A Single Ascending-Dose Study of the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of the Novel Respiratory Stimulant ENA-001.

Background ENA-001 (formerly known as GAL-021) is a novel, first-in-class respiratory stimulant. Pharmacokinetic and pharmacodynamic properties, plus safety and tolerability, were assessed in a randomized, single-center study of healthy volunteers. Methodology This four-period study was designed to test continuous two-hour intravenous infusion regimens of ENA-001 at doses of 0.96, 1.44, and 1.92 mg/kg/hour versus placebo. Each participant received four infusions with a seven-day minimum washout between them: one infusion each of the three doses of ENA-001 and one placebo. Pharmacokinetic and pharmacodynamic parameters were assessed and adverse events were recorded. Results A total of 17 participants completed the study. ENA-001 was generally safe and well tolerated over the dose range studied (0.96 to 1.92 mg/kg/hour). ENA-001 was able to drive hyperventilation in a dose-dependent manner in healthy participants. Increases in ventilation due to ENA-001 were not associated with like-magnitude blood pressure response. ENA-001-stimulated decreases in ETCO2 were associated with small, statistically significant, increases in SpO2 levels. Hyperventilation occurred in two participants at the highest dose level, leading to study discontinuation. The terminal half-life of ENA-001 was 6.33 hours. Conclusions The respiratory stimulant ENA-001 demonstrated well-behaved pharmacokinetics following the two-hour infusion. Mean peak plasma concentrations and the mean total systemic exposure values were approximately dose-proportional in the dose range studied.

Use of Contrave, Naltrexone with Bupropion, Bupropion, or Naltrexone and Major Adverse Cardiovascular Events: A Systematic Literature Review.

Naltrexone/Bupropion extended release (ER; Contrave) is an extended-release, fixed-dose combination medication of naltrexone (8 mg) and bupropion (90 mg) for patients with obesity or overweight with at least one weight-related comorbidity. Obese and overweight patients with or without comorbidities are at increased cardiovascular (CV) risk. Due to the increased CV risk profile in this patient population, this systematic literature review was conducted to assess human studies reporting major adverse CV events (MACE) and other CV events. A priori eligibility criteria included clinical studies (randomized and observational) published from January 1, 2012, to September 30, 2021, with data comparing users of naltrexone/bupropion ER, naltrexone with bupropion, bupropion without naltrexone, or naltrexone without bupropion versus comparator groups (placebo or other treatments), and with sufficient information to determine the frequency of MACE or other CV adverse events by treatment group. Among 2539 English-language articles identified, 70 articles met the eligibility criteria: seven studies of naltrexone/bupropion ER or naltrexone with bupropion, 32 studies of bupropion, and 31 studies of naltrexone. No studies reported an increased risk of MACE among users of naltrexone/bupropion ER, naltrexone with bupropion, or bupropion or naltrexone individually compared with nonusers. One-half of the available studies (n = 35) reported no (zero) CV events and the other half (n = 35) reported that a non-zero frequency of CV events occurred. Four studies reported data on MACE, including three studies of bupropion and one study of naltrexone/bupropion ER. For composite MACE and its components, the difference in proportions between naltrexone/bupropion ER-, bupropion-, or naltrexone-treated patients compared with active comparators or placebo-treated patients did not exceed 2.5%. In conclusion, the available human evidence does not indicate an increased risk of CV events or MACE following use of naltrexone/bupropion ER, naltrexone with bupropion, or the individual components.

The relationship between early weight loss and weight loss maintenance with naltrexone-bupropion therapy.

