.80) and −0.7 (−5.16; 3.76), respectively. The most common (≥5%) adverse events with seltorexant were somnolence, headache, and nausea. Conclusions A clinically meaningful reduction of depressive symptoms was observed for seltorexant 20 mg. In the subset of patients with sleep disturbance (ISI ≥ 15), a larger treatment difference between seltorexant 20 mg and placebo was observed, warranting further investigation. No new safety signal was identified. Registration ClinicalTrials.gov Identifier: NCT03227224 Previous presentation Poster presented at 58th Annual Meeting of American College of Neuropsychopharmacology (ACNP), December 8–11, 2019, Orlando, FL.

Background and Objective Data from two similarly designed studies of tapentadol extended release (ER) for managing neuropathic pain associated with diabetic peripheral neuropathy (DPN; NCT00455520, NCT01041859) in adults were pooled for this analysis, allowing a detailed evaluation of efficacy in patient subgroups and secondary endpoints. Methods In each study, patients were titrated to their optimal dose of open-label tapentadol ER [100–250 mg twice daily (bid)] over 3 weeks. Patients with ≥1-point improvement in average pain intensity [11-point numerical rating scale (NRS)] were randomized (1:1) to receive placebo or tapentadol ER during a 12-week, double-blind maintenance period. Results Mean (standard deviation [SD]) changes in pain intensity from baseline to week 12 of maintenance in the placebo (n = 343) and tapentadol ER (n = 360) groups, respectively, were 1.28 (2.41) and 0.08 (1.87) [least squares mean difference (LSMD): −1.14 (95 % confidence interval [CI]: −1.435, −0.838); P

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 < 0.001). Treatment-emergent adverse events (≥10%) in the tapentadol ER group during the double-blind maintenance phase were nausea (21.1%) and vomiting (12.7%). CONCLUSIONS Tapentadol ER (100–250 mg bid) was effective and well tolerated for the management of moderate to severe chronic pain associated with DPN.

Background and Objectives Hypertension is one of the most common co-existing conditions in patients with chronic pain, and the potential effects of an analgesic on heart rate and blood pressure are of particular concern for patients with hypertension. The purpose of this analysis was to evaluate changes in blood pressure and heart rate with tapentadol extended release (ER) treatment in patients with hypertension. Methods We performed a post hoc analysis of data pooled from three randomized, placebo- and active-controlled, phase III studies of tapentadol ER for managing chronic osteoarthritis knee (NCT00421928, NCT00486811) or low back (NCT00449176) pain (15-week, double-blind treatment period). Data were independently analyzed for patients with a listed medical history of hypertension at baseline and patients with at least one listed concomitant antihypertensive medication at baseline. Heart rate, systolic blood pressure (SBP), and diastolic blood pressure (DBP) were measured at each visit. Results In patients with a listed medical history of hypertension (n = 1,464), least-squares mean (LSM [standard error (SE)]) changes from baseline to endpoint with placebo, tapentadol ER, and oxycodone HCl controlled release (CR), respectively, were −0.7 (0.44), 0.2 (0.43), and −0.9 (0.45) beats per minute (bpm) for heart rate; −2.4 (0.64), −2.7 (0.64), and −3.7 (0.67) mmHg for SBP; and −1.0 (0.39), −1.3 (0.39), and −2.3 (0.41) mmHg for DBP; in patients with at least one listed concomitant antihypertensive medication (n = 1,376), the LSM (SE) changes from baseline to endpoint were −0.6 (0.45), 0.1 (0.44), and −0.7 (0.47) bpm for heart rate; −1.8 (0.66), −3.3 (0.65), and −3.7 (0.69) mmHg for SBP; and −0.7 (0.40), −1.4 (0.40), and −2.3 (0.42) mmHg for DBP. Conclusion No clinically meaningful mean changes in heart rate or blood pressure were observed for the evaluated cohorts of patients with hypertension who were treated with tapentadol ER (100–250 mg twice daily).

Objective: To evaluate tamper-resistant properties of tapentadol tablets formulated with polyethylene oxide (PEO) matrix. Design: Analytical and physical tests to characterize tablets. Interventions: Tapentadol extended release (ER) 50, 100, 150, 200, and 250 mg. Main outcome measure(s): Mechanical resistance of tapentadol ER tablets to crushing (all doses), in vitro drug-release profiles of intact and tampered 50- and 250-mg tablets, and resistance to extraction of 250-mg tablets subjected to hammering. Results: Crush resistance testing showed no deformation of tablets with two metal spoons, minimal deformation (no pulverization/breakage) with a pill crusher, slight deformation with a standardized pharmacopeia breaking force tester, and flattening (no pulverization/breakage) with a standardized hammer instrument. Mean in vitro release profiles in quality control medium (0.050 M phosphate buffer, pH 6.8) were similar with intact and tampered (pill crusher) tablets; the release profile was faster for hammered than intact tablets, with 30 percent of the drug released after 30 minutes (slightly higher than maximum release allowed per drug product specifications). Intact tablets were completely resistant to extraction in most organic solvents tested; in aqueous solvents, the amount of drug extracted increased with time. Hammered tablets were less resistant to extraction but required vigorous shaking over extended periods of time to release >50 percent of active ingredient. Conclusions: In vitro results from tampering attempts presented herein demonstrate that tapentadol ER tablets were resistant to these forms of physical manipulation. Tapentadol ER tablets were also generally resistant to dissolution in most solvents. Developing tamper-resistant formulations is an important step in strategies to mitigate opioid abuse.

Tapentadol extended release (ER) is approved for the management of chronic and acute pain in adults. There has been no report of tapentadol ER pharmacokinetics in subjects with cancer pain. This analysis investigated tapentadol ER pharmacokinetics in Japanese patients with cancer pain and bridged it with the pharmacokinetics in Japanese healthy subjects and Caucasian patients with cancer pain. Nonlinear mixed-effect pharmacokinetic modeling was conducted based on pooled tapentadol ER concentration data collected in five Phase 1 studies from 138 Japanese and Korean healthy subjects and in two Phase 3 studies from 215 Japanese and Korean subjects with cancer pain. Expected tapentadol exposure in subjects with different characteristics was assessed via simulation. Tapentadol ER exposures in Caucasian populations were compared with those in corresponding Japanese populations. Tapentadol ER pharmacokinetics in Japanese cancer-pain patients were adequately described by a time-invariant, one-compartment disposition model with two input functions and first-order elimination. Weight, age, and albumin were identified as statistically significant covariates, but do not warrant dose adjustment. Comparable pharmacokinetics were shown between Japanese healthy and Caucasian healthy subjects, and between Japanese cancer-pain patients and Caucasian cancer-pain patients. The apparent differences in the estimated individual pharmacokinetic parameters in Japanese healthy subjects and Japanese cancer-pain patients taking tapentadol ER were explained by covariates incorporated in a unified pharmacokinetic model. Population modeling was essential in this cross-population bridging analysis.

