Faculty Bibliography

BACKGROUND AND AIMS/OBJECTIVE:It is unclear if findings from randomized controlled trials (RCT) of medications for opioid use disorder apply to real-world settings. We estimated the effectiveness of buprenorphine-naloxone (BUP-NX) versus extended-release naltrexone (XR-NTX) on treatment interruption in a RCT and an observational study based on real-world data. DESIGN/METHODS:Target trial emulation to harmonize the protocol and statistical analyses of X:BOT (target trial) and the observational study (observational emulation). Baseline was randomization in the target trial and medically managed opioid withdrawal (MMOW) discharge in the observational emulation. SETTINGS/METHODS:X:BOT trial and Massachusetts Public Health Data Warehouse observational data (United States). PARTICIPANTS/METHODS:The target trial included all X:BOT participants. The observational emulation trial included MMOW discharges from January 2014 to May 2016. MEASUREMENTS/METHODS:Treatment strategies were BUP-NX versus XR-NTX initiation within 28 days of baseline. The outcome was treatment interruption (earliest of treatment discontinuation, incarceration, MMOW readmission, death). We estimated the 24-week risk and risk difference. FINDINGS/RESULTS:In the target trial, 94% (269/287) and 66% (187/283) of participants randomized to BUP-NX or XR-NTX initiated their assigned treatment within 28 days, respectively. In the observational emulation, BUP-NX and XR-NTX were initiated within 28 days in 9% (5209/59 076) and 3% (1813/59 076) of MMOW discharges, respectively. The adjusted 24-week treatment interruption risks (95% confidence interval) for BUP-NX and XR-NTX were 68% (60%,77%) and 72% (60%,83%) in the target trial [risk difference, -4 percentage points (pp; -17 pp,11 pp)] and 82% (81%,83%) and 93% (92%,95%) in the observational emulation [risk difference,-11 pp (-13 pp,-10 pp)]. CONCLUSIONS:Buprenorphine-naloxone might be superior to extended-release naltrexone in real-world settings where the majority of people struggle to remain on medications for opioid use disorder. Buprenorphine-naloxone initiators had a lower risk of treatment interruption than extended-release naltrexone initiators in an observational emulation, but similar risks in a randomized controlled trial, although confidence intervals were wide. Trial participation, study size and residual confounding may explain these differences.

BACKGROUND AND AIMS/OBJECTIVE:US regulatory changes allowed for additional methadone take-home doses following COVID-19 onset. How dispensing practices changed and which factors drove variation remains unexplored. We determined daily methadone dispensing trajectories over six months before and after regulatory changes due to COVID-19 using state sequence analysis and explored correlates. DESIGN/METHODS:Retrospective chart review of electronic health records. SETTINGS/METHODS:Nine opioid treatment programs (OTPs) across nine US states. PARTICIPANTS/METHODS:Adults initiating treatment in 2019 (n = 328) vs. initiating 1 month after the COVID-19 regulatory changes of March 2020 (n = 376). MEASUREMENTS/METHODS:Type of daily methadone medication encounter (in-clinic, weekend/holiday take-home, take-home, missed dose, discontinued) based on OTP clinic; cohort (pre vs. post-COVID-19); and patient substance use, clinical and sociodemographic characteristics. FINDINGS/RESULTS:Following COVID-19 regulatory changes, allotted methadone take-home doses increased from 3.5% to 13.8% of total person-days in treatment within the first 6 months in care. Clinic site accounted for the greatest variation in methadone dispensing (6.2% and 9.5% of the variation of discrepancy between sequences pre- and post-COVID-19, respectively). People who co-use methamphetamine had a greater increase in take-homes than people who did not use methamphetamine (from 3.7% pre-pandemic to 21.2% post-pandemic vs. 3.5% to 12.5%) and higher discontinuation (average 3.6 vs. 4.7 months among people who did not use methamphetamine pre-COVID-19; average 3.3 vs. 4.6 months post-COVID-19). In the post-COVID-19 cohort, females had a higher proportion of missed doses (17.2% vs. 11.9%) than males. People experiencing houselessness had a higher proportion of missed doses (19% vs. 12.3%) and shorter stays (average 3.5 vs. 4.5 months) when compared with those with stable housing. CONCLUSION/CONCLUSIONS:Daily methadone dispensing trajectories in the US both before and following COVID-19 regulatory changes appeared to depend more on the opioid treatment programs' practices than individual patient characteristics or response to treatment.