Background: Extended-release (ER) naltrexone/bupropion (NB) was associated with greater weight loss than placebo in four randomized, 56-week trials. The association of NB with longer-term maintenance of weight loss remains unknown. Methods: We conducted a post-hoc analysis of four phase III, randomized, double-blind, placebo-controlled, 56-week studies (COR-I, COR-II, COR-BMOD, and COR-DM), the placebo-controlled cardiovascular outcomes trial LIGHT (208 weeks), and the randomized, open-label trial IGNITE (78 weeks). Included subjects were treated with NB 32 mg/360 mg or placebo, with baseline, week 16, and final time point data. The primary outcome was Kaplan-Meier-estimated weight loss maintenance in each study for up to 204 weeks. Findings: Our analysis included data from 10,198 particpants (NB=5412; placebo=4786). Proportions of patients with ≥5% or ≥10% weight loss maintenance were numerically higher for NB vs. placebo in all studies and time points. Differences were statistically significant for ≥5% weight loss maintenance in COR-BMOD and COR-I/-II at weeks 52 and 56 and the LIGHT study at weeks 52, 104, and 208. For ≥10% weight loss maintenance, differences were statistically significant in COR-I/COR-II at weeks 52 and 56. Interpretation: These data suggest that NB could be used as part of long-term, comprehensive weight loss and weight loss maintenance strategies. Funding: Orexigen Therapeutics, Inc. and Bausch Health Canada.

Extended-release naltrexone/bupropion is safe and effective among subjects with type 2 diabetes already taking incretin agents: a post-hoc analysis of the LIGHT trial.

BACKGROUND: Extended-release naltrexone/bupropion (NB) is indicated for chronic weight management. Incretin agents are recommended for patients with type 2 diabetes. This analysis looked at the add-on of NB to incretins to see if weight loss could occur in patients already stabilized on incretin agents. METHODS: This was a post-hoc analysis of NB vs. placebo (PL) among subjects with type 2 diabetes stable on an incretin agent prior to randomization in a double-blind, PL-controlled cardiovascular outcome trial (N = 1317). RESULTS: Over 1 year, mean weight loss was significantly greater among NB patients vs. PL among those taking DPP-4i (mean absolute difference 4.6% [p < 0.0001]) and those taking GLP-1RAs (mean absolute difference 5.2%, p < 0.0001). Proportions of subjects achieving 5% weight loss were significantly greater for NB vs. PL at weeks 26 and 52 among those taking DPP-4is or GLP-1RAs. There were no significant differences in effectiveness observed between NB + DPP-4i and NB + GLP-1RA or between PL + DPP-4i and PL + GLP-1RA in any of the analyses. Serious adverse events were reported by 9.1% and 11.1% for PL + DPP-4i and PL + GLP-1RA, respectively, and 13.3% and 12.4% of NB + DPP-4i and NB + GLP-1RA, respectively. CONCLUSION: NB appears to be effective in reducing weight in patients with T2DM and obesity/overweight who are taking DPP-4ihibitors or GLP-1RA. The SAE rates in all arms of this analysis were lower than have been reported in other cardiovascular outcome trials in type 2 diabetes.

Psychiatric Safety and Weight Loss Efficacy of Naltrexone/bupropion as Add-on to Antidepressant Therapy in Patients with Obesity or Overweight.

There is significant association between obesity and depression. Naltrexone/Bupropion (NB) is indicated for treatment of overweight and obesity (BMI ≥27 kg/m2 with a comorbidity or ≥30 kg/m2). This post-hoc analysis examines safety and efficacy of NB and placebo among individuals with overweight or obesity who were also taking antidepressant therapy during the LIGHT trial (N=8910). Subjects were divided into four subgroups: NB + antidepressants (n=1150), NB without antidepressants (n=3300), placebo + antidepressants (n=1127) and placebo without antidepressants (n=3317). Among subjects taking NB, the combined incidence of serious adverse events (AEs) and AEs leading to treatment discontinuation was not significantly different between those on antidepressants and those who were not. The key weight-loss efficacy analyses were performed on NB or placebo-treated subjects who remained on study therapy through 104 weeks and who did or did not have documented antidepressant use at each of the baseline, week 52 and week 104 visits (Completers: N=1811; 47.0% female, 86.9% white, mean age of 61 years, mean baseline BMI 37.4 kg/m2). The mean adjusted weight change in subjects taking antidepressants was numerically, but not significantly greater for NB vs. placebo (-6.3% vs. -4.3%). For those subjects not on antidepressants, weight loss was significantly greater for NB vs. PL (-6.8% vs. -3.6%). NB is generally well tolerated in patients with overweight or obesity who are on antidepressants and is effective in promoting weight loss regardless of antidepressant use. These results show that for patients on antidepressant therapy, NB may be an effective option for obesity management.

