A controlled trial of daily versus thrice-weekly buprenorphine administration for the treatment of opioid dependence

Salivary Therapeutic Monitoring of Buprenorphine in Neonates After Maternal Sublingual Dosing Guided by Physiologically Based Pharmacokinetic Modeling

BACKGROUND

Opioid use disorder (OUD) during pregnancy is associated with high mortality rates and neonatal opioid withdrawal syndrome (NOWS). Buprenorphine, an opioid, is used to treat OUD and NOWS. Buprenorphine active metabolite (norbuprenorphine) can cross the placenta and cause neonatal respiratory depression (EC 50 = 35 ng/mL) at high brain extracellular fluid (bECF) levels. Neonatal therapeutic drug monitoring using saliva decreases the likelihood of distress and infections associated with frequent blood sampling.

METHODS

An adult physiologically based pharmacokinetic model for buprenorphine and norbuprenorphine after intravenous and sublingual administration was constructed, vetted, and scaled to newborn and pregnant populations. The pregnancy model predicted that buprenorphine and norbuprenorphine doses would be transplacentally transferred to the newborns. The newborn physiologically based pharmacokinetic model was used to estimate the buprenorphine and norbuprenorphine levels in newborn plasma, bECF, and saliva after these doses.

RESULTS

After maternal sublingual administration of buprenorphine (4 mg/d), the estimated plasma concentrations of buprenorphine and norbuprenorphine in newborns exceeded the toxicity thresholds for 8 and 24 hours, respectively. However, the norbuprenorphine bECF levels were lower than the respiratory depression threshold. Furthermore, the salivary buprenorphine threshold levels in newborns for buprenorphine analgesia, norbuprenorphine analgesia, and norbuprenorphine hypoventilation were observed to be 22, 2, and 162 ng/mL.

CONCLUSIONS

Using neonatal saliva for buprenorphine therapeutic drug monitoring can facilitate newborn safety during the maternal treatment of OUD using sublingual buprenorphine. Nevertheless, the suitability of using adult values of respiratory depression EC 50 for newborns must be confirmed.

Bupenorphine in Wisconsin Drivers: Concerns for Impairment?

Opinions vary on whether buprenorphine can cause impairment in drivers. Relatively little information on the observed effects of buprenorphine, outside a laboratory or a controlled driving course, exist in the literature. The Wisconsin State Laboratory of Hygiene monitored the detection of buprenorphine and its pharmacologically active metabolite, norbuprenorphine (NBUP), in Wisconsin drivers over a 2-year period. A total of 204 individuals (78 females and 126 males) were driving under the influence of buprenorphine and/or NBUP. Concentrations in whole blood (ng/mL) ranged (mean) from 0.6 to 14 (2.0) and 0.5 to 20 (2.1) for buprenorphine and NBUP, respectively. Poly-substance use is extremely prevalent in Wisconsin operating while intoxicated casework, so prevalent that only four of the previously described cases had buprenorphine and/or NBUP as the only drug(s) detected. This paper summarizes and highlights the case histories and observed impairments of those four cases. Law enforcement (LE) made contact with three of the four subjects due to either a crash or poor/reckless driving. Police reports and observations made by LE, including drug recognition expert (DRE) evaluations, were collected. Physical and behavioral observations made by LE varied and included a combination of narcotic analgesic, central nervous system depressant- and stimulant-like effects. Impaired balance and lack of coordination during the administration of the Standardized Field Sobriety Tests were documented by the arresting officers and/or the DRE. While the number of buprenorphine-only cases reported here is limited, the results demonstrate the complex paradigm associated with forensic interpretation of buprenorphine in driving under the influence of drugs casework and the frequency of poly-substance administration in Wisconsin drivers.

Pharmacological therapies for management of opium withdrawal

BACKGROUND

Pharmacologic therapies for management of heroin withdrawal have been studied and reviewed widely. Opium dependence is generally associated with less severe dependence and milder withdrawal symptoms than heroin. The evidence on withdrawal management of heroin might therefore not be exactly applicable for opium.

