Subcutaneous Buprenorphine Research Articles

Physiologic and behavioral effects of long-acting subcutaneous and transdermal buprenorphine in rats.

To investigate thermoregulation, thermal antinociception, food/kaolin intake, fecal output, and behavior following long-acting buprenorphine preparations in rats. 8 adult male rats (Rattus norvegicus) were administered long-acting SC buprenorphine (SB; 0.65 mg/kg), transdermal buprenorphine (TB; 10 mg/kg), and controls in a randomized, cross-over design. Body temperature, self-injury, sedation, food/kaolin intake, fecal output, and thermal withdrawal latencies were measured 1, 4, 8, 12, 24, 48, and 72 hours posttreatment. Data analysis was performed with mixed linear models. Self-injury was present between 1 and 12 hours and 4 and 12 hours following TB and SB, respectively; sedation was associated with TB at 12 to 24 hours. Withdrawal latencies were longer in both TB and SB groups than in the control group. Food intake decreased with time in all groups but was significantly lower 24 to 48 hours after TB and 24 to 72 hours after SB versus controls. Kaolin intake decreased from baseline 48 to 72 hours in the control group. Fecal output decreased from baseline 24 to 72 hours in all groups but was significantly lower than controls 24 hours following TB and 24 to 48 hours in SB. Body temperature increased from baseline at 1 hour, 1 to 12 hours, and 1 to 24 hours in the control, TB, and SB groups, respectively, and was significantly higher than the control group 1 to 72 hours following TB and 4 to 24 hours after SB. Transdermal buprenorphine and SB in normal rats produced antinociception, self-injurious behavior, hyperthermia, and decreased food/fecal output. Although these buprenorphine preparations may produce antinociception, untoward effects such as hyperthermia, self-injurious behavior, and reduced food intake/fecal output may be seen.

Extended-release subcutaneous buprenorphine. The 3rd therapeutic revolution

Extended-release subcutaneous buprenorphine. The 3rd therapeutic revolution

Extended-Release Injection vs Sublingual Buprenorphine for Opioid Use Disorder With Fentanyl Use

Fentanyl has exacerbated the opioid use disorder (OUD) and opioid overdose epidemic. Data on the effectiveness of medications for OUD among patients using fentanyl are limited. To assess the effectiveness of sublingual or extended-release injection formulations of buprenorphine for the treatment of OUD among patients with and without fentanyl use. Post hoc analysis of a 24-week, randomized, double-blind clinical trial conducted at 35 outpatient sites in the US from December 2015 to November 2016 of sublingual buprenorphine-naloxone vs extended-release subcutaneous injection buprenorphine (CAM2038) for patients with OUD subgrouped by presence vs absence of fentanyl or norfentanyl in urine at baseline. Study visits with urine testing occurred weekly for 12 weeks, then 6 times between weeks 13 and 24. Data were analyzed on an intention-to-treat basis from March 2022 to August 2023. Weekly and monthly subcutaneous buprenorphine vs daily sublingual buprenorphine-naloxone. Retention in treatment, percentage of urine samples negative for any opioids (missing values imputed as positive), percentage of urine samples negative for fentanyl or norfentanyl (missing values not imputed), and scores on opiate withdrawal scales and visual analog craving scales. Of 428 participants, 123 (subcutaneous buprenorphine, n = 64; sublingual buprenorphine-naloxone, n = 59; mean [SD] age, 39.1 [10.8] years; 75 men [61.0%]) had evidence of baseline fentanyl use and 305 (subcutaneous buprenorphine, n = 149; buprenorphine-naloxone, n = 156; mean [SD] age, 38.1 [11.1] years; 188 men [61.6%]) did not have evidence of baseline fentanyl use. Study completion was similar between the fentanyl-positive (60.2% [74 of 123]) and fentanyl-negative (56.7% [173 of 305]) subgroups. The mean percentage of urine samples negative for any opioid were 28.5% among those receiving subcutaneous buprenorphine and 18.8% among those receiving buprenorphine-naloxone in the fentanyl-positive subgroup (difference, 9.6%; 95% CI, -3.0% to 22.3%) and 36.7% among those receiving subcutaneous buprenorphine and 30.6% among those receiving buprenorphine-naloxone in the fentanyl-negative subgroup (difference, 6.1%; 95% CI, -1.9% to 14.1%), with significant main associations of baseline fentanyl status and treatment group. In the fentanyl-positive subgroup, the mean percentage of urine samples negative for fentanyl during the study was 74.6% among those receiving subcutaneous buprenorphine vs 61.9% among those receiving sublingual buprenorphine-naloxone (difference, 12.7%; 95% CI, 9.6%-15.9%). Opioid withdrawal and craving scores decreased rapidly after treatment initiation across all groups. In this post hoc analysis of a randomized clinical trial of sublingual vs extended-release injection buprenorphine for OUD, buprenorphine appeared to be effective among patients with baseline fentanyl use. Patients with fentanyl use had fewer opioid-negative urine samples during the trial compared with the fentanyl-negative subgroup. These findings suggest that the subcutaneous buprenorphine formulation may be more effective at reducing fentanyl use. ClinicalTrials.gov Identifier: NCT02651584.