Extended-release naltrexone/bupropion and liver health: Pooled, post hoc analysis from four randomized controlled trials.

Sustained weight loss improves liver histology in non-alcoholic fatty liver disease. This post hoc analysis of four phase III, 56-week, randomized controlled trials investigated if extended-release naltrexone and bupropion (NB) affects alanine aminotransferase (ALT) and Fibrosis-4 (FIB-4) index in adults with overweight or obesity. Two thousand and seventy-three subjects (NB = 1310; placebo = 763; 79.0% female; 81.6% Caucasian) had baseline mean weight 101 kg, body mass index 36.2 kg/m2 , ALT 26.9 IU/L and FIB-4 0.79. At 56 weeks, NB-treated subjects experienced more weight loss than placebo (8.7 vs. 3.2 kg, respectively, P < .0001). Weight loss, independent of treatment, was associated with improved ALT and FIB-4 (P < .0001). There was a significant independent effect of NB on change from baseline for FIB-4 (P < .0001), but not for ALT (P = .54). Categorical ALT response (from above to within normal ranges: 10-40 IU/L for men; 7-35 IU/L for women) and achievement of 25% and 50% reduction in ALT were greater for NB versus placebo, and independently affected by weight loss (P < .0001), but not treatment. NB-associated weight loss may improve liver health by normalizing ALT values for those with high baseline levels.

Relationship between change in pain intensity and functional outcomes in patients with chronic pain receiving twice daily extended-release hydrocodone bitartrate.

OBJECTIVE: Evaluate levels of pain relief achieved in patients with chronic pain treated with hydrocodone-extended release (HC-ER) up to 48 weeks and show that these levels were associated with secondary functional and global outcomes. DESIGN: Post hoc analyses were based on a previously reported study that started with an open-label conversion/titration phase for ≤ 6 weeks followed by an openlabel 48-week treatment phase. SETTING: Private practice and institutional pain centers. PARTICIPANTS: Three hundred ninety-one opioid-experienced subjects with moderate to severe pain for ≥ 3 months. INTERVENTIONS: Individualized doses (20-300 mg) of extended-release hydrocodone every 12 hours. MAIN OUTCOME: Almost 60 percent (232/391) of subjects achieved moderate or substantial levels of pain relief (≥ 30 percent reduction in pain score) during the study. RESULTS: Subjects who achieved moderate or substantial pain relief demonstrated significant (p <0.001) improvements in Oswestry Disability Inventory (ODI), all pain interference outcomes, and Subject Global Assessment of Medication. Subjects with substantial pain relief had decreases in ODI, Hospital Anxiety and Depression Scale (HADS) anxiety, and HADS depression scores of -13.4 ± 14.92, -1.9 ± 3.37, and -1.7 ± 3.26, respectively. The five most commonly reported treatment-emergent adverse events were constipation (12.5 percent), back pain (11.1 percent), nausea (9.9 percent), vomiting (9.7 percent), and arthralgia (7.8 percent) and are consistent with opioid therapy. CONCLUSIONS: Moderate or substantial levels of pain relief were associated with the greatest functional improvements in patients treated with HC-ER. These results may help define success of opioid therapy and determine if it should be continued or an alternative treatment should be tried.