INTRODUCTION AND BACKGROUND/BACKGROUND:The three medications approved to address OUD are effective in decreasing opioid use and morbidity and mortality; however, their utility is limited by high rates of dropout from treatment. The CTN-0100 trial will develop an evidence base for strategies to improve retention on buprenorphine and extended-release naltrexone. RESEARCH DESIGN AND METHODS/METHODS:The National Drug Abuse Treatment Clinical Trials Network (CTN) study CTN-0100, "Optimizing Retention, Duration and Discontinuation Strategies for Opioid Use Disorder Pharmacotherapy" (RDD), is a multicenter, randomized, non-blinded trial enrolling more than a thousand patients from 18 community-based substance use disorder treatment programs. Participants are adult volunteers seeking to initiate medication treatment for OUD (MOUD). Individuals choose between buprenorphine or extended-release injectable naltrexone. The trial randomizes participants choosing buprenorphine, in a 3 × 2 factorial design, to a medication condition (standard-dose sublingual buprenorphine, high-dose sublingual buprenorphine, or extended-release injectable buprenorphine) and to a behavioral condition (Medical Management or Medical Management plus a digital therapeutic (smartphone) app). Individuals choosing extended-release naltrexone are randomized only to a behavioral condition. Participants receive study medication for 74 weeks and are then followed for a further 24 weeks. The primary outcome is successful retention on MOUD at 26 weeks (six months), with 50- and 74-week retention among the secondary outcomes. DISCUSSION/CONCLUSION/CONCLUSIONS:Dropout from treatment is a major barrier to the effectiveness of MOUD. The CTN-0100 study will determine whether strategies such as high dose sublingual or extended-release buprenorphine, or an app-based behavioral intervention improve retention on MOUD. CLINICALTRIALS/RESULTS:gov Identifier: NCT04464980.

AIMS/OBJECTIVE:Cannabis use is highly prevalent in patients seeking treatment for opioid use disorder. Studies have shown mixed results on the association between cannabis use and opioid use as well as the impact of MOUD on cannabis use. The current study aims to investigate the effects of buprenorphine versus naltrexone on cannabis use outcomes in treatment seeking individuals with Opioid Use Disorder (OUD). METHODS:The current study was based on data from the CTN-0051 X:BOT trial, which compared the time to return to significant opioid use survival outcomes of two treatment seeking groups, one receiving Extended-Release Naltrexone (XR-naltrexone) (N = 283) versus another receiving Buprenorphine-Naloxone (N = 287) for OUD. A mixed-effects logistic regression model including treatment assignment (buprenorphine-naloxone vs XR-naltrexone), time, and a time by treatment interaction was run on the sample with the odds of cannabis use as the outcome, as well as two cross-lagged mediation models to explore the prospective mediation of cannabis use on opioid use outcomes (and opioid use on cannabis use outcomes) by treatment assignment during the trial. RESULTS:There was a significant effect of buprenorphine treatment on reduced cannabis use. Participants receiving buprenorphine treatment were 39 % less likely to use cannabis than those receiving naltrexone over all the timepoints (p = .0499). No significant mediation was found between treatment assignment and opioid use on cannabis use outcomes or between treatment assignment and cannabis use on opioid use outcomes in this trial. CONCLUSION/CONCLUSIONS:Participants in this trial receiving buprenorphine treatment for OUD used less cannabis than those receiving naltrexone treatment.

OBJECTIVE:A trial comparing extended-release naltrexone and sublingual buprenorphine-naloxone demonstrated higher relapse rates in individuals randomized to extended-release naltrexone. The effectiveness of treatment might vary based on patient characteristics. We hypothesized that causal machine learning would identify individualized treatment effects for each medication. METHODS:This is a secondary analysis of a multicenter randomized trial that compared the effectiveness of extended-release naltrexone versus buprenorphine-naloxone for preventing relapse of opioid misuse. Three machine learning models were derived using all trial participants with 50% randomly selected for training (n = 285) and the remaining 50% for validation. Individualized treatment effect was measured by the Qini value and c-for-benefit, with the absence of relapse denoting treatment success. Patients were grouped into quartiles by predicted individualized treatment effect to examine differences in characteristics and the observed treatment effects. RESULTS:The best-performing model had a Qini value of 4.45 (95% confidence interval, 1.02-7.83) and a c-for-benefit of 0.63 (95% confidence interval, 0.53-0.68). The quartile most likely to benefit from buprenorphine-naloxone had a 35% absolute benefit from this treatment, and at study entry, they had a high median opioid withdrawal score (P < 0.001), used cocaine on more days over the prior 30 days than other quartiles (P < 0.001), and had highest proportions with alcohol and cocaine use disorder (P ≤ 0.02). Quartile 4 individuals were predicted to be most likely to benefit from extended-release naltrexone, with the greatest proportion having heroin drug preference (P = 0.02) and all experiencing homelessness (P < 0.001). CONCLUSIONS:Causal machine learning identified differing individualized treatment effects between medications based on characteristics associated with preventing relapse.

