Safety of a Rapidly Dissolving Buprenorphine/Naloxone Sublingual Tablet (BNX-RDT) for Treatment of Opioid Dependence: A Multicenter, Open-label Extension Study

Buprenorphine Program Evaluation in a Private Psychiatric Office-Based Practice

PURPOSE

The opioid crisis has contributed to the mortality, morbidity, and rising healthcare costs in the United States. Buprenorphine (BUP) is an effective medication for opioid use disorder. The aims of this quality assurance evaluation of a BUP program were to (a) evaluate the clinic's performance in illicit opioid abstinence and (b) identify patient risk and resilience characteristics to improve patient success in recovery with BUP.

METHODS

A retrospective chart review of open (n = 35) and closed (n = 21) cases and a cross-sectional survey in open cases were completed. Adults (aged ≥18 years) who completed 6 months of BUP treatment at a psychiatric clinic were included. Clinical performance was measured with percentages of opioid-negative urine and completed monthly urine drug tests (UDTs) for the first 6 months. Open cases were surveyed regarding risk and resilience characteristics (frequency of opioid cravings and triggers, therapy participation, and coping skills). Descriptive statistics, t test, and chi-square test were used to analyze data.

RESULTS

Average opioid-negative urine was significantly higher in open cases than closed cases (88.57% vs. 74.82%; t = 2.885, p = .004). There was no significant association between open cases (61.4%) and closed cases (73.8%) in completed monthly UDT. Opening and closing of cases stabilized with mandatory monthly UDT. Most individuals reported therapy participation, minimal opioid cravings, and use of distraction to cope with chronic-pain-induced cravings.

CONCLUSIONS/IMPLICATIONS

This clinic met benchmarks leading to improved substance recovery. Recommendations include regular evaluations of UDT, cravings, and chronic pain; therapy participation; and continuous quality assurance activities.

Oromucosal products - Market landscape and innovative technologies: A review

Strategies that rely on oral mucosal administration have increased in the last decade and oromucosal products are paving the way to overcome specific challenges, namely improving drug bioavailability when compared with the conventional oral route, due to a reduction of the hepatic first-pass metabolism and pre-systemic degradation. Overall, the advantages of these products make oromucosal route of administration attractive for the development of value-added medicines, which can address more properly the unmet medical needs of specific patients. Generally, such products have an easy and convenient administration since they do not require water for ingestion, which may be particularly relevant for geriatric and pediatric groups, or non-cooperative patients. Usually, the development of these products aims to provide a faster onset of action, critical for acute or emergency treatments. Although oriented to achieve better therapeutic outcomes, today's drug development is primarily focused on patient-centered care, meaning that patients' specific characteristics/needs are an important driving force behind product-development efforts. In accordance, pharmaceutical innovation can rely not only on new drug substances but also on re-formulation of already approved ones or alternative routes of administration, enhancing patient convenience, treatment efficacy and/or safety. Throughout this review, the oromucosal drug products, approved in the last decade, and a retrospective analysis of their critical quality attributes and specifications will be described. Furthermore, trends and opportunities of the latest technologies in this field, as well as the number of ongoing clinical studies, will be presented and discussed.

Endogenous opiates and behavior: 2017

This paper is the fortieth consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2017 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).

Pharmacokinetics of Sublingual Buprenorphine Tablets Following Single and Multiple Doses in Chinese Participants With and Without Opioid Use Disorder

Background

Two phase I studies assessed the pharmacokinetics of buprenorphine, its metabolite norbuprenorphine, and naloxone following administration of buprenorphine/naloxone sublingual tablets in Chinese participants.

Methods

In the first phase I, open-label, single ascending-dose (SAD) study, 82 opioid-naïve volunteers received a single buprenorphine/naloxone dose ranging from 2 mg/0.5 mg to 24 mg/6 mg while under naltrexone block. In a second phase I, open-label, multiple ascending-dose (MAD) study, 27 patients with opioid dependence in withdrawal received buprenorphine/naloxone doses of either 16 mg/4 mg or 24 mg/6 mg for 9 consecutive days. Serial blood samples were collected after a single dose (SAD study) and at steady-state (MAD study). Pharmacokinetic parameters were calculated using non-compartmental analysis. Safety assessments included adverse events monitoring and laboratory tests.

Results

The pharmacokinetic profiles of buprenorphine and naloxone were consistent between single- and multiple-dose studies. Peak plasma concentrations (C_max) were reached early for buprenorphine (0.75–1.0 h) and naloxone (0.5 h), supporting rapid absorption. In the SAD study, increases in plasma exposures to buprenorphine and naloxone were less than dose proportional, in line with previous observations in Western populations. Buprenorphine-to-naloxone ratios for C_max and area under the curve (AUC) were constant over the dose range investigated and also consistent with Western populations data. Steady state was reached within 7 days of daily dosing, with slight accumulation over repeated doses. No serious adverse events were observed.