Background: The efficacy of tapentadol extended release (ER) for managing chronic pain has been demonstrated in large-scale, randomized, controlled, phase 3 studies (N=318–1,030) in patients with chronic osteoarthritis (OA) pain, low back pain (LBP), and pain related to diabetic peripheral neuropathy (DPN), which led to registration in many regions, including the United States and Europe. 2 pilot 12-week, randomized, double-blind, placebo-controlled phase 2 studies of tapentadol ER for chronic pain (OA knee pain or LBP, n=91; DPN or peripheral herpetic neuralgia [PHN] pain; n=91) were conducted in Japan. These small exploratory studies were substantially underpowered compared with the registration trials. Methods: Patients in both studies were randomized (2:1) to tapentadol ER (25–250 mg) or placebo for 12 weeks (≤6-week titration plus maintenance periods). Results: For the primary efficacy endpoint (change in pain intensity from baseline to last week of treatment; last observation carried forward), both studies failed to differentiate between tapentadol ER and placebo; least-squares mean differences (95% confidence intervals) for tapentadol ER vs. placebo were −0.1 (−1.04, 0.80) in the OA/LBP study and −0.1 (−1.10, 0.99) in the DPN/PHN study. More than 80% of patients took concomitant analgesics during these studies. Tapentadol was well tolerated. Conclusions: Both studies were associated with methodological issues, including populations with different disease entities, small sample sizes, use of concomitant analgesics, and possible placebo effect that may have led to the failure to differentiate between tapentadol ER and placebo.

Clinical trial participants often require additional instruction to prevent idiosyncratic interpretations regarding completion of patient-reported outcomes. The Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION) public-private partnership developed a training system with specific, standardized guidance regarding daily average pain intensity ratings. A 3-week exploratory study among participants with low-back pain, osteoarthritis of the knee or hip, and painful diabetic peripheral neuropathy was conducted, randomly assigning participants to 1 of 3 groups: training with human pain assessment (T+); training with automated pain assessment (T); or no training with automated pain assessment (C). Although most measures of validity and reliability did not reveal significant differences between groups, some benefit was observed in discriminant validity, amount of missing data, and ranking order of least, worst, and average pain intensity ratings for participants in Group T+ compared with the other groups. Prediction of greater reliability in average pain intensity ratings in Group T+ compared with the other groups was not supported, which might indicate that training produces ratings that reflect the reality of temporal pain fluctuations. Results of this novel study suggest the need to test the training system in a prospective analgesic treatment trial.

Objective: Management of chronic pain in elderly adult patients is often complicated by analgesic medication–related side effects. This post hoc analysis of pooled data evaluated the tolerability and analgesic efficacy of tapentadol extended release (ER) compared with oxycodone controlled release (CR) in elderly adult patients ( ≥ 75 years of age) with moderate to severe, chronic osteoarthritis knee or low back pain. Methods: Data were pooled from three similarly designed, randomized, double-blind, placebo- and active-controlled, phase 3 studies of tapentadol ER for moderate to severe, chronic osteoarthritis knee (NCT00421928, NCT00486811) or low back (NCT00449176) pain, and data for patients ≥ 75 years of age were evaluated. Each study consisted of a 3-week titration and 12-week maintenance period. Patients received placebo, tapentadol ER (100-250 mg bid), or oxycodone HCl CR (20-50 mg bid). Tolerability was evaluated using adverse event reporting. Efficacy was evaluated using pain intensity ratings (11-point numerical rating scale). Results: For patients ≥ 75 years of age (n = 210), incidences of gastrointestinal treatment-emergent adverse events (TEAEs) overall and TEAEs of vomiting and the composite of nausea and/or vomiting were significantly lower in the tapentadol ER group compared with the oxycodone CR group (all p ≤ 0.0206). Tapentadol ER treatment was associated with significant reductions in pain intensity from baseline to week 15 compared with placebo (p = 0.0075); differences between the oxycodone CR and placebo groups failed to reach statistical significance (p = 0.1195), likely related to a higher treatment discontinuation rate in the oxycodone CR group. No significant differences were observed between the tapentadol ER and oxycodone CR groups in the change in pain intensity from baseline to week 15 (p = 0.2135). Conclusions: In elderly adult patients ≥ 75 years of age with moderate to severe, chronic osteoarthritis knee or low back pain, tapentadol ER (100-250 mg bid) provided significant pain relief compared with placebo and had a better overall gastrointestinal tolerability profile than oxycodone CR.

Painful diabetic peripheral neuropathy (DPN) may not be adequately managed with available therapeutic options. This phase III, randomized-withdrawal, placebo-controlled trial evaluated the safety and efficacy of tapentadol extended release (ER) for relieving painful DPN.Patients (n = 588) with at least a 3-month history of opioid and/or non-opioid analgesic use for DPN, dissatisfaction with current treatment, and an average pain intensity score of at least 5 on an 11-point numerical rating scale (NRS; 0 = 'no pain,' 10 = 'pain as bad as you can imagine') were titrated to an optimal dose of tapentadol ER (100-250 mg bid) during a 3-week open-label phase. Subsequently, patients (n = 395) with at least a 1-point reduction in pain intensity were randomized 1:1 to receive placebo or the optimal fixed dose of tapentadol ER determined during the open-label phase for a 12-week double-blind phase.NCT00455520.The primary efficacy outcome was the change in average pain intensity from randomization, determined by twice-daily NRS measurements. Safety was assessed throughout the study.The least-squares mean difference between groups in the change in average pain intensity from the start of double-blind treatment to week 12 was -1.3 (95% confidence interval, -1.70 to -0.92; p 0.001, tapentadol ER vs. placebo). A total of 60.5% (356/588) of patients reported at least a 30% improvement in pain intensity from the start to the end of the open-label titration phase; of the patients who were randomized to tapentadol ER, 53.6% (105/196) reported at least a 30% improvement from pre-titration to week 12 of the double-blind phase. The most common treatment-emergent adverse events that occurred during double-blind treatment with tapentadol ER included nausea, anxiety, diarrhea, and dizziness. Potential limitations of this study are related to the enriched enrollment randomized-withdrawal trial design, which may result in a more homogeneous patient population during double-blind treatment and may present a risk of unblinding because of changes in side effects from the open-label to the double-blind phase.Compared with placebo, tapentadol ER 100-250 mg bid provided a statistically significant difference in the maintenance of a clinically important improvement in pain 1 , 2 and was well-tolerated by patients with painful DPN.

