Buprenorphine for opioid dependence

The Pharmacological Treatment of Chronic Pain: From Guidelines to Daily Clinical Practice

In agreement with the International Association for the Study of Pain, chronic pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage. To date, there are several types of pain: nociceptive, neuropathic, and nociplastic. In the present narrative review, we evaluated the characteristics of the drugs used for each type of pain, according to guidelines, and their effects in people with comorbidity to reduce the development of severe adverse events.

Depot Buprenorphine Injection In The Management Of Opioid Use Disorder: From Development To Implementation

Buprenorphine has pharmacologic advantages over methadone, especially buprenorphine's better safety profile. The true significance of buprenorphine's introduction lies in returning the care of those suffering from opioid use disorder (OUD) to the hands of the physician. The clinical success of buprenorphine has been meager, in part because most physicians have not been exposed to treating these patients. For physicians inclined to treat OUD, the barriers to buprenorphine's implementation have been onerous and largely counter to the norms of medical practice. Some notable concerns pertain to buprenorphine's clinical pharmacology like street diversion, unintended use and accidental poisoning. Recently, injectable buprenorphine preparations have been introduced to mitigate these latter shortcomings. Yet, the injectable preparations' clinical and commercial success has fallen far short of expectation. Here, we review the clinical pharmacology of these products and their expected clinical advantages for the manufacturers, clinicians, policy makers and patients, and offer our perspective, as clinicians and researchers, on how things can improve. Questions remain whether clinicians are willing to overcome barriers to treat OUD using these medications.

Therapeutic experience with tramadol for opioid dependence in a patient with chronic low back pain: a case report

Background

Long-term opioid treatment for chronic non-cancer pain has become controversial, given the increasing prevalence of opioid dependence. However, there is little information on therapeutic strategies for this condition in Japanese patients. Here, we present a case of successful management of iatrogenic opioid dependence with tramadol in a patient with chronic low back pain.

Case presentation

A 68-year-old male suffering from intractable low back pain was referred to our pain clinic. He was previously treated in another hospital with transdermal fentanyl patches 6 mg/day and fentanyl sublingual tablets (100 μg as required) for this condition. On the basis of medical examination, including a review of the patient’s medical history, physical examination, X-ray, and his family statement, we diagnosed him with iatrogenic opioid dependence due to inadequate fentanyl use. Then, we developed a treatment plan consisting in fentanyl detoxification with a weak opioid, tramadol. At first, the use of fentanyl sublingual tablets was interrupted after obtaining informed consent. Then, we reduced the dose of transdermal fentanyl 1 mg per 4–5 days replacing with oral sustained-release tramadol. The patient developed mild to moderate withdrawal symptoms during this period, which could be effectively managed by supportive treatments. The hospital psychiatry liaison team continuously provided the patient and his wife with information, counseling, and education regarding the treatment of opioid dependence. Throughout the detoxification process, his reported pain did not exacerbate, even slightly improved over time. The final prescription was sustained-release tramadol 300 mg/day without fentanyl, and his activities of daily living drastically improved. However, unfortunately, he died due to an aortic dissection of stent-graft edge 65 days after surgery.

Conclusions

Our case highlighted that sustained-release tramadol could be effectively applied as a detoxification agent for iatrogenic opioid dependence in patients with chronic non-cancer pain.

Decline in Buprenorphine/Naloxone Prescriptions in a State Medicaid Population Following Formulary Conversion from Suboxone to Bunavail

INTRODUCTION

A large, statewide, fee-for-service Medicaid plan recently (October 2015) executed a complete switch from sublingual buprenorphine-naloxone [(SLBN), Suboxone^®] to buccal buprenorphine-naloxone [(BBN), Bunavail^®] on its preferred drug formulary. This complete formulary switch provided an opportunity to assess dynamic changes in prescribing patterns, patient/physician acceptance, and indices of potential misuse/diversion.

METHODS

For the period January 1, 2015 through December 31, 2016, two datasets were analyzed: prescriptions and associated costs for buprenorphine-naloxone (BN) products and urine toxicology test results for patients in the Medicaid plan. The dataset comprised 1370 unique providers ordering 643,225 prescriptions for opioid addiction therapy. Patient and order volumes, and the rate of monthly positive laboratory values for opioid molecules and cocaine were reviewed. A targeted survey of physicians treating opioid-dependent patients with state Medicaid plan coverage was also conducted.

