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

BACKGROUND

Few 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.

METHODS

Study 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.

RESULTS

In 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.

CONCLUSIONS

Extending BUP-XR treatment beyond 6 months sustained improvement in opioid abstinence and was well tolerated, supporting clinical benefit up to 18 months.

TRIAL REGISTRATION

NCT02357901 (study 1); NCT02510014 (study 2); NCT02896296 (study 3).

Assessment of craving in opioid use disorder: Psychometric evaluation and predictive validity of the opioid craving VAS

BACKGROUND

This work evaluated the psychometric properties of the single-item Opioid Craving Visual Analog Scale (OC-VAS) for opioid use disorder (OUD).

METHODS

Psychometric evaluation of the OC-VAS (range: 0-100 mm) was supported by Subjective Opiate Withdrawal Scale (SOWS) item 16 and total score, Clinical Opiate Withdrawal Scale (COWS) scores, and the 36-Item Short-Form Health Survey, using data from phase 3 study (NCT02357901; N = 487) participants who received randomized treatment and completed the OC-VAS at screening. Descriptive properties, test-retest reliability, construct validity, known-groups validity, and responsiveness were assessed. Interpretation of meaningful change and predictive validity were also explored.

RESULTS

Descriptive properties for the OC-VAS at screening did not provide evidence of problematic floor/ceiling effects or missingness. The test-retest reliability was established by weekly intraclass correlations >0.70. At the screening and end of the study, the strong positive correlations between OC-VAS and SOWS Total/Item 16 score and the significant OC-VAS differences among COWS severity groups supported construct validity and known-groups (discriminating ability) validity, respectively. The associations between the changes in OC-VAS and in supporting measures/opioid use from screening to the end of the study demonstrated responsiveness and the ability to detect change in clinical status. During the induction and randomization treatment periods, significant relationships were identified between OC-VAS score and subsequent opioid use.

CONCLUSIONS

This psychometric evaluation of the OC-VAS performed on a large OUD patient population provides evidence to support its use to measure the severity of opioid craving and its ability to predict opioid use.

Folate metabolism biomarkers from two randomised placebo-controlled clinical studies with paroxetine and venlafaxine

OBJECTIVES

Based on the hypothesis of a role for folate and vitamin B12 in major depressive disorders (MDD), we aimed at validating the association between folate pathway biomarkers and depression or antidepressant response in clinical trial populations.

METHODS

We investigated serum levels erythrocyte folate and serum levels of homocysteine, vitamin B12, and folate as disease and response biomarkers for MDD in two independent randomised, placebo-controlled clinical trials, where paroxetine or venlafaxine were used as active controls, for a total of 881 patients.

RESULTS

Significant but weak correlations between depression severity and biomarker levels could be detected in the paroxetine study for serum folate and vitamin B12, with no correlations for any biomarker in the venlafaxine study. Besides a weak association for erythrocyte folate in the venlafaxine study, no significant associations were observed between treatment response and pre-treatment levels of any of the biomarkers tested.

CONCLUSIONS

Notwithstanding the relatively large number of patients tested, we did not find consistent associations between folate biomarkers and MDD severity, or response to paroxetine and venlafaxine. Our results may be related to the particular study design or clinical population; however, our findings do not support the hypothesis of a dysfunction of one-carbon metabolism in MDD.

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.

Biomarkers for response in major depression: comparing paroxetine and venlafaxine from two randomised placebo-controlled clinical studies

The identification of biomarkers of response might speed drug development and set the premises to assist clinical practice in psychiatry. In this work, we evaluated a panel of peripheral biomarkers (including IL-6, IL-10, TNF-α, TNFRII, BDNF, CRP, MMP9 and PAI1) in depressed patients receiving paroxetine, venlafaxine, or placebo. Samples were obtained from two randomised placebo-controlled studies evaluating the efficacy and tolerability of a novel drug candidate, using either paroxetine or venlafaxine as active comparators. In both studies, the biomarker candidates were analysed in plasma collected at randomization and after 10 weeks of treatment with either placebo or active comparator (for a total of 106 and 108 subjects in the paroxetine and venlafaxine study, respectively). Data were obtained by multiplexing sandwich-ELISA system. Data were subjected to statistical analysis to assess their correlation with baseline severity and with response outcome. Increases in biomarker levels were correlated with reduction in depression severity for TNF-α, IL-6 IL-10 and CRP. Response to paroxetine treatment correlated with baseline IL-10, IL-6 and TNF-α levels, with the strongest signal being observed in males. In the venlafaxine study, a correlation was observed only between CRP level at randomisation and response, suggesting differences between the two active treatments and the two studies. Our investigations suggest that a combination of pro- and anti-inflammatory cytokines may predict response outcome in patients treated with paroxetine. The potential for IL-10, IL-6 and TNF-α as response biomarkers for a wider range of antidepressants warrants further investigations in clinical trials with other monoamine reuptake inhibitors.