Background: Tapentadol is a novel, centrally acting analgesic with 2 mechanisms of action: µ-opioid receptor agonism and norepinephrine reuptake inhibition. This randomized, open-label phase 3 study (ClinicalTrials.gov Identifier: NCT00361504) assessed the long-term safety and tolerability of tapentadol extended release (ER) in patients with chronic knee or hip osteoarthritis pain or low back pain. Methods: Patients were randomized 4:1 to receive controlled, adjustable, oral, twice-daily doses of tapentadol ER (100 to 250 mg) or oxycodone HCl controlled release (CR; 20 to 50 mg) for up to 1 year. Efficacy evaluations included assessments at each study visit of average pain intensity (11-point numerical rating scale) over the preceding 24 hours. Treatment-emergent adverse events (TEAEs) and discontinuations were monitored throughout the study. Results: A total of 1,117 patients received at least 1 dose of study drug. Mean (standard error) pain intensity scores in the tapentadol ER and oxycodone CR groups, respectively, were 7.6 (0.05) and 7.6 (0.11) at baseline and decreased to 4.4 (0.09) and 4.5 (0.17) at endpoint. The overall incidence of TEAEs was 85.7% in the tapentadol ER group and 90.6% in the oxycodone CR group. In the tapentadol ER and oxycodone CR groups, respectively, TEAEs led to discontinuation in 22.1% and 36.8% of patients; gastrointestinal TEAEs led to discontinuation in 8.6% and 21.5% of patients. Conclusion: Tapentadol ER (100 to 250 mg bid) was associated with better gastrointestinal tolerability than oxycodone HCl CR (20 to 50 mg bid) and provided sustainable relief of moderate to severe chronic knee or hip osteoarthritis or low back pain for up to 1 year.

Background: Tapentadol is a novel, centrally acting analgesic with μ-opioid receptor agonist and norepinephrine reuptake inhibitor activity. Objective: To evaluate the efficacy and safety of tapentadol extended release (ER) compared with oxycodone controlled release (CR) for management of moderate to severe chronic osteoarthritis-related knee pain. Methods: This was a randomized, double-blind, active- and placebo-controlled, parallel-arm, multicentre, phase III study during which patients received tapentadol ER, oxycodone CR or placebo for a 3-week titration period followed by a 12-week maintenance period. The study was carried out at sites in Australia, Canada, New Zealand and the US. A total of 1030 patients with chronic osteoarthritis-related knee pain were randomized to receive tapentadol ER 100–250 mg twice daily, oxycodone HCl CR 20–50 mg twice daily or placebo. Primary endpoints (as determined prior to initiation of the study) were the changes from baseline in average daily pain intensity (rated by patients on an 11-point numerical rating scale) over the last week of maintenance and over the entire 12-week maintenance period; last observation carried forward was used to impute missing values after early treatment discontinuation. Results: Efficacy and safety were evaluated for 1023 patients. Tapentadol ER significantly reduced average pain intensity from baseline to week 12 of the maintenance period versus placebo (least squares mean [LSM] difference [95% CI], −0.7 [−1.04, −0.33]), and throughout the maintenance period (−0.7 [−1.00, −0.33]). Oxycodone CR significantly reduced average pain intensity from baseline throughout the maintenance period versus placebo (LSM difference [95% CI], −0.3 [−0.67, −0.00]) but not at week 12 (−0.3 [−0.68, 0.02]). A significantly higher percentage of patients achieved ≥50% improvement in pain intensity in the tapentadol ER group (32.0% [110/344]) compared with the placebo group (24.3% [82/337]; p = 0.027), indicating a clinically significant improvement in pain intensity, while a significantly lower percentage of patients achieved ≥50% improvement in pain intensity in the oxycodone CR group (17.3% [59/342]; p = 0.023 vs placebo). In the placebo, tapentadol ER and oxycodone CR groups, respectively, 61.1% (206/337), 75.9% (261/344) and 87.4% (299/342) of patients reported at least one treatment-emergent adverse event (TEAE); incidences of gastrointestinal-related TEAEs were 26.1% (88/337), 43.0% (148/344) and 67.3% (230/342). Conclusion: Treatment with tapentadol ER 100–250 mg twice daily or oxycodone HCl CR 20–50 mg twice daily was effective for the management of moderate to severe chronic osteoarthritis-related knee pain, with substantially lower incidences of gastrointestinal-related TEAEs associated with treatment with tapentadol ER than with oxycodone CR. [Trial registration number: NCT00421928 (ClinicalTrials.gov Identifier)]