OBJECTIVES

To assess the effectiveness and safety of various pharmacologic therapies for the management of the acute phase of opium withdrawal.

SEARCH METHODS

We searched the following sources up to September 2017: CENTRAL, MEDLINE, Embase, CINAHL, PsycINFO, regional and national databases (IMEMR, Iranmedex, and IranPsych), main electronic sources of ongoing trials, and reference lists of all relevant papers. In addition, we contacted known investigators to obtain missing data or incomplete trials.

SELECTION CRITERIA

Controlled clinical trials and randomised controlled trials on pharmacological therapies, compared with no intervention, placebo, other pharmacologic treatments, different doses of the same drug, and psychosocial intervention, to manage acute withdrawal from opium in a maximum duration of 30 days.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included 13 trials involving 1096 participants. No pooled analysis was possible. Studies were carried out in three countries, Iran, India, and Thailand, in outpatient and inpatient settings. The quality of the evidence was generally very low.When the mean of withdrawal symptoms was provided for several days, we mainly focused on day 3. The reason for this was that the highest severity of opium withdrawal is in the second to fourth day.Comparing different pharmacological treatments with each other, clonidine was twice as good as methadone for completion of treatment (risk ratio (RR) 2.01, 95% confidence interval (CI) 1.69 to 2.38; 361 participants, 1 study, low-quality evidence). All the other results showed no differences between the considered drugs: baclofen versus clonidine (RR 1.06, 95% CI 0.63 to 1.80; 66 participants, 1 study, very low-quality evidence); clonidine versus clonidine plus amantadine (RR 1.03, 95% CI 0.86 to 1.24; 69 participants, 1 study); clonidine versus buprenorphine in an inpatient setting (RR 1.04, 95% CI 0.90 to 1.20; 1 study, 35 participants, very low-quality evidence); methadone versus tramadol (RR 0.95, 95% CI 0.65 to 1.37; 1 study, 72 participants, very low-quality evidence); methadone versus methadone plus gabapentin (RR 1.17, 95% CI 0.96 to 1.43; 1 study, 40 participants, low-quality evidence), and tincture of opium versus methadone (1 study, 74 participants, low-quality evidence).Comparing different pharmacological treatments with each other, adding amantadine to clonidine decreased withdrawal scores rated at day 3 (mean difference (MD) -3.56, 95% CI -5.97 to -1.15; 1 study, 60 participants, very low-quality evidence). Comparing clonidine with buprenorphine in an inpatient setting, we found no difference in withdrawal symptoms rated by a physician (MD -1.40, 95% CI -2.93 to 0.13; 1 study, 34 participants, very low-quality evidence), and results in favour of buprenorpine when rated by participants (MD -11.80, 95% CI -15.56 to -8.04). Buprenorphine was superior to clonidine in controlling severe withdrawal symptoms in an outpatient setting (RR 0.35, 95% CI 0.19 to 0.64; 1 study, 76 participants). We found no difference in the comparison of methadone versus tramadol (MD 0.04, 95% CI -2.68 to 2.76; 1 study, 72 participants) and in the comparison of methadone versus methadone plus gabapentin (MD -2.20, 95% CI -6.72 to 2.32; 1 study, 40 participants).Comparing clonidine versus buprenorphine in an outpatient setting, more adverse effects were reported in the clonidine group (1 study, 76 participants). Higher numbers of participants in the clonidine group experienced hypotension at days 5 to 8, headache at days 1 to 8, sedation at days 5 to 8, dizziness and dry mouth at days 1 to 10, and nausea at days 1 to 9. Sweating was reported in a significantly higher number of participants in the buprenorphine group at days 1 to 10. We found no difference between groups for all the other comparisons considering this outcome.Comparing different dosages of the same pharmacological detoxification treatment, a high dose of clonidine (1 to 1.2 mg/day) did not differ from a low dose of clonidine (0.5 to 0.6 mg/day) in completion of treatment in an inpatient setting (RR 1.00, 95% CI 0.84 to 1.19; 1 study, 68 participants), however a higher number of participants with hypotension was reported in the high-dose group (RR 3.25, 95% CI 1.77 to 5.98). Gradual reduction of methadone was associated with more adverse effects than abrupt withdrawal of methadone (RR 2.25, 95% CI 1.02 to 4.94; 1 study, 20 participants, very low-quality evidence).