An Analysis of Rescue Medication Utilization from a 3-Month, Randomized, Double-Blind, Placebo-Controlled Study in Patients with Chronic Low Back Pain Treated with Single-Entity, Twice-Daily, Extended-Release Hydrocodone.

OBJECTIVE: To evaluate the durability of pain relief provided by a new formulation of single-entity, hydrocodone extended-release (ER) (Zohydro(®) ER) throughout the 12-hour dosing interval by examining patterns of rescue medication use. DESIGN: Phase 3, enriched enrollment, randomized withdrawal study with an open-label, conversion/titration phase (≤6 weeks) followed by a placebo-controlled, double-blind treatment phase (12 weeks). SETTING: Fifty-seven study sites in the United States enrolled patients. SUBJECTS: One hundred and fifty-one opioid-experienced subjects with moderate to severe chronic low back pain who were treated with hydrocodone ER once every 12 hours. METHODS: Post hoc analysis of rescue medication use by frequency and distribution of use following the morning and evening dose of hydrocodone ER. RESULTS: No rescue medication was used following the morning or evening dose of hydrocodone ER during 36.0% and 76.7% of the dosing days, respectively. Time distribution of rescue medication use showed that 79.3% of all rescue medication doses were administered following the morning dose, with the highest rate of usage (46.2%) occurring 4-8 hours postdose, followed by 18.7% and 14.4% usage 0-4 and 8-12 hours postdose, respectively. Examination of the three 4-hour intervals following the evening dose of hydrocodone ER revealed similar minimal rescue medication use (5.6-8.2%). CONCLUSIONS: End-of-dose failure was not observed based on the use of rescue medication after administration of single-entity, twice daily, hydrocodone ER capsules (Zohydro ER).

Review of outcomes after cessation of gonadotropin-releasing hormone agonist treatment of girls with precocious puberty.

Although gonadotropin-releasing hormone agonists (GnRHa) have been the standard of care of central precocious puberty (CPP) management for many years, there are still questions about the long-term consequences of treatment. With increased utilization of GnRHa treatment, it is now possible to assess posttreatment outcomes in the immediate posttreatment period and into adulthood. This literature review reports on the long-term effects of GnRHa therapy in girls with CPP after therapy has been discontinued. Published reports confirm the reversibility of hypothalamic-pituitary-ovarian axis suppression in females after cessation of GnRHa therapy, with the majority of patients achieving ovulatory menstrual cycles of normal timing and duration. GnRHa therapy does not appear to induce polycystic ovary syndrome or have long-term negative repercussions on either bone mineral density or body composition. Evidence is currently insufficient to identify agent-specific differences in outcomes, reproductive function, and health of offspring.

Testosterone 2% gel can normalize testosterone concentrations in men with low testosterone regardless of body mass index.

INTRODUCTION: Little is known about the effect of body mass index (BMI) on the efficacy and safety of testosterone therapy in hypogonadal men. A prior noncomparative trial demonstrated that testosterone 2% gel restored testosterone levels in hypogonadal men and was generally well tolerated. AIM: This post hoc analysis evaluated the influence of BMI on the pharmacokinetics of testosterone therapy in men with low testosterone. METHODS: Men (N = 149) aged 18-75 applied testosterone 2% gel to the front and inner thigh once daily for 90 days. Starting dose was 40 mg/day, which could be adjusted at days 14, 35, and 60. Patients were split into categories depending on baseline BMI: Tertile 1 (≤ 29.1 kg/m(2)), Tertile 2 (29.2-32.4 kg/m(2)), and Tertile 3 (>32.4 kg/m(2)). MAIN OUTCOME MEASURES: Efficacy end points were average serum total testosterone concentrations over 24 hours and maximum serum testosterone concentrations at day 90. Adverse events were recorded. RESULTS: The efficacy analysis included 129 men with low testosterone (mean age 52.9, 54.0, and 54.2 years for Tertiles 1, 2, and 3, respectively) defined as serum testosterone <250-300 ng/dL. Baseline testosterone levels were comparable across BMI tertiles. After 90 days of treatment with testosterone 2% gel (≥ 40 mg/day), 79.1%, 79.5%, and 73.8% of patients in Tertiles 1, 2, and 3, respectively, achieved serum testosterone concentrations in the physiologic range (i.e., ≥ 300 to ≤ 1,140 ng/dL). The mean average daily dose at day 90 was higher in participants in Tertiles 3 vs. 2 (P = 0.039) and Tertiles 3 vs. 1 (P = 0.010). The gel was generally well tolerated, with skin reactions the most commonly reported adverse event (16.1%; n = 24). CONCLUSIONS: In this study, daily application of testosterone 2% gel was effective at returning serum testosterone to physiologic levels in men with low testosterone and high BMI, although required dose was affected by BMI.