RESULTS

Upon plan conversion to BBN, there was a rapid increase in monthly BBN prescriptions mirrored by a rapid decrease in SLBN prescriptions. Peak in BBN prescriptions (2633 in November 2015) was approximately 60% lower than peak in SLBN prescriptions (6531 in July 2015). An unexpected finding was a 68% reduction of the overall BN market, indicating that many BN prescriptions were abandoned. The reduction was associated with quarterly cost savings to the Medicaid plan of approximately $3.5 million. Toxicology results indicated a reduction in drug positivity (defined as positivity for cocaine and/or any opioids except buprenorphine and methadone) from 13-16% in 2015 to less than 10% in 2016. Heroin positivity decreased from approximately 9% in December 2015 to an average of less than 1% during the last quarter of 2016, while positivity for norbuprenorphine, the major metabolite of buprenorphine, showed a marked increase in 2016 vs 2015. Among physicians who responded to the targeted survey most rated BBN as more difficult to abuse or misuse than SLBN.

CONCLUSION

The rapid reduction in the overall BN market following a complete formulary switch from SLBN to BBN was associated with quarterly savings of $3.5 million for the state Medicaid plan. Toxicology data suggest that this cost saving was realized in the context of improved physician and patient adherence to treatment protocols. The changing market dynamics can potentially be explained by a number of contributory factors, including a reduction of diversion and illicit distribution of BN following formulary conversion. These results are considered hypothesis-generating and future research should systematically compare the propensity for diversion and abuse of BN products using various epidemiological tracking tools.

FUNDING

BioDelivery Sciences International, Inc.

Novel Buccal Film Formulation of Buprenorphine-Naloxone for the Maintenance Treatment of Opioid Dependence: A 12-Week Conversion Study

PURPOSE

The purpose of this study was to provide a preliminary assessment of the safety, tolerability, symptom control, and acceptability of buprenorphine-naloxone buccal film (BBN) for the maintenance treatment of opioid dependence in patients converted from buprenorphine-naloxone sublingual tablet or film (SLBN), as well as to determine the conversion ratio for switching patients from SLBN to BBN.

METHODS

This open-label study included adult opioid-dependent subjects stabilized on 8/2 to 32/8 mg/d of SLBN for a minimum of 30 days. Study subjects were converted to a bioequivalent dose of BBN and maintained for 12 weeks.

FINDINGS

A total of 249 subjects (mean age 38.7 years, 65.9% male) were converted from SLBN to a single daily dose of BBN, and 79.1% completed the 12-week study. Adverse events and withdrawal symptoms led to discontinuation in 2.4% and 2.0% of BBN-treated subjects, respectively. Rates of constipation reported at baseline declined from 41% just before the initial BBN dose and within 24 hours of the last SLBN dose to 13% after 12 weeks of BBN treatment; treatment-emergent constipation was reported by 2.8% of BBN-treated subjects. Oral mucosal abnormalities were identified in 5% and 0.6% of systematic oral examinations in SLBN- and BBN-treated subjects, respectively. A total of 34 subjects had Clinical Opiate Withdrawal Scale total scores ranging from 10 to 25 (overall mean, 13.8) within 24 hours of taking their last SLBN dose, and scores for these subjects were reduced to a range of 0 to 3 (overall mean, 0.7) at 3 hours after the initial dose of BBN. Treatment compliance was high (108%); <1% of urine samples were buprenorphine-free, and 92.4% of BBN-treated subjects did not have a urine sample that tested positive for a non-prescribed opioid. A total of 91.3% subjects rated the taste of BBN as pleasant or neutral, and 82.5% rated BBN ease of use as easy or neutral. The overall mean final dose of BBN was 8.0/1.4 mg/d, yielding a 2:1 buprenorphine conversion ratio.

IMPLICATIONS

Although these results should be considered preliminary due to the open-label design, BBN was overall safe and well tolerated, and seemed to provide adequate symptom control, in the treatment of opioid-dependent subjects previously controlled on SLBN for a minimum of 30 days. There was good adherence to study medication and favorable patient acceptance of the buccal formulation. The SLBN/BBN buprenorphine conversion ratio was 2:1. ClinicalTrials.gov identifier: NCT01666119.