AUTHORS' CONCLUSIONS

Results did not support using any specific pharmacological approach for the management of opium withdrawal due to generally very low-quality evidence and small or no differences between treatments. However, it seems that opium withdrawal symptoms are significant, especially at days 2 to 4 after discontinuation of opium. All of the assessed medications might be useful in alleviating symptoms. Those who receive clonidine might experience hypotension.

Pharmacokinetics and Pharmacodynamics of Multiple Sublingual Buprenorphine Tablets in Dose-Escalation Trials

In this investigation, the pharmacokinetic and pharmacodynamic properties were determined of multiple doses of sublingual tablets containing either buprenorphine alone or buprenorphine and naloxone. Subjects were experienced opiate users who received escalating doses (4-24 mg) of buprenorphine either alone or in combination with naloxone. Peak concentration (Cmax) and area under the concentration-time curves (AUCs) increased for both buprenorphine and naloxone with escalating doses. Significant differences were found across the range of doses administered for dose-adjusted Cmax for both tablet formulations and for the dose-adjusted AUCs for the buprenorphine-naloxone tablets. For both formulations, the maximal buprenorphine-induced decreases in respiratory rate and pupil diameter did not vary significantly across doses. Several of the subjective effects of buprenorphine did not increase as the dose of buprenorphine administered was increased. These findings are consistent with the ceiling effect associated with the partial agonist actions of buprenorphine. They also indicate a lack of dose proportionality for buprenorphine sublingual tablets, at least during the times at which levels of this agent are highest.

Buprenorphine in the treatment of opioid dependence

Methadone has been the mainstay of pharmacological management of opioid dependence since the 1960s but buprenorphine is fast gaining acceptance among addiction specialists and patients. This article provides an overview of buprenorphine, its pharmacology, clinical efficacy and role in the treatment of opioid dependence.

Buprenorphine-containing treatments: place in the management of opioid addiction

Although the synthetic opioid buprenorphine has been available clinically for almost 30 years, its use has only recently become much more widespread for the treatment of opioid addiction. The pharmacodynamic and pharmacokinetic profiles of buprenorphine make it unique in the armamentarium of drugs for the treatment of opioid addiction. Buprenorphine has partial mu-opioid receptor agonist activity and is a kappa-opioid receptor antagonist; hence, it can substitute for other micro-opioid receptor agonists, yet is less apt to produce overdose reactions or dysphoria. On the other hand, buprenorphine can block the effects of opioids such as heroin (diamorphine) and morphine, and can even precipitate withdrawal in individuals physically dependent upon these drugs. Buprenorphine has significant sublingual bioavailability and a long half-life, making administration on a less than daily basis possible. Furthermore, its discontinuation is associated with only a mild withdrawal syndrome. Clinical trials have demonstrated that sublingual buprenorphine is effective in both maintenance therapy and detoxification of individuals addicted to opioids. The introduction of a sublingual formulation combining naloxone with buprenorphine further reduces the risk of diversion to illicit intravenous use. Because of its relative safety and lower risk of illegal diversion, buprenorphine has been made available in several countries for treating opioid addiction in the private office setting, greatly enhancing treatment options for this condition.