Buprenorphine deaths confirmed by toxicology reveal a low proportion of opioid agonist treatment before death in Finland.

We studied opioid agonist treatment (OAT) status before buprenorphine-related death in Finland, where buprenorphine is the principal OAT medicine and also the most misused opioid, through a retrospective population-based study using medico-legal cause-of-death investigation and OAT patient records. The study included all death cases (N = 570) between 2018 and 2020 with a buprenorphine or norbuprenorphine finding in post-mortem toxicology and with known drug misuse history or concomitant findings of illicit drugs. Of the deceased, 10% had received OAT in the year before death. Less than 1% of individuals < 25 years had received OAT, whereas the proportion in individuals ≥ 25 years was 13% (p < 0.001). There were significantly more females and more fatal poisonings (p < 0.001) among those < 25 years than among those ≥ 25 years. OAT medication at the time of death was sublingual buprenorphine-naloxone in 74% and subcutaneous buprenorphine in 23%. Except for significantly fewer benzodiazepine findings among those receiving OAT, minimal differences were found in terms of age, gender, cause and manner of death, or concomitant substance use between the deceased in and outside of OAT. Concomitant misuse of benzodiazepines, psychostimulants, alcohol, and gabapentinoids was frequent both in and outside of OAT and likely contributed to the death. These results suggest that access to OAT especially for young people and treatment of multiple addictions should be improved. Comprehensive information from medico-legal cause-of-death investigation as a starting point, combined with subsequent ante-mortem patient records, proved to be a successful approach to shed light on the Finnish scene of buprenorphine mortality.

Rapid induction of transdermal buprenorphine to subcutaneous extended-release buprenorphine for the treatment of opioid use disorder

BackgroundBuprenorphine is an effective and safe treatment for opioid use disorder, but the requirement for moderate opioid withdrawal symptoms to emerge prior to initiation is a significant treatment barrier.Case PresentationWe report on two cases of hospitalized patients with severe, active opioid use disorder, in which we initiated treatment with transdermal buprenorphine over 48 h, followed by the administration of a single dose of sublingual buprenorphine/naloxone and then extended-release subcutaneous buprenorphine. The patients did not experience precipitated withdrawal and only had mild withdrawal symptoms.ConclusionsThis provides preliminary evidence for a rapid induction strategy that may improve tolerability, caregiver burden, and treatment retention as compared to previous induction strategies.

Rapid Metabolism of Monthly Extended-Release Buprenorphine Formulation: A Case Report

Background: Medication-assisted treatment constitutes the gold standard management for patients with opioid use disorder. Many factors can alter the response to medications, including genetic variations. In this case report, we discuss the presentation of a patient maintained on subcutaneous extended-release buprenorphine formulation who repeatedly presented objective and subjective signs of opioid withdrawal when he was switched from weekly to monthly formulation. We particularly highlight the role of metabolic pharmacogenes in this presentation. Case Presentation: Mr. Y, a 31-year-old single man, presented to our rehabilitation center seeking assistance for his polysubstance dependence, mainly opioid use disorder. As part of his multidisciplinary treatment plan, he was started on weekly extended-release buprenorphine. After maintenance for several months, he was transitioned to the monthly equivalent formulation. Since the transition, he began to develop severe withdrawal symptoms 1-2 weeks before his next due injection. This was paralleled by a noted decrease in buprenorphine level on his urine drug screening test. As soon as the patient was placed back on the weekly formulation, his symptoms resolved. Conclusion: This is a novel case highlighting the potential role of pharmacogenomics in clinical presentation and response to medications. Switching patients from weekly to monthly extendedrelease buprenorphine formulation might make rapid or ultra-rapid metabolizers at risk of earlyonset withdrawal symptoms. =In such a case, earlier provision of the injection or switching to another formulation or medication can be considered.