Conclusions

The present data suggest that buprenorphine/naloxone pharmacokinetic profiles in Chinese participants are consistent, overall, with those in Western populations, supporting no differences in dosing.

Clinical Trial Registration

The protocols were registered on the official website of the China Food and Drug Administration (CFDA): http://www.chinadrugtrials.org.cn/; Registration numbers CTR20132963 (RB-CN-10-0012), CTR20140153 (RB-CN-10-0015).

Electronic supplementary material

The online version of this article (10.1007/s40268-019-0277-9) contains supplementary material, which is available to authorized users.

Long-term safety of a weekly and monthly subcutaneous buprenorphine depot (CAM2038) in the treatment of adult out-patients with opioid use disorder

AIMS

To assess the long-term safety of subcutaneous buprenorphine (CAM2038) weekly and monthly depots.

DESIGN

Phase 3, open-label, observational, multi-centre 48-week trial (ClinicalTrials.gov NCT02672111).

SETTING

Twenty-six out-patient sites (United States, United Kingdom, Hungary, Denmark, Sweden, Germany, Australia) between 14 December 2015 and 12 April 2017.

PARTICIPANTS

Two hundred and twenty-eight adults with opioid use disorder; 227 received CAM2038 (37 initiated onto CAM2038 and 190 converted from sublingual buprenorphine).

INTERVENTIONS

CAM2038 weekly (8, 16, 24 or 32 mg) or monthly (64, 96, 128 or 160 mg) with flexible dosing and individualized titration utilizing multiple CAM2038 weekly and monthly doses.

MEASUREMENTS

Safety variables, urine toxicology samples and self-reported illicit opioid use were collected at each visit. Participants were administered a patient satisfaction survey at months 6 and 12, completed by 162 of 227 (71.4%) participants.

FINDINGS

The study treatment period was completed by 167 of 227 (73.6%) participants. At least one treatment-emergent adverse event (TEAE) was reported by 143 of 227 (63.0%) participants, of whom 60 of 227 (26.4%) reported as being drug-related. Most of the TEAEs, reported by 128 of 227 (56.4%) of participants, were mild or moderate in intensity. Injection-site reactions were reported by 46 of 227 (20.3%) participants, with most [45 of 46 (97.8%)] reported as mild to moderate. Five participants (2.2%) discontinued the study drug due to a TEAE, two cases (0.9%) of which were injection-site-related. No serious adverse events were attributed to the study drug. Among those remaining in the study, the percentage of opioid-negative urine tests combined with self-reports was 63.0% (17 of 27) in new-to-treatment participants and 82.8% (111 of 134) for those converted from sublingual buprenorphine. Participants reported high levels of satisfaction with CAM2038.

CONCLUSIONS

Subcutaneous buprenorphine delivered weekly or monthly (CAM2038) was well tolerated, with a systemic safety profile consistent with the known profile of sublingual buprenorphine. CAM2038 weekly and monthly was associated with high retention rates and low levels of illicit opioid use throughout this study.

Treatment of opioid dependence with buprenorphine/naloxone sublingual tablets: A phase 3 randomized, double-blind, placebo-controlled trial

INTRODUCTION

The purpose of the study is to evaluate the efficacy and safety of buprenorphine/naloxone sublingual tablets for the treatment of opioid dependence in Chinese adults.

METHODS

This multicenter, double-blind, placebo-controlled study included four periods: induction (3-5 days), stabilization (7-21 days), randomization/treatment (6 weeks), and postmedication follow-up (1 week). A total of 442 participants with opioid dependence were enrolled; 260 were randomized to buprenorphine/naloxone or placebo. The primary outcome was retention in treatment, defined as the time from randomization to treatment completion or treatment failure. Secondary outcomes included maximum consecutive days of abstinence from opioids, self-reported craving and opioid withdrawal symptoms, and urine drug screen results. Safety assessments included adverse event reporting, electrocardiograms, clinical laboratory tests, vital signs, and prior/concomitant medications.

RESULTS

The median treatment retention time (95% confidence internal) with buprenorphine/naloxone was 32 days (26-38) versus 6 days (5-8) for placebo, with a Cox hazard ratio of 0.28 (95% confidence interval, 0.21-0.38; P < 0.0001). The median maximum consecutive days of abstinence (95% confidence interval) was: buprenorphine/naloxone, 21 days (26-38); placebo, 5 days (5-8) with a Cox hazard ratio of 0.38 (95% confidence interval, 0.25-0.60; P < 0.0001). Withdrawal and craving symptoms were significantly milder with buprenorphine/naloxone versus placebo (P < 0.001). Urine drug screen results indicated significantly lower opioid usage in the buprenorphine/naloxone group compared with placebo (P < 0.001). The most commonly reported adverse events in the buprenorphine/naloxone group during treatment were aspartate aminotransferase increased and nasopharyngitis.