A survey of buprenorphine related deaths in Singapore

Buprenorphine is available in Singapore as substitution treatment for opioid dependence since 2002. This study surveys buprenorphine related deaths in Singapore between September 2003 and December 2004. The aims are to establish the autopsy prevalence of buprenorphine related deaths and the demographical and toxicological profile of the cases. Toxicological screening was performed for all unnatural deaths, deaths involving known drug addicts, as well as when autopsy revealed no obvious cause of death. Twenty-one cases had buprenorphine detected in post-mortem blood and/or urine samples. Eighteen were sudden deaths. There were two fatal falls from height and one death by hanging. All subjects were male. The age range was 24-48 years. Fourteen subjects were between 30 and 39 years of age. The mean age was 35 years. The majority (62%) were Chinese. Eleven (52%) were known drug abusers. For sudden deaths, two groups were identified. Six cases died from natural causes. Blood buprenorphine levels ranged from undetected (detected in urine) to 3.2 ng/mL (mean 1.4 ng/mL). Twelve cases were attributed directly and indirectly to mixed drug poisoning. Blood buprenorphine levels ranged from undetected (detected in urine) to 17 ng/mL (mean 3.2 ng/mL). Nineteen cases showed concurrent abuse of buprenorphine and benzodiazepine, diazepam being the most frequently detected, followed by nitrazepam and midazolam. The availability of buprenorphine as substitution therapy is associated with an increase in buprenorphine related deaths. The danger of co-abuse of buprenorphine and benzodiazepines is highlighted.

Males and females differ in response to opioid agonist medications

Few clinical trials include sex as a factor. This analysis explored within-sex differences in response to opioid agonist medications. Males and females randomly assigned to buprenorphine, LAAM, or methadone were compared on opioid use and retention in treatment. Females receiving buprenorphine had less objective drug use than females receiving methadone, while males receiving LAAM had less objective drug use than males receiving buprenorphine. Retention in treatment was longer for both sexes receiving methadone versus LAAM. Within-subject change results indicate that all three medications benefit both sexes. Clinical trials should be designed to examine the impact of sex on outcomes.

Buprenorphine treatment for opioid dependence: the relative efficacy of daily, twice and thrice weekly dosing

This randomized clinical trial evaluated the relative efficacy of three buprenorphine dosing schedules. Opioid-dependent adults were randomly assigned to receive buprenorphine seven, 3 or 2 days per week for 24 weeks. Daily maintenance doses were 4, 8, 10, or 12 mg of the sublingual buprenorphine solution. Participants who attended the clinic daily received a maintenance dose of buprenorphine daily. Participants who attended the clinic thrice weekly received double their maintenance dose on Monday and Wednesday, followed by a triple dose on Friday. Participants who attended the clinic twice weekly received quadruple their maintenance dose of buprenorphine on Monday and triple their maintenance dose on Friday. Results demonstrated that all dosing regimens were of comparable efficacy in promoting treatment retention, opioid and cocaine abstinence, and reductions in HIV risk behavior (especially as related to drug use) and severity of life problems. Predictor analyses identified sub-populations of opioid-dependent individuals that may have a more positive treatment outcome under each buprenorphine dosing condition. Less-than-daily dosing schedules may provide the opportunity for treatment programs to serve a greater number of opioid-dependent patients and reduce the risk of medication diversion, which may, in turn, have a positive impact on community support of science-based treatment for opioid-dependence.

Opioid detoxification using high doses of buprenorphine in 24 hours: a randomized, double blind, controlled clinical trial

In recent years, interest in shortening of opioid detoxification has increased with the rising demands to find more cost-effective approaches for treatment of opioid dependence. This study was designed to evaluate the efficacy of administration of high doses of buprenorphine during 24 h in the management of acute opioid withdrawal. A total of 40 treatment-seeking opioid dependents were admitted and randomly assigned to two groups in a double blind, parallel trial. Buprenorphine was administered intramuscularly. Twenty patients received 12 mg buprenorphine in 24 h and the remaining 20 patients treated with conventional doses of buprenorphine tapered down over 5 days. Variables that were assessed included retention in treatment, rates of successful detoxification, the Subjective Opiate Withdrawal Scale (OOWS) scores, the Objective Opiate Withdrawal Scale (SOWS) scores, intensity of craving, drug side effects, and levels of hepatic enzymes (ALT and AST). There was no significant difference between the two groups on most variables. The main difference was in the time that maximal withdrawal symptoms occurred, which in the experimental protocol group appeared early while in the conventional protocol group appeared later during the detoxification period. Moreover, the experimental protocol was not only tolerated well but also accompanied with significantly less elevation in the ALT levels compared to the conventional treatment. However, patients in this group used more indomethacin and trazodone for symptom palliation. This study suggests that administration of high doses of buprenorphine in 24 h may be a reasonable approach for shortening of opioid detoxification. However, a larger study to confirm our results is warranted.