Buprenorphine affects the initiation and severity of interleukin-induced acute pancreatitis in mice.

Acute pancreatitis (AP) is a common disease with no targeted therapy and has varied outcomes ranging from spontaneous resolution to being lethal. Although typically painful, AP can also be painless. Various agents, including opioids, are used for pain control in AP; the risks and benefits of which are often debated. As experimental AP in mice is used to study the efficacy of potential therapies, we studied the effect of a commonly used opioid, buprenorphine, on the initiation and progression of AP. For this, we administered extended-release buprenorphine subcutaneously before inducing the previously established severe AP model that uses interleukins 12 and 18 (IL12,18) in genetically obese (ob/ob) mice and compared this to mice with AP but without the drug. Mice were monitored over 3 days, and parameters of AP induction and progression were compared. Buprenorphine significantly reduced serum amylase, lipase, pancreatic necrosis, and AP-associated fat necrosis, which is ubiquitous in obese mice and humans. Buprenorphine delayed the AP-associated reduction of carotid artery pulse distention and the development of hypothermia, hastened renal injury, and muted the early increase in respiratory rate versus IL12,18 alone. The site of buprenorphine injection appeared erythematous, inflamed, and microscopically showed thinning, loss of epidermal layers that had increased apoptosis. In summary, subcutaneous extended-release buprenorphine interfered with the induction of AP by reducing serum amylase, lipase, pancreatic and fat necrosis, the worsening of AP by delaying hypotension, hypothermia, while hastening renal injury, respiratory depression, and causing cutaneous injury at the site of injection.NEW & NOTEWORTHY Extended-release buprenorphine interferes with the initiation and progression of acute pancreatitis at multiple levels.

Buprenorphine Enhanced Taper Tolerability Evaluation Report (BETTER): A Case Series.

Discontinuing sublingual buprenorphine (SL-BUP) has been identified by some patients as a potential outcome of success for opioid use disorder treatment. The process of tapering SL-BUP can be lengthy as unpleasant opioid withdrawal symptoms limit the pace of dose adjustments. Uncontrolled withdrawal symptoms pose a risk for return to illicit opioid use and more patient-centered options for tapering SL-BUP are needed. Previous case reports have identified using extended-release subcutaneous buprenorphine (ER-BUP) to minimize withdrawal symptoms as the dose self-decreases very gradually. Ideal dosing strategies, appropriate patient characteristics, and duration of buprenorphine release with the ER-BUP injection are not well described. We present 8 cases where a single 100 mg ER-BUP injection was administered to patients experiencing intolerable withdrawal symptoms during SL-BUP taper. Patients were taking between 2 and 6 mg SL-BUP daily prior to injection. Three patients experienced mild adverse effects the day after receiving injection, all of which were taking lower SL-BUP doses (2-3 mg). In the 12 months following injection, 3 patients experienced mild, but tolerable withdrawal symptoms at variable intervals. Two patients returned to taking SL-BUP and no patients returned to illicit opioid use. Buprenorphine urine toxicology showed elimination of buprenorphine occurred after 24 weeks. Findings from these cases support current evidence-based guidance that ER-BUP tapering is better tolerated than traditional SL-BUP tapering. These patient cases and pharmacokinetic modeling of ER-BUP suggest that a target preinjection dose of 2 to 6 mg SL-BUP will minimize the risk of more severe adverse effects or withdrawal symptoms. Patients and providers should ensure that remission is well-established before initiating SL-BUP taper. A shared decision-making approach can help support patient autonomy and understanding safety risks of discontinuing SL-BUP. Future prospective studies with larger populations could further refine dosing strategies with various SL-BUP preinjection doses and newer ER-BUP formulations.