Background: Tapentadol, a novel, centrally acting analgesic with 2 mechanisms of action (µopioid receptor agonism and norepinephrine reuptake inhibition), has been developed in an immediate-release (IR) and an extended-release (ER) formulation. Determination of the safety and equianalgesic ratios for conversion between formulations is important for physicians with patients taking tapentadol IR who may want to switch to tapentadol ER, or vice versa, for any reason. Objectives: To test whether the total daily dose (TDD) of tapentadol IR may be directly converted into a comparable TDD of tapentadol ER, and vice versa, with equivalent efficacy and comparable safety. Study Design: Randomized, double-blind, 2-period (2 weeks each) crossover study. Setting: Study centers (N = 13) in the United States. Methods: Patients with moderate to severe chronic low back pain received tapentadol IR 50, 75, or 100 mg every 4 or 6 hours (maximum TDD, 500 mg) during the 3-week open-label period to identify an optimal, stable dose of tapentadol IR for each patient. Patients were then randomized in a 1:1 ratio to receive, during the first 2-week double-blind period, either the optimal dose of tapentadol IR identified during the open-label period or a TDD of tapentadol ER (100, 150, 200, or 250 mg bid) that was as close as possible to the TDD of tapentadol IR from the open-label period. During a subsequent, 2-week double-blind period, patients received whichever formulation was not received during the first double-blind period. The primary endpoint was the mean average daily pain intensity (on an 11-point numerical rating scale) during the last 3 days of each double-blind treatment period. If the 95% confidence intervals (CIs) of the least squares mean difference between formulations were within the range of −2 to 2, the formulations were considered equivalent. Results: Of the 88 patients who were randomized, 72 completed both double-blind treatments, and 60 were included in the per-protocol analysis. The mean (standard deviation [SD]) pain intensity score decreased from 7.3 (1.19) pre-treatment to 4.2 (2.13) after 3 weeks of open-label treatment with tapentadol IR and remained constant throughout double-blind treatment (3.9 or 4.0 each week) for both formulations. The mean (SD) of the average pain intensity scores over the last 3 days of double-blind treatment was 3.9 (2.17) with tapentadol IR and 4.0 (2.29) with tapentadol ER, for an estimated difference of 0.1 (95% CI, −0.09 to 0.28). For both tapentadol IR and tapentadol ER, the median TDD administered was 300.0 mg, and acetaminophen was used by 39.5% and 45.2% of patients, respectively. The incidence of treatment-emergent adverse events during double-blind treatment was similar between the tapentadol IR and tapentadol ER groups. Limitations: Use of rescue medication theoretically could have influenced pain measurements, but in practice, pain measurements did not differ between treatments. Conclusions: Approximately equivalent TDDs of tapentadol IR and tapentadol ER provided equivalent analgesic efficacy for the relief of moderate to severe chronic low back pain and were similarly well tolerated, allowing for direct conversion between the 2 formulations. Key words: Chronic low back pain, conversion, efficacy, equivalence, extended release, immediate release, opioid, safety, tapentadol

Objectives: Opioid-induced androgen deficiency (OPIAD) affects patients treated with opioid analgesics. The norepinephrine reuptake inhibitor (NRI) and μ-opioid receptor (MOR) agonist activities of tapentadol may result in tapentadol having less effect on serum androgen concentrations than analgesics acting through the MOR alone, such as morphine and oxycodone. The objectives of this publication are to 1) evaluate the effects of tapentadol (NUCYNTA and NUCYNTA extended release [ER]) on sex hormone concentrations in healthy male volunteers (vs placebo and morphine) and patients with osteoarthritis (vs placebo and oxycodone), and 2) present a mechanistic hypothesis explaining how the combined MOR agonist and NRI activities of tapentadol may result in less impact on androgen concentrations. Methods: Three clinical studies were conducted: study 1 (single-dose comparison study vs morphine in healthy volunteers), study 2 (single-dose-escalation study in healthy volunteers without an active comparator), and study 3 (multiple-dose study vs oxycodone in patients with osteoarthritis). Studies 1 and 2 were conducted at medical research centers in Germany and the United Kingdom; study 3 was conducted at primary and secondary care centers and medical research centers in the United States. All three studies were randomized, double blind, and placebo controlled. Concentrations of testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH; study 3 only) were evaluated at 6 and 24 hours postdose in studies 1 and 2, respectively, and at varying time points postdose in study 3. Results: In study 1, mean serum total testosterone concentrations in healthy male volunteers were similar at baseline for all treatment periods; 6 hours after dosing, mean concentrations were comparable between placebo (8.6 nmol/L) and tapentadol immediate release (IR; 43 mg, 8.8 nmol/L; 86 mg, 9.3 nmol/L), but were lower following administration of morphine IR 30 mg (5.4 nmol/L). In study 2, there were no or minimal changes in testosterone in the therapeutic dose range with tapentadol IR (75-100 mg), and there was a modest decrease that appeared to level off in the supratherapeutic range (125-175 mg); mean testosterone and LH concentrations with all doses remained within normal ranges (testosterone, 4.56-28.2 nmol/L; LH, 2.9-4.6 U/L). In study 3, the decrease in the mean [standard deviation] testosterone concentration from baseline to endpoint for male patients receiving tapentadol ER (100 mg, − 1.9 [0.71] nmol/L; 200 mg, − 2.1 [0.93] nmol/L) was numerically smaller compared to oxycodone CR (20 mg, − 2.7 [0.93] nmol/L), but higher compared to placebo ( − 0.3 [1.62] nmol/L). Conclusions: These results suggest that tapentadol, which has combined MOR and NRI activities, may have a lower impact on sex hormone concentrations than pure opioid analgesics, such as morphine or oxycodone. The data and mechanistic rationale presented herein provide a justification for conducting additional hypothesis testing studies, and are not intended to be used as a basis for clinical decision making. Future studies may help elucidate whether the observed trends are clinically significant and would translate into a reduced incidence of OPIAD.

Purpose Tapentadol extended release (ER) has demonstrated efficacy and safety for the management of moderate to severe, chronic pain in adults. This study evaluated the long-term safety and tolerability of tapentadol ER in patients with chronic osteoarthritis or low back pain. Methods Patients were enrolled in this 1-year, open-label extension study after completing one of two 15-week, placebo-controlled studies of tapentadol ER and oxycodone controlled release (CR) for osteoarthritis knee pain (NCT00421928) or low back pain (NCT00449176), a 7-week crossover study between tapentadol immediate release and tapentadol ER for low back pain (NCT00594516), or a 1-year safety study of tapentadol ER and oxycodone CR for osteoarthritis or low back pain (NCT00361504). After titrating the drug to an optimal dose, patients received tapentadol ER (100–250 mg BID) for up to 1 year (after finishing treatment in the preceding studies); patients who were previously treated with tapentadol ER in the 1-year safety study received tapentadol ER continuously for up to 2 years in total. Findings Of the 1,154 patients in the safety population, 82.7% were aged >65 years and 57.9% were female; 50.1% had mild baseline pain intensity. Mean (SD) pain intensity scores (11-point numerical rating scale) were 3.9 (2.38) at baseline (end of preceding study) and 3.7 (2.42) at end point, indicating that pain relief was maintained during the extension study. Improvements in measures of quality of life (eg, EuroQol-5 Dimension and the 36-item Short Form Health Survey [SF-36]) health status questionnaires) achieved during the preceding studies were maintained during the open-label extension study. Tapentadol ER was associated with a safety and tolerability profile comparable to that observed in the preceding studies. The most common treatment-emergent adverse events (incidence ≥10%; n=1154) were headache (13.1%), nausea (11.8%), and constipation (11.1%). Similar efficacy and tolerability results were shown for patients who received up to 2 years of tapentadol ER treatment. Implications Pain relief and improvements in quality of life achieved during the preceding studies were maintained throughout this extension study, during which tapentadol ER was well tolerated for the long-term treatment of chronic osteoarthritis or low back pain over up to 2 years of treatment. (ClinicalTrials.gov identifier: NCT00487435.)