Patient-reported outcomes in schizophrenia patients treated with once-monthly extended-release risperidone in a long-term clinical study

PURPOSE

RBP-7000 (PERSERIS™) is a once-monthly subcutaneous extended-release risperidone formulation approved by the United States Food and Drug Administration for the treatment of schizophrenia in adults. The objective of this study was to describe the long-term impact of RBP-7000 on health-related quality of life (HRQoL), subjective well-being, treatment satisfaction and medication preference in patients with schizophrenia.

PATIENTS AND METHODS

HRQoL was derived from a 52-week multicentre Phase III single-arm open-label outpatient study that assessed the safety and efficacy of RBP-7000 (120 mg) in patients with schizophrenia. HRQoL was measured using the EuroQol EQ-5D-5L and Short-Form Survey SF-36 version 2; well-being using the Subjective Well-being Under Neuroleptic Treatment - Short Version (SWN-S); satisfaction using the Medication Satisfaction Questionnaire and medication preference using the Preference of Medication questionnaire.

RESULTS

Of 482 participants at baseline, 234 remained through the end of study (EOS; week 52). Mean HRQoL and well-being scores remained stable between baseline (EQ-5D-5L index: 0.83; SF-36v2 Physical Component Score: 50; SF-36v2 Mental Component Score: 46; total SWN-S score: 89) and EOS (EQ-5D-5L index: 0.86; SF-36v2 Physical Component Score: 49; SF-36v2 Mental Component Score: 47; total SWN-S score: 90). The proportion of participants reporting satisfaction increased between week 4 (66%) and EOS (81%), with a similar trend for the preference of RBP-7000 over previous treatment (week 4: 66%; EOS: 72%). Sensitivity analyses suggested a minor effect of dropout on characterization of change over time in patient-reported outcomes (PRO) measures.

CONCLUSION

Study participants attained mean HRQoL scores near that of the general US population. Over two-thirds reported high satisfaction with and preference for RBP-7000 across the study period. Additional research is needed to confirm whether these PRO translate into improved outcomes such as adherence and ultimately fewer relapses in patients with schizophrenia.

Measuring recovery in opioid use disorder: clinical utility and psychometric properties of the Treatment Effectiveness Assessment

Purpose: The Treatment Effectiveness Assessment (TEA) is a patient-centered instrument for evaluating treatment progress and recovery from substance use disorders, including opioid use disorder (OUD). We assessed the TEA's reliability and validity and determined minimal clinically important differences (MIDs) in participants with moderate to severe OUD. Patients and methods: The TEA measures change in four single-item domains (substance use, health, lifestyle, community involvement) from treatment initiation across the duration of a treatment program. Self-reported responses range from 1 ("none or not much") to 10 ("much better") with items summed to a total score ranging from 4-40. We assessed floor and ceiling effects, internal consistency, test-retest reliability, known-groups validity (ANOVA stratified by current health status [36-Item Short Form Health Survey item 1]), convergent/divergent validity, and MIDs using data from a phase 3, open-label clinical trial of buprenorphine extended-release monthly injection for subcutaneous use (BUP-XR). Participants with OUD completed the TEA at screening and before monthly injections for up to 12 months. Results: Among 410 participants (mean age 38 years; 64% male), the mean baseline (pre-injection 1) TEA total score was 25.4 (SD 9.7), with <10% of participants at the measure floor and 10%-20% at the ceiling across domains. Internal consistency was high (Cronbach's α=0.90), with marginal test-retest reliability (intraclass correlation coefficient =0.69). Mean TEA total score consistently increased from baseline (n=410; mean 25.4 [SD 9.7]) to end of study (n=337; 35.0 [6.7]) and differentiated between current health status groups (P<0.001); it was weakly correlated with other measures of health-related quality of life/severity. MIDs ranged from 5-8 for the TEA total score across anchor- and distribution-based approaches. Conclusion: The TEA exhibited acceptable reliability and validity in a cohort of participants with moderate to severe OUD treated with BUP-XR. Given its brevity and psychometric properties, the TEA is a promising tool for use in clinical practice and research.