Transition from methadone to subcutaneous buprenorphine depot in patients with opioid use disorder - a case report

IntroductionOpioid dependence is a complex condition that often requires long-term treatment and care. Methadone, a synthetic full opioid agonist, and buprenorphine, a partial agonist at the opioid receptor, are most commonly used for substitution therapy of opioid dependence and typically administered orally as a liquid and sublingual tablets. Transition from methadone to sublingual buprenorphine may precipitate withdrawal and is usually performed only in patients on low dose of methadone (&lt;30-40 mg). Microdose induction is proposed as a possible solution to ease the transition to buprenorphine.ObjectivesTo present a rapid transition from methadone to sublingual buprenorphine and after that to buprenorphine depot.MethodsA case report of a patient who was switched from methadone 60 mg to sublingual buprenorphine 8 mg using microdosing and after that switched to buprenorphine depo 16 mg weekly.ResultsPatient was successfully switched to sublingual buprenorphine and after that to buprenorphine depot. The transition was complited without withdrawal simptoms.Conclusions This report supports the use of a microdose induction to initiate buprenorphine. Additionally, this approach may be significant for patients stabilized on high doses of methadone who may not be able to tolerate a traditional buprenorphine induction.Disclosure of InterestNone Declared

96-week retention in treatment with extended-release subcutaneous buprenorphine depot injections among people with opioid dependence: Extended follow-up after a single-arm trial

BackgroundThe most recent formulation of buprenorphine treatment is extended-release depot injections (BUP-XR) that are administered subcutaneously by health care professionals. This study aimed to observe treatment outcomes of BUP-XR delivered in standard practice during a 96-week follow-up period in a community setting. MethodsThis study is an extension of the CoLAB study, a prospective single-arm, multicentre, open label trial (N=100, 7 sites in Australia) among people with opioid dependence who received monthly injections of BUP-XR to evaluate the retention in treatment. Participants were followed for 96 weeks, comprising 48 weeks of the CoLAB study followed by a 48-week extension. ResultsOf 100 participants at baseline, 47 were retained on BUP-XR at 96 weeks. The median time retained on monthly depot was 90 weeks. Heroin use (adjusted OR=0.19, P=0.012) in the month prior to baseline was associated with lower odds of retention on BUP-XR. Older age at first opioid use (adjusted OR= 1.08, P=0.009) and longer duration in OAT at baseline (adjusted OR= 1.12, P=0.001) were associated with increased retention. Prevalence of past four-weeks opioid use was estimated at 4% at 96 weeks of treatment (prevalence 0.04, 95%CI: 0.00-0.11) compared to 15% at baseline. Quality of life and medication treatment satisfaction improved over time for those retained in treatment. ConclusionThis is one of the few studies to describe long term (96 week) retention in treatment with BUP-XR in a community setting. It displayed retention rates with 47% of participants completing 96 weeks of treatment with BUP-XR. Patient reported outcomes suggest improvements in client wellbeing. FundingIndivior

Pharmacokinetic-pharmacodynamic analysis of drug liking blockade by buprenorphine subcutaneous depot (CAM2038) in participants with opioid use disorder

Buprenorphine is used to treat opioid use disorder (OUD). Weekly and monthly subcutaneous long-acting buprenorphine injections (CAM2038) provide more stable buprenorphine plasma levels and reduce the treatment burden, misuse, and diversion associated with sublingual transmucosal buprenorphine formulations. To characterize the pharmacokinetic/pharmacodynamic (PK/PD) relationship, a maximum inhibition (Imax) model was developed relating CAM2038 buprenorphine plasma concentration to drug liking maximum effect (Emax) visual analog scale (VAS; bipolar) score after intramuscular hydromorphone administration. Data included time-matched observations of buprenorphine plasma concentration and drug liking Emax VAS score after hydromorphone 18 mg administration in 47 non-treatment-seeking adults with moderate to severe OUD in a phase 2 study. Analysis used non-‍linear mixed-effects modeling (NONMEM®). The final Imax model adequately described the PK/PD relationship between buprenorphine plasma concentration and drug liking Emax VAS score. Simulations showed drug liking was effectively blocked at low buprenorphine plasma concentrations (0.4 ng/mL) where the upper 95% confidence interval of the drug liking Emax VAS score was below the pre-defined 11-point complete blockade threshold. The buprenorphine plasma concentration required to achieve 90% of the maximal effect (IC90) of drug liking was 0.675 ng/mL. Interindividual variability in responses to buprenorphine was observed; some participants experienced fluctuating responses, and a few did not achieve drug liking blockade even with higher buprenorphine plasma concentrations. This affirms the need to individualize treatment and titrate doses for optimal treatment outcomes. PK/PD models were also developed for desire to use VAS and Clinical Opiate Withdrawal Scale (COWS) scores, with results aligned to those for drug liking.

What to Expect With Pregnant or Postpartum Prescribing of Extended-Release Buprenorphine (CAM2038).