Random unstimulated pediatric luteinizing hormone levels are not reliable in the assessment of pubertal suppression during histrelin implant therapy.

BACKGROUND: Gonadotropin-releasing hormone agonist (GnRHa)-stimulated luteinizing hormone (LH) is the standard hormonal assessment for both diagnosis and therapeutic monitoring of children with central precocious puberty (CPP). Use of unstimulated (random) LH levels may be helpful in diagnosis and has gained popularity in monitoring GnRHa therapy despite lack of validation against stimulated values. The objective of this investigation was to assess the suitability of random LH for monitoring pubertal suppression during GnRHa treatment. METHODS: Data from a multi-year, multicenter, open-label trial of annual histrelin implants for CPP was used for our analysis. Children meeting clinical and hormonal criteria for CPP, either naïve to GnRHa therapy or previously treated with another GnRHa for at least 6 months who were being treated at academic pediatric centers were included in the study. Subjects received a single 50-mg subcutaneous histrelin implant annually until final explant at an age determined at the discretion of each investigator. Monitoring visits for physical examination and GnRHa-stimulation testing were performed at regular intervals. The main outcome measure was pubertal suppression during treatment defined by peak LH < 4 mIU/mL after GnRHa stimulation. RESULTS: During histrelin treatment, 36 children underwent a total of 308 monitoring GnRHa stimulation tests. Unstimulated and peak LH levels were positively correlated (r = 0.798), and both declined from the first to second year of treatment. Mean ± SD peak LH level during therapy was 0.62 ± 0.43 mIU/mL (range, 0.06-2.3), well below the normal prepubertal mean. Mean random LH was 0.35 ± 0.25 mIU/mL (range, 0.04-1.5), 10-fold higher than the normal prepubertal mean. The random LH levels were above the prepubertal upper threshold (<0.3 mIU/mL) in 48.4% of all tests and in 88.9% of subjects at some point during therapy. CONCLUSIONS: In contrast with GnRHa-stimulated LH, unstimulated LH values frequently fail to demonstrate suppression to prepubertal values during GnRHa therapy for CPP, despite otherwise apparent pubertal suppression, and are thus unsuitable for therapeutic monitoring. TRIAL REGISTRATION: ClinicalTrial.gov NCT00779103.

Single vs composite measures of pain intensity: relative sensitivity for detecting treatment effects.

Assay sensitivity remains a significant issue in pain clinical trials. One possible method for increasing assay sensitivity for detecting changes in pain intensity is to increase the reliability of pain intensity assessment by increasing the number of intensity ratings obtained, and combining these ratings into composite scores. The current study performed secondary analyses from a published clinical trial to test this possibility. The reliability and assay sensitivity pain intensity scores made up of 1 to 9 24-hour pain intensity recall ratings were compared. Although the reliability of the outcome measures improved as the number of items increased, this increase in reliability was not associated with an increase in assay sensitivity. A single 24-hour recall rating was about as valid (sensitive) for detecting treatment effects as composite scores made up of 2 to 9 different ratings. If this finding replicates in other pain populations, it has significant implications for the design and conduct of pain clinical trials. Specifically, it suggests the possibility that assessment burden (and associated costs and problems related to missing data) might be greatly reduced by specifying a single recall rating as the primary outcome variable. Research is needed to explore this possibility further.