Background and Objectives The effectiveness and tolerability of tapentadol extended release (ER), a centrally acting analgesic with μ-opioid receptor agonist and norepinephrine (noradrenaline) reuptake inhibitor activities, have been demonstrated in patients with chronic pain, including those switching directly from prior opioid therapy. The objective of the current study was to evaluate the effectiveness and safety of conversion to oral tapentadol ER (50–250 mg twice daily) from previous around-the-clock strong opioid therapy in patients with moderate to severe, chronic malignant tumor–related cancer pain that was well-controlled. Methods This randomized, open-label, phase III study, which was conducted in Japan, included a 1- to 2-week screening period (on previous opioid) and an 8-week, open-label treatment period. Eligible patients, who were taking a strong opioid analgesic and had a mean pain intensity score

This letter is intended to provide additional clarification for your readers regarding the potentially confusing issue of adverse event vs serious adverse event reporting in a recently published phase 3 study of tapentadol extended release (ER) for malignant tumor-related pain. The results of a randomized, double-blind, phase 3 study evaluating the efficacy and safety of tapentadol ER for the management of moderate-tosevere, chronic malignant tumor-related pain were published in this journal in October 2013 in our article entitled, ‘Efficacy and safety of oral tapentadol extended release in Japanese and Korean patients with moderate-to-severe, chronic malignant tumor-related pain’. According to our company’s policy and in accordance with guidance from the International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use, all treatment-emergent adverse events (TEAEs) were recorded throughout the double-blind treatment and for 3 days after the last dose of the study drug (based on the half-life of tapentadol ER), while any spontaneously reported serious AEs were recorded for up to 30 days after the last dose of the study drug. This difference in the time periods for collecting and reporting of TEAEs vs serious AEs resulted in an apparent discrepancy in the percentage of patients experiencing disease progression. The incidence of disease progression reported in Table 4 (which lists the most common [incidence 5%] TEAEs overall) was 21.4% (36/168) with tapentadol ER and 19.2% (33/172) with oxycodone controlled release (CR), while the incidence of disease progression given in the first full paragraph beneath Table 4, which was based on serious AE reporting (which included an additional 30 day reporting period after the last dose of study drug), was 23.8% (40/168) with tapentadol ER and 20.9% (36/172) with oxycodone CR.

Background: Tapentadol has demonstrated analgesic efficacy across a range of pain conditions. Objective: In a head-to-head study of up to 10 days in duration, the analgesic efficacy and tolerability of tapentadol immediate release (IR) versus oxycodone IR using a flexible dosing regimen were compared in patients with acute low back pain (LBP) and associated radicular leg pain. Study Design: Randomized (1:1), double-blind, parallel-group study (NCT00986180). Independent Ethics Committee/Institutional Review Board approval of the protocol was obtained. Setting: Ninety US outpatient treatment centers. Methods: Patients with moderate to severe, acute LBP received tapentadol IR (50, 75, or 100 mg) or oxycodone HCl IR (5, 10, or 15 mg) every 4 to 6 hours as needed for pain for up to 10 days. Patients reported current pain intensity twice daily (11-point numerical rating scale). The primary efficacy endpoint was the sum of pain intensity differences (SPID) over 120 hours for LBP. Tapentadol IR was considered non-inferior to oxycodone IR if the upper bound of the 95% confidence interval (CI) for the least-squares mean (LSM) difference in SPID120 was less than 120. Secondary efficacy endpoints included 2-, 3-, and 10-day SPID for LBP; 2-, 3-, 5-, and 10-day SPID for index leg pain; 30% and 50% responder rates; patient and clinician global impressions of change; and patient satisfaction. Results: The safety population included 645 patients, and the modified intent-to-treat population included 585 patients. In the tapentadol IR and oxycodone IR groups, respectively, 86.3% (277/321) and 82.7% (268/324) of patients completed the study. The most common reason for study withdrawal in both treatment groups was adverse events (tapentadol IR, 6.5% [21/321]; oxycodone IR, 7.1% [23/324]). The LSM (standard error) SPID120 for LBP was 264.6 (11.43) for tapentadol IR (n = 287) and 264.0 (11.22) for oxycodone IR (n = 298). The 95% CI for the LSM difference was −32.1 to 30.9; therefore, tapentadol IR was non-inferior to oxycodone IR for relief of LBP. No significant differences were observed between tapentadol IR and oxycodone IR for other SPID endpoints or for responder rates. At the end of the study, in the tapentadol IR and oxycodone IR treatment groups, respectively, approximately two-thirds of patients (66.2% vs 66.2%) and clinicians (67.9% vs 66.6%) rated patients’ overall condition as “very much improved” or “much improved,” and more than 75% of patients (79.3% vs 78.9%) were “very satisfied” or “somewhat satisfied” with their treatment. In the tapentadol IR and oxycodone IR groups, respectively, 52.3% (168/321) and 58.0% (188/324) of patients reported at least one treatment-emergent adverse event (TEAE); the most common (≥ 10%) TEAEs were vomiting (15.9% vs 24.7%), nausea (15.9% vs 20.7%), and dizziness (11.8% vs 10.5%). Vomiting (odds ratio [95% CI], 1.74 [1.17 - 2.57]) and constipation (3.43 [1.45 - 8.11]) were significantly more likely to occur in the oxycodone IR treatment group. Two (0.6%) patients in the tapentadol IR group and 3 (0.9%) patients in the oxycodone IR group experienced treatment-emergent serious adverse events. Limitations: Strict patient monitoring is generally not representative of real-world medical practice; consequently, higher incidences of TEAEs may have been reported than would be expected in a typical practice setting; it is anticipated that this bias would be similar for both treatment groups. Conclusions: This head-to-head study demonstrated that tapentadol IR had comparable analgesic efficacy and overall safety to that of oxycodone IR for the relief of moderate to severe, acute LBP and associated radicular leg pain when using flexible dosing regimens that reflect typical use in clinical practice; however, tapentadol IR demonstrated a better gastrointestinal tolerability profile, particularly for the common opioid-related TEAEs of vomiting and constipation. Clinical Trial Registration: NCT00986180 Key words: Tapentadol, oxycodone, acute low back pain, radicular leg pain, neuropathic pain, flexible dosing, radiculopathy, gastrointestinal tolerability

