This information is not for clinical use. These highlights do not include all the information needed to use Zubsolv safely and effectively. Before taking Zubsolv please consult with your doctor. See full prescribing information for Zubsolv.
Indications And Usage
ZUBSOLV is indicated for treatment of opioid dependence. ZUBSOLV should be used as part of a complete treatment plan that includes counseling and psychosocial support. ZUBSOLV contains buprenorphine, a partial opioid agonist, and naloxone, an opioid antagonist, and is indicated for treatment of opioid dependence. ( 1 ) ZUBSOLV should be used as part of a complete treatment plan that includes counseling and psychosocial support. ( 1 )
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Dosage And Administration
|One 2 mg/0.5 mg sublingual buprenorphine/naloxone tablet||One 1.4 mg/0.36 mg ZUBSOLV sublingual tablet|
|4 mg/1 mg buprenorphine/naloxone taken as: • Two 2 mg/0.5 mg sublingual buprenorphine/naloxone tablets||One 2.9 mg/0.71 mg ZUBSOLV sublingual tablet|
|One 8 mg/2 mg sublingual buprenorphine/naloxone tablet||One 5.7 mg/1.4 mg ZUBSOLV sublingual tablet|
|12 mg/3 mg buprenorphine/naloxone, taken as: • One 8 mg/2 mg sublingual buprenorphine/naloxone tablet AND • Two 2 mg/0.5 mg sublingual buprenorphine/naloxone tablets||One 8.6 mg/2.1 mg ZUBSOLV sublingual tablet|
|16 mg/4 mg buprenorphine/naloxone, taken as: • Two 8 mg/2 mg sublingual buprenorphine/naloxone tablets||One 11.4 mg/2.9 mg ZUBSOLV sublingual tablet|
Dosage Forms And Strengths
ZUBSOLV sublingual tablet is supplied in six dosage strengths: • Buprenorphine 0.7 mg /naloxone 0.18 mg, white, oval shape tablets imprinted with “.7” • Buprenorphine 1.4 mg /naloxone 0.36 mg, white, triangular shape tablets imprinted with “1.4” • Buprenorphine 2.9 mg /naloxone 0.71 mg, white, D shape tablets imprinted with “2.9” • Buprenorphine 5.7 mg /naloxone 1.4 mg, white, round shape tablets imprinted with “5.7” • Buprenorphine 8.6 mg /naloxone 2.1 mg, white, diamond shape tablets imprinted with “8.6” • Buprenorphine 11.4 mg /naloxone 2.9 mg, white, capsule shape tablets imprinted with “11.4” Sublingual tablet: • Buprenorphine 0.7 mg /naloxone 0.18 mg, • Buprenorphine 1.4 mg /naloxone 0.36 mg, • Buprenorphine 2.9 mg /naloxone 0.71 mg, • Buprenorphine 5.7 mg /naloxone 1.4 mg, • Buprenorphine 8.6 mg /naloxone 2.1 mg and • Buprenorphine 11.4 mg /naloxone 2.9 mg. ( 3 )
ZUBSOLV is contraindicated in patients with a history of hypersensitivity to buprenorphine or naloxone as serious adverse reactions, including anaphylactic shock, have been reported [ see W a r n i ng s an d Prec au ti o n s ( 5.9 ) ] . Hypersensitivity to buprenorphine or naloxone. ( 4 )
Warning and Cautions
• Addiction, Abuse, and Misuse: Buprenorphine can be abused in a similar manner to other opioids. Monitor patients for conditions indicative of diversion or progression of opioid dependence and addictive behaviors. Multiple refills should not be prescribed early in treatment or without appropriate patient follow-up visits. ( 5.1 ) • Respiratory Depression: Life-threatening respiratory depression and death have occurred in association with buprenorphine use. Warn patients of the potential danger of self-administration of benzodiazepines or other CNS depressants while under treatment with ZUBSOLV. ( 5.2 , 5.3 ) • Unintentional Pediatric Exposure: Store ZUBSOLV safely out of the sight and reach of children. Buprenorphine can cause severe and fatal respiratory depression in children. ( 5.4 ) • Neonatal Opioid Withdrawal Syndrome: Neonatal opioid withdrawal syndrome (NOWS) is an expected and treatable outcome of prolonged use of opioids during pregnancy. ( 5.5 ) • Adrenal Insufficiency: If diagnosed, treat with physiologic replacement of corticosteroids, and wean patient off of the opioid. ( 5.6 ) • Risk of Opioid Withdrawal with Abrupt Discontinuation: If treatment is temporarily interrupted or discontinued, monitor patients for withdrawal and treat appropriately. ( 5.7 ) • Risk of Hepatitis; Hepatic Events: Monitor liver function tests prior to initiation and during treatment and evaluate suspected hepatic events. ( 5.8 ) • Precipitation of Opioid Withdrawal Signs and Symptoms: An opioid withdrawal syndrome is likely to occur with parenteral misuse of ZUBSOLV by individuals physically dependent on full opioid agonists or by sublingual administration before the agonist effects of other opioids have subsided. ( 5.10 ) • Risk of Overdose in Opioid-Naïve Patients: ZUBSOLV is not appropriate as an analgesic. There