The clinical use of buprenorphine in opiate addiction: evidence and practice

Buprenorphine is a partial μ-opioid receptor agonist that is being increasingly used in clinical practice in the treatment of opioid dependence in the UK, USA, and, elsewhere. Its unique pharmacological properties mean it is a relatively safe drug, it can be given by alternate day dispensing, and it is associated with relatively mild symptoms on withdrawal. The interpretation of the research literature on buprenorphine is however, complex, and often appears to be in conflict with how buprenorphine is used in clinical practice. This article describes these apparent contradictions, their likely explanations, and how these may further inform our clinical practice. The article also describes the clinically relevant pharmacological properties of buprenorphine, compares it to methadone, relates the evidence to clinical experience, and provides practical advice on how to manage the most common clinical techniques. The best quality evidence suggests that very rapid buprenorphine induction is not associated with a higher drop-out rate than methadone, that buprenorphine is probably as good as methadone for maintenance treatment, and is superior to methadone and α-2 adrenergic agonists for detoxification. However, buprenorphine cannot yet be considered the 'gold standard' treatment for opiate dependence because of the higher drop-out rates that may occur on induction using current techniques, its high-cost relative to methadone, and because the place of buprenorphine in treatment is still continuing to evolve.

Practical considerations for the clinical use of buprenorphine

Buprenorphine is a new and attractive medication option for many opioid-addicted adults and their physicians. Before initiating buprenorphine treatment, providers must be aware of such critical factors as how the medication works, its efficacy and safety profile, how it is used in opioid withdrawal as well as maintenance treatment, and how patients can best be selected, educated about buprenorphine, and monitored throughout treatment. This article reviews these important issues as well as requirements for physician and staff training and needs for additional research on this unique medication.

Randomized trial of buprenorphine for treatment of concurrent opiate and cocaine dependence

BACKGROUND

Buprenorphine is a partial mu-opiate agonist and kappa-opiate antagonist with established efficacy in the treatment of opiate dependence. Its efficacy for cocaine dependence is uncertain. This study evaluated buprenorphine for the treatment of concomitant cocaine and opiate dependence.

METHODS

Two hundred outpatients currently dependent on both cocaine and opiates were randomly assigned to double-blind groups receiving a sublingual solution of buprenorphine (2, 8, or 16 mg daily, or 16 mg on alternate days, or placebo), plus weekly individual drug abuse counseling, for 13 weeks. The chief outcome measures were urine concentrations of opiate and cocaine metabolites (quantitative) and proportion of urine samples positive for opiates or cocaine (qualitative). Group differences were assessed by use of mixed regression modeling.

RESULTS

The target dose of buprenorphine was achieved in 179 subjects. Subjects receiving 8 or 16 mg buprenorphine daily showed statistically significant decreases in urine morphine levels (P =.0135 for 8 mg and P <.001 for 16 mg) or benzoylecgonine concentrations (P =.0277 for 8 mg and P =.006 for 16 mg) during the maintenance phase of the study. For the 16-mg group, mean benzoylecgonine concentrations fell from 3715 ng/mL during baseline to 186 ng/mL during the withdrawal phase; mean morphine concentrations fell from 3311 ng/mL during baseline to 263 ng/mL during withdrawal. For the 8-mg group, mean benzoylecgonine concentrations fell from 6761 ng/mL during baseline to 676 ng/mL during withdrawal; mean morphine concentrations fell from 3890 ng/mL during baseline to 661 ng/mL during withdrawal. Qualitative urinalysis showed a similar pattern of results. Subjects receiving the highest dose showed concomitant decreases in both urine morphine and benzoylecgonine concentrations. There were no significant group differences in treatment retention or adverse events.