Weekly and monthly CAM2038 (Brixadi®) extended-release subcutaneous buprenorphine (XR bup) has been available in Europe and Australia for several years and was approved by the Food and Drug Administration in May 2023. Little is known about the clinical experience of patients and providers using this new medication during prenatal care. Two cases of pregnant persons with opioid use disorder receiving weekly XR bup in an ongoing randomized multi-site outpatient clinical trial are presented along with a brief review of the pharmacology and literature on XR bup formulations. The cases in pregnancy illustrate how treatment with the weekly formulation is initiated including how to make dose adjustments, which may be necessary given the longer half-life; it takes 1 month to achieve steady state. Injection site pain with medication administration was time limited and managed readily. Other injection site reactions experienced included subcutaneous erythema and induration that was delayed in onset and typically mild, resolving with minimal intervention. Delivery management and breastfeeding recommendations while on weekly XR bup were not different compared to sublingual buprenorphine (SL bup). Weekly XR bup is a new treatment for opioid use disorder that may be used in the obstetric population. Obstetric and addiction medicine clinicians should be aware of this new formulation as its use is expected to increase.

Characteristics, treatment patterns and retention with extended-release subcutaneous buprenorphine for opioid use disorder: A population-based cohort study in Ontario, Canada

BackgroundUptake and retention for opioid agonist treatment (OAT) remains low. Novel extended-release formulations may improve OAT accessibility by reducing the frequency of healthcare visits. Our aim was to examine uptake, characteristics, treatment patterns and retention of individuals initiating extended-release subcutaneous buprenorphine (BUP-ER), a monthly injectable OAT. MethodsWe conducted a population-based cohort study among adults aged 18+ initiated on BUP-ER between February 3, 2020 and March 31, 2022 in Ontario, Canada. Using administrative health data, we defined continuous BUP-ER use based on repeat injections within a 56-day period and used Kaplan-Meier curves to estimate time on treatment. Among new BUP-ER recipients, we described individual and prescriber characteristics, healthcare utilization and treatment patterns. Results2366 individuals initiated BUP-ER. The median time to BUP-ER discontinuation was 183 days (interquartile range: 66–428 days) and 52.0% of individuals were co-prescribed buprenorphine/naloxone at least once throughout the period of BUP-ER receipt. Among individuals who initiated on a dose of 300mg BUP-ER and had three or more injections, 18.8% continued to receive only 300mg doses (N=276 of 1470). Furthermore, 28.6% of those whose dose was reduced to 100mg (N=341 of 1194) had a subsequent dose increase to 300mg. ConclusionsOn average, people initiating BUP-ER discontinue within the first 6 months of treatment. While BUP-ER is likely providing an important OAT option, the high occurrence of discontinuation, supplementation with buprenorphine/naloxone, and frequent dose increases suggest inadequacy of current dosing recommendations among a proportion of individuals.

Extended-release Buprenorphine Administered at Discharge in Hospitalized Persons With Opioid Use Disorder: A Case Series.

Monthly subcutaneous injectable buprenorphine (XR-Bup) is an option for treatment of opioid use disorder (OUD) that addresses some sublingual buprenorphine adherence barriers and is infrequently offered to hospitalized patients with OUD. A retrospective case series was performed for patients receiving XR-Bup upon discharge from 1 academic medical center. Demographic information, diagnoses, follow-up, and documented factors informing the selection of XR-Bup were extracted from the electronic health record. In 1 year, 37 hospitalized patients with OUD received XR-Bup at discharge. The average age was 37.6 years, and patients were primarily Medicaid insured with an injection-related infection. The most common documented factors informing the selection of XR-Bup were as follows: previous sublingual buprenorphine adherence barriers, concurrent stimulant use disorder, and patient preference. Sixty-four percent of patients scheduled for follow-up attended appointments, and 55% received a second dose of XR-Bup. Subcutaneous injectable buprenorphine is an option for OUD treatment among hospitalized patients providing 30 or more days of buprenorphine coverage in the postdischarge period.

Comparison of Systemic Extended-release Buprenorphine and Local Extended-release Bupivacaine-Meloxicam as Analgesics for Laparotomy in Mice.