Buprenorphine treatment for narcotic addiction: not without risks

While most clinicians will never prescribe buprenorphine or combined buprenorphine/naloxone, familiarity with the risks of these pharmacological approaches to the treatment of narcotic addiction remains relevant. Overall, medication-assisted treatment has clearly resulted in meaningful gains for a number of individuals who are addicted to narcotics (i.e., opiates and opioids). However, a certain level of risk is inherent with these approaches. For example, both buprenorphine and buprenorphine/naloxone may be diverted and misused (e.g., intravenously injected, intranasally administered), particularly buprenorphine. Likewise, when illicitly injected, both can cause infectious complications as well as result in death from overdose. The risk of death with buprenorphine overdose appears to be heightened with the coadministration of either benzodiazepines or sedative/hypnotics. To conclude, as with all interventions in medicine, buprenorphine treatment for narcotic addiction has a clinically fluctuating risk/benefit equation that must be continually monitored.

Impact of research network participation on the adoption of buprenorphine for substance abuse treatment

There is a growing body of research supporting the use of buprenorphine and other medication assisted treatments (MATs) for the rapidly accelerating opioid epidemic in the United States. Despite numerous advantages of buprenorphine (accessible in primary care, no daily dosing required, minimal stigma), implementation has been slow. As the field progresses, there is a need to understand the impact of participation in practitioner-scientist research networks on acceptance and uptake of buprenorphine. This paper examines the impact of research network participation on counselor attitudes toward buprenorphine addressing both counselor-level characteristics and program-level variables using hierarchical linear modeling (HLM) to account for nesting of counselors within treatment programs. Using data from the National Treatment Center Study, this project compares privately funded treatment programs (N=345) versus programs affiliated with the National Institute on Drug Abuse Clinical Trials Network (CTN) (N=198). Models included 922 counselors in 172 CTN programs and 1203 counselors in 251 private programs. Results of two-level HLM logistic (Bernoulli) models revealed that counselors with higher levels of education, larger caseloads, more buprenorphine-specific training, and less preference for 12-step treatment models were more likely to perceive buprenorphine as acceptable and effective. Furthermore, buprenorphine was 50% more likely to be perceived as effective among counselors working in CTN-affiliated programs as compared to private programs. This study suggests that research network affiliation positively impacts counselors' acceptance and perceptions of buprenorphine. Thus, research network participation can be utilized as a means to promote positive attitudes toward the implementation of innovations including medication assisted treatment.

Modulation of CNS pain circuitry by intravenous and sublingual doses of buprenorphine

Buprenorphine (BUP) is a partial agonist at μ-, δ- and ORL1 (opioid receptor-like)/nociceptin receptors and antagonist at the κ-opioid receptor site. BUP is known to have both analgesic as well as antihyperalgesic effects via its central activity, and is used in the treatment of moderate to severe chronic pain conditions. Recently, it was shown that intravenous (IV) administration of 0.2mg/70 kg BUP modulates the blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) response to acute noxious stimuli in healthy human subjects. The present study extends these observations by investigating the effects of BUP dose and route of administration on central nervous system (CNS) pain circuitry. Specifically, the modulation of evoked pain BOLD responses and resting state functional connectivity was measured following IV (0.1 and 0.2mg/70 kg) and sublingual (SL) (2mg) BUP administration in healthy human subjects. While 0.1mg/70 kg IV BUP is sub-analgesic, both 0.2mg/70 kg IV BUP and 2.0mg SL BUP are analgesic doses of the drug. Evoked BOLD responses were clearly modulated in a dose-dependent manner. The analgesic doses of BUP by both routes of administration yielded a potentiation in limbic/mesolimbic circuitry and attenuation in sensorimotor/sensory-discriminative circuitry. In addition, robust decreases in functional connectivity between the putamen and the sensorimotor/sensory-discriminative structures were observed at the two analgesic doses subsequent to measuring the maximum plasma BUP concentrations (C(max)). The decreases in functional connectivity within the sensorimotor/sensory-discriminative circuitry were also observed to be dose-dependent in the IV administration cohorts. These reproducible and consistent functional CNS measures at clinically effective doses of BUP demonstrate the potential of evoked pain fMRI and resting-state functional connectivity as objective tools that can inform the process of dose selection. Such methods may be useful during early clinical phase evaluation of potential analgesics in drug development.