Medications for opioid use disorder (MOUD) increase retention in care and decrease mortality during active treatment; however, information about the comparative effectiveness of different forms of MOUD is sparse. Observational comparative effectiveness studies are subject to many types of bias; a robust framework to minimize bias would improve the quality of comparative effectiveness evidence. This paper discusses the use of target trial emulation as a framework to conduct comparative effectiveness studies of MOUD with administrative data. Using examples from our planned research project comparing buprenorphine-naloxone and extended-release naltrexone with respect to the rates of MOUD discontinuation, we provide a primer on the challenges and approaches to employing target trial emulation in the study of MOUD.

IMPORTANCE/UNASSIGNED:Injectable extended-release (XR)-naltrexone is an effective treatment option for opioid use disorder (OUD), but the need to withdraw patients from opioid treatment prior to initiation is a barrier to implementation. OBJECTIVE/UNASSIGNED:To compare the effectiveness of the standard procedure (SP) with the rapid procedure (RP) for XR-naltrexone initiation. DESIGN, SETTING, AND PARTICIPANTS/UNASSIGNED:The Surmounting Withdrawal to Initiate Fast Treatment with Naltrexone study was an optimized stepped-wedge cluster randomized trial conducted at 6 community-based inpatient addiction treatment units. Units using the SP were randomly assigned at 14-week intervals to implement the RP. Participants admitted with OUD received the procedure the unit was delivering at the time of their admission. Participant recruitment took place between March 16, 2021, and July 18, 2022. The last visit was September 21, 2022. INTERVENTIONS/UNASSIGNED:Standard procedure, based on the XR-naltrexone package insert (approximately 5-day buprenorphine taper followed by a 7- to 10-day opioid-free period and RP, defined as 1 day of buprenorphine at minimum necessary dose, 1 opioid-free day, and ascending low doses of oral naltrexone and adjunctive medications (eg, clonidine, clonazepam, antiemetics) for opioid withdrawal. MAIN OUTCOMES AND MEASURES/UNASSIGNED:Receipt of XR-naltrexone injection prior to inpatient discharge (primary outcome). Secondary outcomes included opioid withdrawal scores and targeted safety events and serious adverse events. All analyses were intention-to-treat. RESULTS/UNASSIGNED:A total of 415 participants with OUD were enrolled (mean [SD] age, 33.6 [8.48] years; 205 [49.4%] identified sex as male); 54 [13.0%] individuals identified as Black, 91 [21.9%] as Hispanic, 290 [69.9%] as White, and 22 [5.3%] as multiracial. Rates of successful initiation of XR-naltrexone among the RP group (141 of 225 [62.7%]) were noninferior to those of the SP group (68 of 190 [35.8%]) (odds ratio [OR], 3.60; 95% CI, 2.12-6.10). Withdrawal did not differ significantly between conditions (proportion of days with a moderate or greater maximum Clinical Opiate Withdrawal Scale score (>12) for RP vs SP: OR, 1.25; 95% CI, 0.62-2.50). Targeted safety events (RP: 12 [5.3%]; SP: 4 [2.1%]) and serious adverse events (RP: 15 [6.7%]; SP: 3 [1.6%]) were infrequent but occurred more often with RP than SP. CONCLUSIONS AND RELEVANCE/UNASSIGNED:In this trial, the RP of XR-naltrexone initiation was noninferior to the standard approach and saved time, although it required more intensive medical management and safety monitoring. The results of this trial suggest that rapid initiation could make XR-naltrexone a more viable treatment for patients with OUD. TRIAL REGISTRATION/UNASSIGNED:ClinicalTrials.gov Identifier: NCT04762537.

INTRODUCTION AND BACKGROUND/BACKGROUND:Buprenorphine, and extended-release naltrexone, are effective in decreasing opioid use, morbidity and mortality. The available evidence suggests that these medications should be used for long term treatment; however, patients often ask how long they need to be on medication, and whether it would be safe to discontinue. There are sparse data to guide us. The CTN-0100 trial will address this gap in our knowledge by studying participants who have decided to discontinue buprenorphine and extended-release naltrexone for OUD. RESEARCH DESIGN AND METHODS/METHODS:The trial is a multicenter, randomized, non-blinded study. Participants are stable adult volunteers, on sublingual buprenorphine, extended-release buprenorphine, or extended-release naltrexone, expressing an interest in discontinuing medication. Participants on buprenorphine must be stable for at least 1 year and participants on extended-release naltrexone must be stable for at least 6 months. Participants are engaged in the study for up to 96 weeks, including a flexible taper period, and are then transitioned to follow-up within the trial. All participants are randomly assigned to the study Medical Management (MM) or to MM plus Connections (CHESS health) digital smartphone application aimed at recovery and abstinence (MMD). Sublingual Buprenorphine participants are also randomized (2 × 2 design) to a taper using either sublingual or extended-release buprenorphine. DISCUSSION/CONCLUSION/CONCLUSIONS:It is hoped that this trial will provide a rich source of data on management of patients discontinuing medication for opioid use disorder (MOUD) to inform future research and practice. The trial will shed light on which strategies are most likely to lead to long-term success (absence of relapse), and what participant characteristics distinguish those who can safely discontinue MOUD from those who remain at risk of relapse should they discontinue. CLINICALTRIALS/RESULTS:gov Identifier: NCT04464980.