Extended-release (ER) local anesthetics can be used in multi-modal analgesia or in situations in which systemic analgesics may alter animal physiology and thus introduce interpretational confounds. In this study, we compared the analgesic efficacy of an ER buprenorphine formulation with that of a synergistic combination of ER bupivacaine and meloxicam. Female and male CD1 mice were randomly assigned to receive subcutaneous buprenorphine (3.25mg/kg) preemptively, subcutaneous infiltration of bupivacaine???meloxicam (0.03mL at incision closure (bupivacaine, 35mg/kg; meloxicam, 1mg/kg), or saline (10mL/kg SC) after induction of anesthesia. After laparotomy, mice were assessed for changes in daily body weight, rearing frequency, nest consolidation scores, time-to-integrate-nest test (TINT), and response to von Frey testing at 4, 8, 24, 48, and 72h after surgery. Daily weight, nest consolidation scores and rearing frequency were not significantly different among the 3 groups. TINT had fallen significantly response at 24 and 48h after injection in the ER buprenorphine group as compared with the saline and ER bupivacaine-meloxicam groups. Nociceptive thresholds, as assessed with von Frey testing, differed between saline controls and both analgesic groups at 4, 8, 24, 48, and 72 h after surgery. None of the mice in the bupivacaine???meloxicam group developed signs of neurotoxicity, a potential side effect of high-dose local anesthetics. This study demonstrates that local ER bupivacaine???meloxicam may be a useful alternative to systemic, ER buprenorphine for the relief of pain after laparotomy in mice.

18-Month efficacy and safety analysis of monthly subcutaneous buprenorphine injection for opioid use disorder: Integrated analysis of phase 3 studies

BackgroundFew studies investigate the natural history of patients on long-term treatment for opioid use disorder (OUD). We evaluated the long-term efficacy, safety, and tolerability experience of monthly extended-release buprenorphine (BUP-XR) in participants seeking treatment for OUD, via integrated analysis of phase 3 studies. MethodsStudy 1 was a 24-week randomized, double-blind, placebo-controlled trial of participants receiving monthly injections of BUP-XR (300 mg × 2, 100 mg × 4 [n = 203] or 300 mg × 6 [n = 201]) or placebo (n = 100). Study 2 was a 48-week, open-label trial enrolling 257 participants who completed study 1 and 412 de novo participants, to receive 6 and 12 BUP-XR injections, respectively. Study 3 was a 24-week, open-label extension enrolling 208 participants who completed study 2 for 6 additional injections. We assessed opioid abstinence as the proportion of urine opioid negative participants by visit and the percentage of each participant's negative opioid assessments during the first 6 months. ResultsIn total, 916 participants were treated with BUP-XR or placebo. By the end of 18 months, 92.7 % of the de novo cohort and 81.8 % of the study 1 cohort were urine negative for opioids. Among early nonresponders (percentage of abstinence ≤20 %), 73.1 % were urine negative after 18 months. The longer treatment period was well tolerated, with no new safety concerns, and a low incidence of opioid withdrawal signs and symptoms, and hepatic disorder. ConclusionsExtending BUP-XR treatment beyond 6 months sustained improvement in opioid abstinence and was well tolerated, supporting clinical benefit up to 18 months. Trial registrationNCT02357901 (study 1); NCT02510014 (study 2); NCT02896296 (study 3).

Population Pharmacokinetic Analysis Supports Initiation Treatment and Bridging from Sublingual Buprenorphine to Subcutaneous Administration of a Buprenorphine Depot (CAM2038) in the Treatment of Opioid Use Disorder.

In treating opioid use disorder (OUD), subcutaneous (SC) extended-release buprenorphine (BPN) depots, e.g.,CAM2038, have been shown to provide smaller and less frequent fluctuations in BPN plasma concentrations and pharmacodynamic responses, improve outcomes, reduce treatment burden, and lower risks of misuse and diversion compared to daily sublingual (SL) BPN. This analysis characterized the pharmacokinetics (PK) of BPN following intravenous and SL administration, and administration of SC CAM2038 weekly and monthly. Pharmacokinetic data from two Phase 1 and two Phase 2 trials in healthy participants and participants with OUD, respectively, were used to develop a population PK model using non-linear mixed effects modelling. The analysis included data from 252 participants and 10,658 BPN observations. The disposition of BPN was best described by a three-compartment model with first-order elimination, and absorption of SL BPN and SC CAM2038 weekly and monthly by dual parallel absorption pathways. Model diagnostics indicated good predictive performance of BPN concentrations. Buprenorphine plasma concentration-time profiles were simulated for treatment initiation, switching from SL BPN to CAM2038 weekly and monthly, and tapering after interrupting treatment with CAM2038. Simulations predicted CAM2038 weekly and monthly doses that provided BPN plasma maximum concentration (Cmax) and trough concentration (Ctrough) values at steady state within those observed following SL BPN administration. This population PK model supports the use of CAM2038 doses as individualized treatment for OUD across different treatment stages, including initiation, switching from SL BPN according to established dose conversion schedules, and tapering. ISRCTN41550730 (05/19/2014), ISRCTN24987553 (07/29/2014), NCT02611752 (11/23/2015), NCT02710526 (03/16/2016).