Objective: To evaluate via retrospective analysis the efficacy and tolerability of tapentadol extended release (ER; 100-250 mg bid) based on patient-specific factors, including baseline pain intensity, prior opioid experience, gender, and body mass index (BMI). Design: Data were pooled from three randomized, double-blind phase III studies of similar design that evaluated the efficacy and tolerability of tapentadol ER for the management of moderate to severe, chronic osteoarthritis knee pain (NCT00421928, NCT00486811) or low back pain (NCT00449176). Setting: In the original trials, patients were recruited at primary, secondary, and tertiary care centers, institutional settings, and private practices in North America, Europe, Australia, and New Zealand. Patients: Data were analyzed separately for groups of patients divided by baseline pain intensity, prior opioid experience, gender, and BMI. Interventions: Patients received twice-daily placebo, tapentadol ER (100-250 mg), or oxycodone HCl controlled release (CR; 20-50 mg) for a 3-week titration and 12-week maintenance period. Main outcome measures: Changes from baseline in average pain intensity (11-point numerical rating scale) at week 12 of the maintenance period and for the overall maintenance period. Results: Efficacy and tolerability were evaluated in 2,968 and 2,974 patients, respectively. The efficacy of tapentadol ER was shown in subpopulations divided by baseline pain intensity, prior opioid experience, gender, and BMI. Tapentadol ER was also shown to be well tolerated and associated with better gastrointestinal tolerability than oxycodone CR in the evaluated subpopulations (divided by prior opioid experience and gender). Conclusions: Results suggest that tapentadol ER (100-250 mg bid) provides similar pain relief and tolerability, regardless of baseline pain intensity, prior opioid experience, gender, or BMI.

Objective: To evaluate a composite measure for chronic pain that balances pain relief with tolerability. Design: Post hoc meta-analysis of three randomized, multicenter, double-blind studies. Participants: Subjects with moderate-to-severe chronic osteoarthritis knee pain or low back pain who had been randomized to receive active treatment with tapentadol extended release (ER; n = 978) or oxycodone controlled release (CR; n = 999). Twenty-two subjects were excluded, mainly because they did not receive treatment. Main outcome measures: We defined the composite measure as GTE 30 percent pain relief without nausea/vomiting/constipation and without discontinuations (GTE 30 percent PRT [pain relief/tolerability]). We also considered GTE 50 percent PRT as well as GTE 30 percent and GTE 50 percent pain relief without any adverse events of any type. To further evaluate GTE 30 percent PRT, we studied its relationship with four patient-reported outcomes: EQ-5D, Physical and Mental Component Summaries of SF-36, Patient Global Impression of Change, and Patient Assessment of Constipation Symptoms. Results: At week 12, tapentadol ER recipients were more likely to have GTE 30 percent PRT than oxycodone CR recipients (OR, 3.15; 95% CI, 2.47, 4.00; p < 0.001). Significant differences were also observed with the other three composite measures (p < 0.001). At week 12, subjects with GTE 30 percent PRT had more favorable changes in all patient-reported outcomes than those without and were more likely to have threshold changes in EQ-5D and SF-36 (all p < 0.001). Conclusions: Tapentadol ER was associated with significantly better composite outcomes than oxycodone CR. Because both pain relief and gastrointestinal tolerability appeared to be related to outcomes, the composite measure may represent a useful tool for comparing opioids that merits further evaluation. Keywords: chronic pain, gastrointestinal tolerability, composite measure, opioid, oxycodone, tapentadol DOI:10.5055/jom.2013.0147

Objective: To evaluate serum pharmacokinetics of tapentadol administered to healthy subjects as extended-release (ER) tablets. Design: Seven single-dose studies (five randomized, crossover, bioequivalence studies; a study in Japanese men; and a randomized, crossover, effects-of-food study) and one repeated-dose study. Setting: Clinical research settings in the United States and The Netherlands. Patients or participants: Healthy males and females were enrolled into seven studies; one study enrolled only Japanese males. Interventions: In the bioequivalence studies, subjects first received one polyethylene oxide- or hypromellose-based tapentadol ER tablet (50, 100, 150, 200, or 250 mg; one dose per study), then (after washout) the other formulation (matching dose). In all other studies, subjects received polyethylene oxide-based tapentadol ER tablets. In the repeated-dose study, subjects received one 250 mg tablet, then (after washout) one 250 mg tablet every 12 hours (five doses). In the food-effect study, subjects received one 250 mg tablet within 30 minutes after a high-fat meal or after 10 hours of fasting. In the study in Japanese men, subjects received one 100 mg tablet. Main outcome measures: Maximum tapentadol concentrations (C max ) were typically observed 5 hours after dosing. Mean terminal half-life values ranged from 4.4 to 5.9 hours. Tapentadol C max and AUC values increased proportionally following single ER (polyethylene oxide-based tablets) doses of 50 to 250 mg. Trough tapentadol concentrations increased during repeat dosing until reaching steady-state by the third dose. Serum C max and area under the concentration-time curve (AUC) values at steady state were 1.6 and 1.9 times higher relative to singledose administration. Coadministration of the 250 mg dose with a high-fat meal increased C max and AUC values by an average of < 17 percent. Conclusions: The pharmacokinetics of tapentadol ER are consistent after repeated and single-dose administration. Tapentadol ER may be administered without regard to food intake. No clinically significant differences were observed in the pharmacokinetics of tapentadol between Japanese and Caucasian subjects.