CONCLUSIONS

A sublingual buprenorphine solution at 16 mg daily is well tolerated and effective in reducing concomitant opiate and cocaine use. The therapeutic effect on cocaine use appears independent of that on opiate use.

Buprenorphine versus methadone maintenance therapy: a randomized double-blind trial with 405 opioid-dependent patients

AIMS

To assess the efficacy of buprenorphine compared with methadone maintenance therapy for opioid dependence in a large sample using a flexible dosing regime and the marketed buprenorphine tablet.

DESIGN

Patients were randomized to receive buprenorphine or methadone over a 13-week treatment period in a double-blind, double-dummy trial.

SETTING

Three methadone clinics in Australia.

PARTICIPANTS

Four hundred and five opioid-dependent patients seeking treatment.

INTERVENTION

Patients received buprenorphine or methadone as indicated clinically using a flexible dosage regime. During weeks 1-6, patients were dosed daily. From weeks 7-13, buprenorphine patients received double their week 6 dose on alternate days.

MEASUREMENTS

Retention in treatment, and illicit opioid use as determined by urinalysis. Self-reported drug use, psychological functioning, HIV-risk behaviour, general health and subjective ratings were secondary outcomes.

FINDINGS

Intention-to-treat analyses revealed no significant difference in completion rates at 13 weeks. Methadone was superior to buprenorphine in time to termination over the 13-week period (Wald chi 2 = 4.371, df = 1, P = 0.037), but not separately for the single-day or alternate-day dosing phases. There were no significant between-group differences in morphine-positive urines, or in self-reported heroin or other illicit drug use. The majority (85%) of the buprenorphine patients transferred to alternate-day dosing were maintained in alternate-day dosing.

CONCLUSIONS

Buprenorphine did not differ from methadone in its ability to suppress heroin use, but retained approximately 10% fewer patients. This poorer retention was due possibly to too-slow induction onto buprenorphine. For the majority of patients, buprenorphine can be administered on alternate days.

Endogenous opiates: 2000

This paper is the twenty-third installment of the annual review of research concerning the opiate system. It summarizes papers published during 2000 that studied the behavioral effects of the opiate peptides and antagonists, excluding the purely analgesic effects, although stress-induced analgesia is included. The specific topics covered this year include stress; tolerance and dependence; learning, memory, and reward; eating and drinking; alcohol and other drugs of abuse; sexual activity, pregnancy, and development; mental illness and mood; seizures and other neurological disorders; electrical-related activity; general activity and locomotion; gastrointestinal, renal, and hepatic function; cardiovascular responses; respiration and thermoregulation; and immunological responses.

Buprenorphine and naloxone for heroin dependence

The pharmacology of buprenorphine is unique because of its partial agonist profile at the mu-opioid receptor (ie, high affinity, low intrinsic activity and slow dissociation). This unique profile results in greater safety, less physical dependence, and greater flexibility in dose scheduling. Buprenorphine has been investigated in combination with the opioid antagonist, naloxone, with the goal of decreasing abuse, misuse, and diversion. When combined with naloxone in a sublingual tablet, buprenorphine has been shown to be effective 1) in retaining patients in treatment, 2) in reducing opioid use and craving, and 3) when dosed less-than-daily. The pharmacologic effects of buprenorphine are not altered by the addition of naloxone when administered to the population in an appropriate combination ratio. However, if taken intravenously by individuals dependent on short- or long-acting opioids a precipitated withdrawal syndrome is observed, which should reduce its abuse potential. This review discusses the rationale for development and evidence supporting the use of a buprenorphine/naloxone combination product. The buprenorphine/naloxone combination product should be considered for use in primary care office-based settings as a safe and effective treatment that is likely to increase the availability of agonist treatment for opioid dependence.