BACKGROUND:Mastectomies are commonly performed and strongly associated with chronic postsurgical pain (CPSP), more specifically termed postmastectomy pain syndrome (PMPS), with 25-60% of patients reporting pain 3 months after surgery. PMPS interferes with function, recovery, and compliance with adjuvant therapy. Importantly, it is associated with chronic opioid use, as a recent study showed that 1 in 10 patients continue to use opioids at least 3 months after curative surgery. The majority of PMPS patients are women, and, over the past 10 years, women have outpaced men in the rate of growth in opioid dependence. Standard perioperative multimodal analgesia is only modestly effective in prevention of CPSP. Thus, interventions to reduce CPSP and PMPS are urgently needed. Ketamine is well known to improve pain and reduce opioid use in the acute postoperative period. Additionally, ketamine has been shown to control mood in studies of anxiety and depression. By targeting acute pain and improving mood in the perioperative period, ketamine may be able to prevent the development of CPSP. METHODS:Ketamine analgesia for long-lasting pain relief after surgery (KALPAS) is a phase 3, multicenter, randomized, placebo-controlled, double-blind trial to study the effectiveness of ketamine in reducing PMPS. The study compares continuous perioperative ketamine infusion vs single-dose ketamine in the postanesthesia care unit vs placebo for reducing PMPS. Participants are followed for 1 year after surgery. The primary outcome is pain at the surgical site at 3 months after the index surgery as assessed with the Brief Pain Inventory-short form pain severity subscale. DISCUSSION/CONCLUSIONS:This project is part of the NIH Helping to End Addiction Long-term (HEAL) Initiative, a nationwide effort to address the opioid public health crisis. This study can substantially impact perioperative pain management and can contribute significantly to combatting the opioid epidemic. TRIAL REGISTRATION/BACKGROUND:ClinicalTrials.gov NCT05037123. Registered on September 8, 2021.

IMPORTANCE/UNASSIGNED:No existing model allows clinicians to predict whether patients might return to opioid use in the early stages of treatment for opioid use disorder. OBJECTIVE/UNASSIGNED:To develop an individual-level prediction tool for risk of return to use in opioid use disorder. DESIGN, SETTING, AND PARTICIPANTS/UNASSIGNED:This decision analytical model used predictive modeling with individual-level data harmonized in June 1, 2019, to October 1, 2022, from 3 multicenter, pragmatic, randomized clinical trials of at least 12 weeks' duration within the National Institute on Drug Abuse Clinical Trials Network (CTN) performed between 2006 and 2016. The clinical trials covered a variety of treatment settings, including federally licensed treatment sites, physician practices, and inpatient treatment facilities. All 3 trials enrolled adult participants older than 18 years, with broad pragmatic inclusion and few exclusion criteria except for major medical and unstable psychiatric comorbidities. INTERVENTION/UNASSIGNED:All participants received 1 of 3 medications for opioid use disorder: methadone, buprenorphine, or extended-release naltrexone. MAIN OUTCOMES AND MEASURES/UNASSIGNED:Predictive models were developed for return to use, which was defined as 4 consecutive weeks of urine drug screen (UDS) results either missing or positive for nonprescribed opioids by week 12 of treatment. RESULTS/UNASSIGNED:The overall sample included 2199 trial participants (mean [SD] age, 35.3 [10.7] years; 728 women [33.1%] and 1471 men [66.9%]). The final model based on 4 predictors at treatment entry (heroin use days, morphine- and cocaine-positive UDS results, and heroin injection in the past 30 days) yielded an area under the receiver operating characteristic curve (AUROC) of 0.67 (95% CI, 0.62-0.71). Adding UDS in the first 3 treatment weeks improved model performance (AUROC, 0.82; 95% CI, 0.78-0.85). A simplified score (CTN-0094 OUD Return-to-Use Risk Score) provided good clinical risk stratification wherein patients with weekly opioid-negative UDS results in the 3 weeks after treatment initiation had a 13% risk of return to use compared with 85% for those with 3 weeks of opioid-positive or missing UDS results (AUROC, 0.80; 95% CI, 0.76-0.84). CONCLUSIONS AND RELEVANCE/UNASSIGNED:The prediction model described in this study may be a universal risk measure for return to opioid use by treatment week 3. Interventions to prevent return to regular use should focus on this critical early treatment period.