The meaning of global outcome measures in pain clinical trials: more than just change in pain intensity.

OBJECTIVES: To understand the factors that contribute to patient and physician global outcome ratings and the extent to which receiving different doses of opioids or placebo might influence the importance of these factors better. METHODS: A secondary analysis was performed using data from a prospective, multicenter, double-blind placebo-controlled, and active-controlled parallel group dose-ranging study comparing the efficacy of oxymorphone extended release (ER) 20 mg (ER20, N=121); oxymorphone ER 40 mg (ER40, N=121); oxycodone controlled release 20 mg (Oxy20, N=125); and placebo (N=124) in a sample of patients with osteoarthritis. We performed 2 regression analyses to identify the predictors of pretreatment to posttreatment improvement in patient and physician global ratings of arthritis status. RESULTS: Improvement in global ratings of arthritis status was strongly associated with a decrease in pain intensity. Pretreatment to posttreatment improvement in physical and psychological functioning made independent contributions to the prediction of both criterion variables. DISCUSSION: The findings underscore the importance of change in pain intensity as a key correlate of ratings of global improvement. However, pain intensity is not the only important factor. In the current sample, improvement in both physical and psychological functioning made independent contributions to improvements in ratings of osteoarthritis status, supporting global ratings as assessing multicomponent domains. Overall, the findings suggest that when a patient or physician reports that the patient is "doing better," the patient is likely reporting less pain intensity and engaging in more physical activity and feeling better emotionally.

An open-label pharmacokinetic study of oxymorphone extended release in the presence of naltrexone in the older adult.

OBJECTIVE: The aging population generally has greater need for analgesics and is best served by having as many good therapeutic options as possible. Geriatric analgesia requires special consideration of age-associated physiologic changes that can affect drug dosing. The study of extended-release (ER) oxymorphone in older (≥ 65 years of age) versus younger (18-40 years of age) male and female volunteers was described. METHODS: In this multiple-dose, parallel-group, open-label trial, healthy volunteers received a single oral dose of 20 mg oxymorphone ER on day 1, followed by a 48-hour washout period, then two oral doses of 20 mg oxymorphone ER tablets every 12 hours from day 3 to day 8, and a single oral dose of 20 mg oxymorphone ER on day 9. Naltrexone was administered each day to the subjects. RESULTS: The elderly had significantly higher plasma levels of oxymorphone, 6-OH-oxymorphone, and oxymorphone-3-glucuronide than the younger group (1.36-fold higher area under the concentration versus time curve [AUC] and 1.45-fold higher C(max)) when they were treated with a single dose (20 mg) of oxymorphone. Steady-state AUC and C(max) also were higher in the older group. Following adjustment for body weight, AUC values for oxymorphone and its metabolites were about 40 percent higher and the mean C(max) values were 30-35 percent higher in the older group compared to the younger group. CONCLUSION: The results of the current study of an ER formulation revealed no pharmacokinetic features that would preclude dosing in the elderly. As with any drug and any age group (but particularly the elderly), oxymorphone ER should be initiated at lower doses in elderly compared to younger patients and titrated to optimal level.

Reliability and validity of individual and composite recall pain measures in patients with cancer.