Co-occurring amphetamine use and associated medical and psychiatric comorbidity among opioid-dependent adults: results from the Clinical Trials Network

Background

In response to the rising rate of treatment admissions related to illicit use of amphetamines (eg, methamphetamine), we examined the prevalence of amphetamine use among treatment-seeking, opioid-dependent adults, explored whether amphetamine users were as likely as nonamphetamine users to enroll in opioid-dependence treatment trials, and determined whether amphetamine users manifested greater levels of medical and psychiatric comorbidity than nonusers.

Methods

The sample included 1257 opioid-dependent adults screened for participation in three-multisite studies of the National Drug Abuse Treatment Clinical Trials Network (CTN001-003), which studied the effectiveness of buprenorphine for opioid detoxification under varying treatment conditions. Patients were recruited from 23 addiction treatment programs across the US. Medical and psychiatric comorbidity were examined by past-month amphetamine use (current vs former) and route of administration. Five mutually exclusive groups were examined, ie, nonusers, current amphetamine injectors, current amphetamine noninjectors, former amphetamine injectors, and former amphetamine noninjectors.

Results

Of the sample (n = 1257), 22.3% had a history of regular amphetamine use. Of the 280 amphetamine users, 30.3% reported injection as their primary route. Amphetamine users were more likely than nonusers to be white and use more substances. Amphetamine users were as likely as nonusers to enroll in treatment trials. Bivariate analyses indicated elevated rates of psychiatric problems (depression, anxiety, hallucinations, cognitive impairment, violence, suicidal thoughts/attempts) and medical illnesses (dermatological, hepatic, cardiovascular, respiratory, neurological, seizure, allergy conditions) among amphetamine users. After adjusting for demographic variables and lifetime use of other substances: current amphetamine users and former injectors showed an increased likelihood of having medical illnesses and hospitalizations; current injectors had elevated odds of suicidal thoughts or attempts; current noninjectors exhibited elevated odds of anxiety, cognitive impairment, and violent behaviors; and former noninjectors had increased odds of depression.

Conclusion

Treatment-seeking, amphetamine-using, opioid-dependent adults manifest greater levels of medical and psychiatric morbidity than treatment-seeking, opioid-dependent adults who have not used amphetamines, indicating a greater need for intensive clinical management.

Anesthesia for patients on buprenorphine

Opioid abuse is a devastating, costly, and growing problem in the United States, and one for which treatment can be complicated by barriers such as access to care and legal issues. Only 12% to 15% of the opioid-dependent population is enrolled in methadone maintenance programs. A significant breakthrough occurred with passage of the Drug Addiction Treatment Act of 2000 (DATA 2000). For the first time in approximately 80 years, physicians could legally prescribe opioid medications for the treatment of opioid addiction. The opiate, so designated, was buprenorphine (Subutex).

Induction of opioid-dependent individuals onto buprenorphine and buprenorphine/naloxone soluble-films

A sublingual soluble-film formulation of buprenorphine/naloxone (B/N) has been approved by the US Food and Drug Administration for the treatment of opioid dependency. This preparation provides unit-dose, child-resistant packaging amenable to tracking and accountability, offers more rapid dissolution, and has a potentially preferred taste vs. tablets. This study compared the ability of buprenorphine (B) and B/N films to suppress spontaneous withdrawal in opioid-dependent volunteers. Participants were maintained on morphine and underwent challenge sessions to confirm sensitivity to naloxone-induced opioid withdrawal. Subjects were randomized to receive either B (16 mg, n = 18) or B/N (16/4 mg, n = 16) soluble films for 5 days. The primary outcome measure was the Clinical Opiate Withdrawal Scale (COWS) score. Thirty-four subjects completed induction onto soluble films. There was a significant decrease in COWS scores but no significant differences between the groups. The results support the use of B and B/N soluble films as safe and effective delivery methods for opioid induction.

Clinical cases in acute intoxication

Over 2.5 million accidental and intentional drug-related poisonings are reported annually in the United States. Early diagnosis and management of patients who present with acute intoxication can significantly reduce both morbidity and mortality. The initial evaluation of patients with suspected or proven intoxications should focus on hemodynamic stability, mental status, and respiratory function. However, early recognition of toxic ingestion is paramount to implementing life-saving treatments. Important historical clues are often found in a social history that considers intravenous drug use, alcohol use, and any access or exposure to illicit substances. A patient's medication list should also be scrutinized for psychoactive or sedative medications, such as tricyclic antidepressants or opioids. In this article we present case-based discussions of the specific diagnosis and management of 5 commonly occurring acute intoxication syndromes.