Efficacy and safety of a monthly buprenorphine depot injection for opioid use disorder: a multicentre, randomised, double-blind, placebo-controlled, phase 3 trial

BACKGROUND

RBP-6000, referred to as BUP-XR (extended-release buprenorphine), is a subcutaneously injected, monthly buprenorphine treatment for opioid use disorder. BUP-XR provides sustained buprenorphine plasma concentrations to block drug-liking of abused opioids over the entire monthly dosing period, while controlling withdrawal and craving symptoms. Administration of BUP-XR in a health-care setting also mitigates abuse, misuse, diversion, and unintentional exposure. We aimed to investigate the efficacy of different BUP-XR dosing regimens in participants with opioid use disorder.

METHODS

This randomised, double-blind, placebo-controlled, phase 3 trial was done at 36 treatment centres in the USA. Treatment-seeking adults aged 18-65 years who had moderate or severe opioid use disorder (as defined by the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders) entered an open-label run-in phase of up to 2 weeks' treatment with buprenorphine-naloxone sublingual film. Eligible participants were then randomly assigned (4:4:1:1) with an interactive voice/web-response system to receive BUP-XR 300 mg/300 mg (six injections of 300 mg), BUP-XR 300 mg/100 mg (two injections of 300 mg plus four injections of 100 mg), or volume-matched placebo every 28 days, and received weekly individual drug counselling. No supplemental buprenorphine was allowed. The primary efficacy endpoint was participants' percentage abstinence from opioid use, defined as the percentage of each participant's negative urine samples and self-reports of illicit opioid use from week 5 to week 24, analysed in the full analysis set. Safety was assessed in all participants who received at least one dose of BUP-XR or placebo. This study is registered with ClinicalTrials.gov, number NCT02357901.

FINDINGS

From Jan 28, 2015, to Nov 12, 2015, 1187 potential participants were screened, 665 entered run-in, and 504 received BUP-XR 300 mg/300 mg (n=201), BUP-XR 300 mg/100 mg (n=203), or placebo (n=100). Mean participants' percentage abstinence was 41·3% (SD 39·7) for BUP-XR 300 mg/300 mg and 42·7% (38·5) for 300 mg/100 mg, compared with 5·0% (17·0) for placebo (p<0·0001 for both BUP-XR regimens). No compensatory non-opioid drug use was observed during BUP-XR treatment. The most common adverse events were headache (17 [8%] participants in the BUP-XR 300 mg/300 mg group vs 19 [9%] participants in the BUP-XR 300 mg/100 mg group vs six [6%] participants in the placebo group), constipation (16 [8%] vs 19 [9%] vs 0), nausea (16 [8%] vs 18 [9%] vs five [5%]), and injection-site pruritis (19 [9%] vs 13 [6%] vs four [4%]). The BUP-XR safety profile was consistent with other buprenorphine products for treatment of opioid use disorder, except for injection-site reactions, which were reported in more than 5% of all participants who received BUP-XR, but were mostly mild and not treatment-limiting.

INTERPRETATION

Participants' percentage abstinence was significantly higher in both BUP-XR groups than in the placebo group. Treatment with BUP-XR was also well tolerated. The availability of this monthly formulation, delivered by health-care providers, represents an advance in treatment for opioid use disorder that enhances the benefits of buprenorphine by delivering sustained, optimal exposure, while reducing risks of current buprenorphine products.

FUNDING

Indivior.

Use of Longitudinal Dose-Response Modeling to Support the Efficacy and Tolerability of Alitretinoin in Severe Refractory Chronic Hand Eczema (CHE)

Longitudinal dose–response analyses of alitretinoin (an investigational agent in the US) were conducted to supplement results from phase III studies in severe, refractory chronic hand eczema, with objectives to address several outstanding development issues (e.g., optimal dose, possible factors affecting efficacy and/or tolerability). Models were fitted to the physicians' global assessment score and triglycerides over time. Five hundred trials were simulated to evaluate the relevance of findings. Analyses clarified that the optimal dose of alitretinoin was 30 mg once daily, where response rates were ∼10% over placebo at 12 weeks and increased by 5–7% over placebo for every 4 weeks thereafter, for up to 24 weeks. Elderly subjects had higher magnitudes of efficacy and an increased probability of high triglycerides. Results from analyses sufficiently addressed the development issues, thereby adding to the weight of evidence supporting the efficacy and safety of alitretinoin in the treatment of severe, refractory chronic hand eczema.