OBJECTIVES: To evaluate and compare the validity and reliability of individual and composite recall pain intensity measures. DESIGN: Secondary analyses using data from a published 14-day open-label crossover clinical trial comparing two active treatments. SETTING: Multiple settings. PARTICIPANTS: Fifty-two adults with a history of chronic cancer pain. MEASURES: Recall ratings of least, worst, and average pain during the past 2 days; composite score representing recalled characteristic pain in the past 2 days; and daily diary ratings of pain intensity from which "actual" least, worst, and average pain scores were derived. RESULTS: Recall ratings of least and average pain, and a composite score representing recalled characteristic pain were accurate (differed no more than three points from "actual" scores on a 0-100 scale). Although the recall rating of worst pain significantly (P < 0.05) overestimated actual worst pain, the differences were minor (i.e., seven to eight points on a 0-100 scale). All of the recall measures demonstrated validity via their strong associations with the measures of actual pain intensity. The recall measures also demonstrated excellent test-retest stability, although the diary-derived measures tended to be more stable than the recall measures did. The composite measure of recalled characteristic pain demonstrated a high level of internal consistency (Cronbach's α = 0.90). CONCLUSIONS: Individual recall ratings and a composite score representing recalled characteristic pain intensity are reliable and valid measures of actual pain in patients with cancer. The findings support their use as outcome measures in clinical trials.

Treatment satisfaction in osteoarthritis and chronic low back pain: the role of pain, physical and emotional functioning, sleep, and adverse events.

UNLABELLED: Global ratings of treatment satisfaction and improvement can provide an opportunity for patients to aggregate multiple aspects of their treatment into a single measure of its perceived benefits and disadvantages. Although such measures have been recommended for chronic pain clinical trials, only limited data are available that address the hypothesis that they reflect multiple aspects of patients' treatment experience. Our objective was to identify the factors that make independent contributions to ratings of treatment satisfaction. We analyzed data from 5 open-label clinical trials of lidocaine patch 5% in osteoarthritis knee pain and chronic low back pain that were 2 to 12 weeks in duration. A total of 383 patients completed the Patient Global Assessment of Treatment Satisfaction scale and measures of pain, interference with physical and emotional functioning, sleep interference, and adverse events. The results of multivariate analyses indicated that improvements in measures of pain intensity, pain relief, and interference with physical functioning each made independent contributions to treatment satisfaction in both groups of patients. Improvements in interference with emotional functioning and sleep and the presence and severity of adverse events were not associated with satisfaction. PERSPECTIVE: Measures of treatment satisfaction can reflect different aspects of the patient's treatment response, including improvements in pain and physical functioning. Increased understanding of such global measures may facilitate development of clinical trial outcomes that allow patients to evaluate with minimal burden those aspects of the treatment experience they consider personally meaningful.

Long-term tolerability and effectiveness of oxymorphone extended release in patients with cancer.

OBJECTIVE: To evaluate the long-term safety, tolerability, and effectiveness of oxymorphone extended release (ER) in patients with cancer-related pain. DESIGN: Post hoc analysis of two-1-year open-label extension studies. SETTING: Multiple US cancer treatment facilities. PATIENTS: Patients with cancer pain who had participated in two short-term crossover comparator trials of oxymorphone ER: one open-label and one double-blind randomized. INTERVENTIONS: Patients who had been taking oxymorphone ER continued the dose established in the previous study. Patients who had been taking a comparator opioid were switched to an equianalgesic dose of oxymorphone ER. All patients underwent individualized oxymorphone ER dose titration to optimize effectiveness and tolerability. ASSESSMENTS: Current, average, worst, and least pain scores were normalized to a 100-point scale. Patients rated treatment on a five-point global assessment of study medication (Poor = 1 to Excellent = 5). All adverse events (AEs) were recorded. RESULTS: Of the 80 patients who entered the extension trials, 26 completed 52 weeks, 7 discontinued owing to loss of effectiveness, and 20 discontinued owing to AEs, most of which were unrelated to study drug. No significant increase in mean (standard deviation [SDD average pain intensity was observed from baseline (30.5 [19.6], 100-point scale) to final visit (35.9 [21.1], p = 0.37). The most common AEs were concomitant disease progression (28.8 percent, n=23), nausea (22.5 percent, n=18), dyspnea (16.3 percent, n=13), fatigue (16.3 percent, n=13), and edema of the lower limb (15 percent, n=12). CONCLUSIONS: In these patients with pain related to cancer, oxymorphone ER was generally well tolerated and provided stable long-term pain control.