Throughout the world, in both developed and developing countries, arthritis is one of the most common causes of chronic pain (Catala et al., 2002; Elliott et al., 1999; Johannes et al., 2010; Tsang et al., 2008). The National Arthritis Data Workgroup estimates that 46.4 million adults in the United States have been diagnosed with some form of arthritis based on analyses of data from the third National Health and Nutrition Examination Survey (NHANES III; 1991-1994), the 2003 to 2005 National Health Interview Survey, and 2005 US Census Bureau population estimates (Helmick et al., 2008; Lawrence et al., 2008). Within this group, approximately 27 million adults have been diagnosed with osteoarthritis, making it the most common form of arthritis in the United States (Lawrence et al., 2008). The prevalence of osteoarthritis increases with age (Kopec et al., 2007; Lawrence et al., 2008; Sakalauskiene & Jauniskiene, 2010; Shane & Loeser, 2010). Based on data from approximately 4 million patients seen over a 1-year period in British Columbia, Canada, the estimated prevalence of osteoarthritis increases from approximately 7% in patients between 40 and 44 years of age to 26% in patients between 60 and 64 years of age and to 49% in patients between 80 and 84 years of age (Kopec et al., 2007). The prevalence of knee osteoarthritis is particularly high in the elderly, and knee osteoarthritis is a major cause of disability in elderly patients (Shane & Loeser, 2010). Based on data from NHANES III and the Framingham Osteoarthritis Study, the prevalence of knee osteoarthritis in the United States is estimated to be 14% in adults 26 years of age or older, 19% in those 45 years of age or older, 37% in those 60 years of age or older, and 44% in those over 80 years of age (Dillon et al., 2006; Felson et al., 1987; Lawrence et al., 2008). Osteoarthritis can have a negative impact on health-related quality of life and psychological well-being (Axford et al., 2008; Breedveld, 2004; de Bock et al., 1995; Jinks et al., 2007; Majani et al., 2005; Salaffi et al., 2005). Patients with osteoarthritis are often limited in their ability to participate in main daily activities (eg, household duties, employment, body care, ambulation, and sleep) and to maintain their independence (de Bock et al., 1995; Hunter et al., 2008; Jinks et al., 2007; Segal et al., 2004). Patients’ mental health has been shown to decrease progressively over time, and patients with more severe osteoarthritis pain are most likely to experience depression and to have difficulty coping with their disease (Axford et

To understand the relationship between the risk of opioid-related gastrointestinal adverse effects (AEs) and exposure to tapentadol and oxycodone as well as its active metabolite, oxymorphone, using pharmacokinetic/pharmacodynamic models. The analysis was based on a study in patients with moderate-to-severe pain following bunionectomy. Population PK modeling was conducted to estimate population PK parameters for tapentadol, oxycodone, and oxymorphone. Time to AEs was analyzed using Cox proportional-hazards models. Risk of nausea, vomiting, and constipation significantly increased with exposure to tapentadol or oxycodone/oxymorphone. However, elevated risk per drug exposure of AEs for tapentadol was ~3–4 times lower than that of oxycodone, while elevated AE risk per drug exposure of oxycodone was ~60 times lower than that for oxymorphone, consistent with reported in vitro receptor binding affinities for these compounds. Simulations show that AE incidence following administration of tapentadol IR is lower than that following oxycodone IR intake within the investigated range of analgesic noninferiority dose ratios. This PK/PD analysis supports the clinical findings of reduced nausea, vomiting and constipation reported by patients treated with tapentadol, compared to patients treated with oxycodone.

INTRODUCTIONOn the basis that “a picture is worth a thousand words,”data are often presented graphically in order to convey someof the information that they contain. Modelers use graphicalrepresentations of data for numerous purposes, two of themost important being, to inform and drive the modelingprocess and to communicate with their clients who are theend users of their models. However, it is not always clearwhich graphic should be used for a particular set of data andfor a particular purpose. As such, it is very well possible thatchoosing the wrong graph may mislead rather than enlighten,which is obviously a situation to be avoided if at all possible.Part of the difficulty lies in the fact that exploratory dataanalysis (EDA), which incorporates graphical exploration ofthe data, is perceived to be as much an art as it is a science.The artistic aspect of EDA is based on human creativity andintuition, and it is our intuition that can sometimes fail on us.One of the most intuitive graphs is one in which the dataare averaged in some way and the averages plotted. This useof averages is so intuitive that it is frequently used withoutvery much thought or consideration. It must be acknowledgedthat in many cases, this proves to be a good strategy thoughthere are occasions when it can be misleading. This paperexamines some commonly encountered situations in whichsuch graphics may be misleading. The reasons why they aremisleading are explored and explained. In addition, analternative strategy is suggested.In order to maintain the confidence of the end users in amodel, it is important that any apparent contradictionbetween the model and the graphical presentation of thedata is carefully explained. It is hoped that the followingsections will go some way in helping with that explanation.For the purposes of the following discussion, it will beassumed that the response variable (Y) is recorded on acontinuous scale. The independent variable (x)maybecontinuous or discrete.The next section describes a general approach tobuilding a mixed effects model. The following two sectionsdiscuss the use of data averages and their limitations. Analternative to data averaging is introduced in the followingsection. The data averaging and alternative methods arecompared by means of a simulated trial and a real caseexample. The paper finishes with a discussion.MIXED EFFECTS MODELWhen the data are grouped in such a way thatobservations within a group are correlated, the model needsto take account of such correlation. Longitudinal data are, ofcourse, grouped and correlated in this way because repeatedobservations on the same subject (experimental unit) arecorrelated. This correlation is due to the fact that suchobservations reflect the individual characteristics of thesubject. There are several options available for modelingcorrelated data (1), one of which is the use of a mixed effectsmodel incorporating both random and fixed effects. The useof mixed effects models is limited to situations where thecorrelation between observations within a group is positive,which is the case for many datasets. These mixed effectsmodels are widely used in pharmacometrics and will form thebasis of our discussion.Consider a situation where data were collected from nsubjects with m

Two randomized, double-blind, placebo-controlled studies in acute and chronic pain treatment, powered to assess noninferiority of the efficacy of tapentadol immediate release (IR) (50 mg, 75 mg) versus oxycodone hydrochloride (HCl) IR (10 mg), established comparable efficacy of tapentadol IR with oxycodone HCl IR, and suggested tapentadol IR's improved gastrointestinal tolerability. The impact of these equianalgesic doses of tapentadol and oxycodone HCl on bowel function and gastrointestinal tolerability was then directly assessed in the current study, using a validated bowel function diary to comprehensively assess opioid-induced constipation symptoms and outcomes.In this double-blind study, patients with end-stage joint disease were randomized to tapentadol IR (50 mg or 75 mg), oxycodone HCl IR 10 mg, or placebo. Treatment with IR formulations (14 days) was followed by treatment (28 days) with extended-release (ER) formulations of active drugs (or placebo).Oxycodone HCl IR treatment significantly decreased (P0.001) mean (SD) number of spontaneous bowel movements over the 14-day period (average per week: [6.7 (5.44)] versus tapentadol IR 50 mg [9.0 (4.04)], tapentadol IR 75 mg [8.6 (4.65)], and placebo [9.9 (5.16)]) (primary measure), confirming the tolerability findings of the earlier studies. Additionally, incidences of nausea and vomiting were significantly lower over the 14-day period (nominal P0.001) for tapentadol IR 50 and 75 mg, versus oxycodone HCl IR 10 mg. Results with ER formulations of tapentadol and oxycodone HCl over a longer treatment period were consistent with those of IR formulations.Tapentadol IR (50 mg, 75 mg) consistently demonstrated superior gastrointestinal tolerability, including for the most commonly reported events, such as nausea, vomiting, and constipation at doses that provide comparable efficacy with oxycodone HCl IR 10 mg. These findings validate and extend the tolerability findings of the two earlier studies that established comparable efficacy of these tapentadol and oxycodone HCl doses.