The switching process from buprenorphine sublingual tablets to the monthly buprenorphine subcutaneous depot injection in opioid dependent patients.

The 2018 European Union (EU) approved weekly and monthly subcutaneous buprenorphine depot injection (BUP-XR), for opioid substitution medication proved to offer some specific treatment benefits. The present study examines the process of switching from buprenorphine sublingual tablets (BUP-SL) to BUP-XR from a patient's point of view. In total, nine patients were surveyed by means of an open-answer questionnaire regarding course and side effects of the medication switch. Six of these patients were surveyed in more detail under BUP-SL, as well as 4 and 16 weeks after the switch to BUP-XR by means of a test battery of questions on socio-demography, withdrawal symptoms, craving, physical well-being, treatment satisfaction and concomitant use of illegal substances. Patients reported significant worse physical well-being and lower treatment satisfaction in 4weeks compared with 16 weeks after the medication switch to the BUP-XR. Furthermore, they reported significant more frequent co-use of illicit drugs, worse physical well-being, lower treatment satisfaction and more craving experience 4weeks after the switch compared with the treatment under BUP-SL. Patients 16 weeks under BUP-XR reported significant more illicit co-use and lower treatment satisfaction compared with patients under BUP-SL. Connections between therapy dissatisfaction, physical discomfort, experienced craving and drug co-consumption were discovered. In the first weeks after the medication switch, patients experience potentially distressing symptoms, which, however, seem to diminish over time. Close supervision and comprehensive patient education on possible burdens of the medication switch to the BUP-XR might prevent unfavourable treatment courses and premature therapy dropouts.

Industry update, December 2022.

Industry update, December 2022.

Depot buprenorphine as an opioid agonist therapy in New South Wales correctional centres: a costing model

BackgroundIn 2019 daily liquid methadone and sublingual buprenorphine-naloxone were primary opioid agonist treatments for correctional centres in New South Wales, Australia. However, both had significant potential for diversion to other patients, and their daily administration was resource intensive. An alternative treatment in the form of subcutaneous depot buprenorphine became a viable option following a safety trial in 2020 – the UNLOC-T study. Depot preparation demonstrated advantages over current treatments as more difficult to divert and requiring fewer administrations. This paper reports the results of economic modelling of staffing costs in medication administration comparing depot buprenorphine, methadone, and sublingual buprenorphine provision in UNLOC-T trial facilities.MethodsThe costing study adopted a micro-costing approach involving the synthesis of cost data from the UNLOC-T clinical trial as well as data collected from Justice Health and Forensic Mental Health Network records. Labour and materials data were collected during site observations and interviews. Costs were calculated from two payer perspectives: a) the New South Wales (state) government which funds custodial and health services; and b) the Australian Commonwealth government, which pays for medications. The analysis compared the monthly-per-patient cost for each of the three medications in trial-site facilities during July 2019. This was followed by simulation of depot buprenorphine implementation across the study population. Costs associated with medical assessment and reviews were excluded.ResultsThe monthly-per-patient New South Wales government service costs of depot buprenorphine, methadone and sublingual buprenorphine were: $151, $379 and $1,529 respectively while Commonwealth government medication costs were $434, $80 and $525. The implementation simulation found that service costs of depot buprenorphine declined as patients transitioned from weekly to monthly administration. Costs of treatment using the other medications increased as patient numbers decreased alongside fixed costs. At 12 months, monthly-per-patient service costs for depot buprenorphine, methadone and sublingual buprenorphine—which would be completely phased out by month 13—were $92, $530 and $2,162 respectively.ConclusionsDepot buprenorphine was consistently the least costly of the treatment options. Future modelling could allow for dynamic patient populations and downstream impacts for participants and the state health system.Trial registrationACTRN12618000942257. Registered 4 June 2018.