Negligible analgesic tolerance seen with extended release oxymorphone: a post hoc analysis of open-label longitudinal data.

OBJECTIVE: To examine the development of analgesic tolerance in patients on oxymorphone extended-release (OxymER). DESIGN: Post hoc analysis of data from a previously conducted prospective 1 year multi-center open-label extension study in which patients were able to titrate as needed. PATIENTS: Sample of 153 hip and knee osteoarthritis (OA) subjects on OxymER. Primary analyses were limited to study completers (n = 62) due to the large amount of missing data for the noncompleters (n = 91). OUTCOME MEASURES: Main outcome measures included OxymER doses (pill counts) and pain intensity ratings using a visual analog scale at monthly visits. RESULTS: There were significant dose increases from weeks 1 to 2 and 2 to 6 (P < 0.05). Doses stabilized around week 6, suggesting the completion of what we defined as "titration." Both doses and pain ratings were stable when this titration phase was excluded from the analysis (P = 0.751; P = 0.056, respectively). Only 28% of the patients had any dose changes following this titration. While there was a significantly greater dose at week 52 compared with week 10 (P = 0.010), the increase in dose became insignificant after excluding four subjects who required two dose increases (P = 0.103). CONCLUSIONS: The results showed that most of the titration/dose stabilization changes occurred within the first 10 weeks. A minority (28%) of subjects required dosage increases after this (defined) titration period. Pain reports stabilized statistically after 2 weeks. The findings of this post hoc analysis suggest a lack of opioid tolerance in the majority (72%) of these OA patients who completed this study following a defined titration period on OxymER. SUMMARY: This post hoc analysis of oxymorphone ER consumption in osteoarthritis pain vs pain report showed that most dose changes occurred during an initial "titration period" as defined. Following this titration few subjects increased dose and analgesia remained stable. These findings suggest a lack of longitudinal opioid tolerance in the majority of those OA subjects who completed the trial.

Factors affecting acceptability of titrated oxymorphone extended release in chronic low back pain - an individual patient analysis.

OBJECTIVE: To evaluate the influence of age, sex, and previous opioid experience on the likelihood of successfully titrating opioid-naive and experienced patients with chronic low back pain (CLBP) to an effective and well-tolerated dose of oxymorphone extended release (ER). METHODS: Post hoc analysis of open-label titration phases of two enriched-enrollment randomized-withdrawal phase III trials in 575 adults with moderate-to-severe CLBP. Opioid-naive patients (n = 325) initiated oxymorphone ER at 10 mg/day (5 mg q12 h). Opioid-experienced patients (n = 250) initiated at a dose equianalgesic to their previous opioid and were allowed doses of 5 mg oxymorphone immediate-release rescue medication every 4-6 h, as needed. Oxymorphone ER was gradually titrated to a dose that reduced pain to or=65 years were less likely than patients aged <65 years to complete titration (45 vs. 63%; p = 0.002; 95% CI, -0.30 to -0.06) and more likely to discontinue owing to adverse events (40 vs. 15%; p < 0.001; 95% CI, 0.14-0.36). Oxycodone-experienced patients were less likely than hydrocodone-experienced patients to complete titration (46 vs. 62%, p = 0.03; 95% CI,-0.30 to -0.02). Among successfully titrated patients, pain decreased regardless of prior opioid therapy, sex, or age. CONCLUSIONS: Most patients with CLBP were titrated to an effective, generally well-tolerated oxymorphone ER dose. Older patients and those converted from oxycodone may require more gradual titration. A study limitation is that patients initiated oxymorphone ER to comply with protocol, whereas treatment failure typically motivates opioid initiation or switching in clinical practice.