DISCUSSION

Efficacy and safety results from this clinical trial support a positive benefit-risk ratio for buprenorphine/naloxone sublingual tablet use in the treatment of an opioid-dependent Chinese population.

Buprenorphine/Naloxone (Zubsolv®): A Review in Opioid Dependence

A new sublingual buprenorphine/naloxone tablet (hereafter referred to as buprenorphine/naloxone; Zubsolv^®), combining a long-acting partial µ receptor agonist and an opioid antagonist, is approved for the treatment of opioid dependence in adults and adolescents aged > 15 years. This formulation has a higher bioavailability, better taste and faster sublingual dissolve time than a reference sublingual buprenorphine/naloxone tablet (Suboxone^®), advantages that provide greater patient preference (potentially improving adherence) and importantly may reduce the risk of buprenorphine parenteral abuse by providing similar buprenorphine exposure at an ≈ 30% lower dosage than reference buprenorphine/naloxone. In large phase III trials of up to 28 days, buprenorphine/naloxone was associated with high treatment retention rates during the induction and stabilization phases, and also reduced opioid craving and opioid withdrawal symptoms. Although noninferiority of buprenorphine/naloxone to sublingual buprenorphine tablet during the 2-day induction phase was only shown in one of the two similarly designed trials, pooled analyses confirmed that treatment retention rates were similar in the buprenorphine/naloxone and buprenorphine groups. Where evaluated, noninferiority of buprenorphine/naloxone to sublingual buprenorphine/naloxone film (only approved in the USA) was also demonstrated at 15 days in the stabilization phase. During the 24-week extension study, buprenorphine/naloxone maintenance therapy sustained improvements in opioid craving and addiction severity scores. Buprenorphine/naloxone was generally well tolerated, displaying a tolerability profile that was generally consistent with that seen with reference buprenorphine/naloxone. In conclusion, with potentially greater patient preference and a lower potential for parenteral buprenorphine abuse than reference buprenorphine/naloxone, buprenorphine/naloxone expands the treatment options available for adults and adolescent (aged > 15 years) patients with opioid dependence.

Pharmacokinetic and pharmaceutical properties of a novel buprenorphine/naloxone sublingual tablet for opioid substitution therapy versus conventional buprenorphine/naloxone sublingual tablet in healthy volunteers

PURPOSE

A novel sublingual buprenorphine/naloxone rapidly-dissolving tablet (BNX-RDT) for opioid substitution therapy has been developed for improved bioavailability, rapid disintegration and improved taste masking. We compared the bioavailability and pharmaceutical properties of BNX-RDT with conventional buprenorphine/naloxone sublingual tablets (BNX).

METHODS

Fasting, open-label, randomized, single-dose, two-cohort crossover study in healthy volunteers under naltrexone block. Cohort 1 (high-dose, N = 64) received BNX-RDT 11.4/2.9 mg and BNX 16/4 mg. Cohort 2 (low-dose, N = 61) received BNX-RDT 2.9/0.71 mg and BNX 4/1 mg. Plasma samples were collected over 72 h. Relative systemic exposures of buprenorphine and naloxone were assessed using standard statistical models for bioequivalence analysis. Pharmaceutical assessments included dissolve time, taste and mouthfeel assessments, and overall preference.

RESULTS

BNX-RDT 11.4/2.9 mg provided equivalent buprenorphine and naloxone exposure to BNX 16/4 mg. BNX-RDT 2.9/0.71 mg provided ~20% lower buprenorphine and 35% lower naloxone exposure compared with BNX 4/1 mg. The comparison of BNX-RDT 2.9/0.71 mg with BNX 4/1 mg did not fully meet equivalence criteria. BNX-RDT was associated with improved dose proportionality across strengths compared with BNX (post hoc analysis), resulting in lower exposure from BNX-RDT relative to BNX at the lower strength. Median perceived dissolve times were significantly shorter for BNX-RDT than BNX at high (8.5 versus 16.2 min) and low (7.6 versus 9.1 min) doses. Taste and mouthfeel were rated significantly more pleasant than BNX, with ~78% of subjects preferring BNX-RDT.

CONCLUSION

BNX-RDT provided improved buprenorphine absorption compared to a conventional sublingual tablet, with shorter dissolve times and improved taste and mouthfeel, resulting in a high preference for the novel formulation.