Validated tools to assess opioid-induced constipation (OIC) are needed. The aim of this study was to validate a Bowel Function Diary (BF-Diary) that includes patient-reported outcomes (PROs) associated with OIC.In a multicenter, observational study, opioid-naive or recently untreated (≥ 14 days) adults with nonmalignant, chronic pain who were prescribed oral opioid and usual care completed an electronic diary daily for 2 weeks. Test-retest reliability was assessed. Validity was evaluated for two composite end points--number of spontaneous bowel movements (SBM) and complete SBMs (SCBM)--and for other relevant PROs.Of 238 patients (mean age 54 years, 58% women), 63% reported constipation. The intraclass correlation coefficient for numbers of SBM and SCBM, and other BF-Diary PROs was ≥ 0.71 for all items except stool consistency. Mean (s.d.) number of SBM per week was significantly less in each week for patients with vs. without constipation (5.6 ± 4.3 and 7.3 ± 3.6, respectively over week 1, P=0.0012; similarly, P=0.0096 over week 2). Validity of individual items in the BF-Diary was supported (P0.05, stool consistency; P0.0001, all others).BF-Diary items are generally reliable and valid assessments for OIC research. Specifically, number of SBM is a valid measure for differentiating opioid-treated patients with and without constipation.

This randomized, double-blind, placebo- and positive-controlled 4-way crossover study evaluated the effects of tapentadol immediate release (IR) on the QT/QTc interval.Healthy subjects received tapentadol IR 100 mg or 150 mg, or placebo, every 6 h on Days 1 and 2, with a= 7-day washout between treatments. Moxifloxacin 400 mg was the positive control. Serial triplicate 12-lead electrocardiograms (ECGs) were performed; the Fridericia correction (QTcF) was the primary correction method. Serial blood sampling was performed for pharmacokinetic analyses.Of the 75 subjects who were randomized, 68 received at least 1 dose of study medication, and 59 completed the study. Upper limits of the 90% confidence intervals (CIs) for the difference in mean DeltaQTcF between tapentadol IR 100 or 150 mg and placebo were10 ms (non-inferiority criterion) for all time points. The lower limit of the 90% CI for mean DeltaQTcF between moxifloxacin and placebo exceeded 5 ms from 1 to 6 h after dosing, establishing assay sensitivity. No subject had a postdose QTc interval480 ms, change from baseline60 ms, or clinically relevant change in heart rate or other ECG variables. Steady-state concentrations were reached within 18 to 24 h. Common adverse events were vertigo (central nervous system (CNS) origin), headache, somnolence, nausea, vomiting, and feeling drunk.Therapeutic and supratherapeutic doses of tapentadol do not affect the QT/QTc interval.

To evaluate the efficacy and safety of tapentadol extended release (ER) for the management of moderate to severe chronic low back pain.Patients (N = 981) were randomized 1:1:1 to receive tapentadol ER 100 - 250 mg b.i.d., oxycodone HCl controlled release (CR) 20 - 50 mg b.i.d., or placebo over 15 weeks (3-week titration period, 12-week maintenance period).Efficacy was assessed as change from baseline in average pain intensity (11-point NRS) at week 12 of the maintenance period and throughout the maintenance period; last observation carried forward was used to impute missing pain scores. Adverse events (AEs) were monitored throughout the study.Tapentadol ER significantly reduced average pain intensity versus placebo at week 12 (least squares mean difference vs placebo [95% confidence interval], -0.8 [-1.22, -0.47]; p0.001) and throughout the maintenance period (-0.7 [-1.06,-0.35]; p0.001). Oxycodone CR significantly reduced average pain intensity versus placebo at week 12 (-0.9 [-1.24,-0.49]; p0.001) and throughout the maintenance period (-0.8 [-1.16,-0.46]; p0.001). Tapentadol ER was associated with a lower incidence of treatment-emergent AEs (TEAEs) than oxycodone CR. Gastrointestinal TEAEs, including constipation, nausea, and vomiting, were among the most commonly reported TEAEs (placebo, 26.3%; tapentadol ER, 43.7%; oxycodone CR, 61.9%). The odds of experiencing constipation or the composite of nausea and/or vomiting were significantly lower with tapentadol ER than with oxycodone CR (both p0.001).Tapentadol ER (100 - 250 mg b.i.d.) effectively relieved moderate to severe chronic low back pain over 15 weeks and had better gastrointestinal tolerability than oxycodone HCl CR (20 - 50 mg b.i.d.).

This pooled analysis of data from three phase 3 studies in patients with chronic osteoarthritis knee or low back pain evaluated the efficacy and tolerability of tapentadol prolonged release (PR; 100–250 mg twice daily) compared with placebo and oxycodone hydrochloride (HCl) controlled release (CR; 20–50 mg twice daily). Patients in each study were randomized to receive twice-daily doses of placebo, tapentadol PR (100–250 mg), or oxycodone HCl CR (20–50 mg) for a 12-week maintenance period, preceded by a 3-week titration period. Primary endpoints were change from baseline in average pain intensity (11-point numeric rating scale) at week 12 of the maintenance period and for the overall maintenance period using last observation carried forward for imputation of values missing after treatment discontinuation. A total of 2968 patients were evaluated for efficacy; 2974 patients were evaluated for safety. Compared with placebo, treatment with tapentadol PR or oxycodone CR resulted in significantly greater reductions in pain intensity from baseline at week 12 and for the overall maintenance period (all P