have been reported deaths of opioid naïve individuals who received a 2 mg equivalent sublingual dose of buprenorphine. ( 5.11 ) 5.1 Addiction, Abuse and Misuse ZUBSOLV contains buprenorphine, a schedule III controlled substance that can be abused in a manner similar to other opioids, legal or illicit. Prescribe and dispense buprenorphine with appropriate precautions to minimize risk of misuse, abuse, or diversion, and ensure appropriate protection from theft, including in the home. Clinical monitoring appropriate to the patient’s level of stability is essential. Multiple refills should not be prescribed early in treatment or without appropriate patient follow-up visits [see Drug Abuse and Dependence ( 9.2 )]. 5.2 Risk of Life-Threatening Respiratory and Central Nervous System (CNS) Depression Buprenorphine has been associated with life-threatening respiratory depression and death. Many, but not all, post-marketing reports regarding coma and death involved misuse by self-injection or were associated with the concomitant use of buprenorphine and benzodiazepines or other CNS depressants, including alcohol. Warn patients of the potential danger of self-administration of benzodiazepines or other CNS depressants while under treatment with ZUBSOLV [see Warnings and Precautions ( 5.3 ), Drug Interactions ( 7 )]. Use ZUBSOLV with caution in patients with compromised respiratory function (e.g., chronic obstructive pulmonary disease, cor pulmonale, decreased respiratory reserve, hypoxia, hypercapnia, or pre-existing respiratory depression). Educate patients and caregivers on how to recognize respiratory depression and emphasize the importance of calling 911 or getting emergency medical help right away in the event of a known or suspected overdose [see Patient Counseling Information ( 17 )]. Opioids can cause sleep-related breathing disorders including central sleep apnea (CSA) and sleep-related hypoxemia. Opioid use increases the risk of CSA in a dose-dependent fashion. In patients who present with CSA, consider decreasing the opioid dosage using best practices for opioid taper [see Dosage and Administration ( 2.9 )]. Patient Access to Naloxone for the Emergency Treatment of Opioid Overdose Discuss the availability of naloxone for the emergency treatment of opioid overdose with the patient and caregiver. Because patients being treated for opioid use disorder have the potential for relapse, putting them at risk for opioid overdose, strongly consider prescribing naloxone for the emergency treatment of opioid overdose, both when initiating and renewing treatment with ZUBSOLV. Also consider prescribing naloxone if the patient has household members (including children) or other close contacts at risk for accidental ingestion or opioid overdose [see Dosage and Administration ( 2.3 )]. Advise patients and caregivers that naloxone may also be administered for a known or suspected overdose with ZUBSOLV itself. Higher than normal doses and repeated administration of naloxone may be necessary due to the long duration of action of ZUBSOLV and its affinity for the mu receptor [see Overdosage ( 10 )]. Inform patients and caregivers of their options for obtaining naloxone as permitted by individual state naloxone dispensing and prescribing requirements or guidelines (e.g., by prescription, directly from a pharmacist, or as part of a community-based program). Educate patients and caregivers on how to recognize respiratory depression and, if naloxone is prescribed, how to treat with naloxone. Emphasize the importance of calling 911 or getting emergency medical help, even if naloxone is administered [see Patient Counseling Information ( 17 )]. 5.3 Managing Risks from Concomitant Use of Benzodiazepines or Other CNS Depressants Concomitant use of buprenorphine and benzodiazepines or other CNS depressants increases the risk of adverse reactions including overdose and death. Medication-assisted treatment of opioid use disorder, however, should not be categorically denied to patients taking these drugs. Prohibiting or creating barriers to treatment can pose an even greater risk of morbidity and mortality due to the opioid use disorder alone. As a routine part of orientation to buprenorphine treatment, educate patients about the risks of concomitant use of benzodiazepines, sedatives, opioid analgesics, and alcohol. Develop strategies to manage use of prescribed or illicit benzodiazepines or other CNS depressants at initiation of buprenorphine treatment, or if it emerges as a concern during treatment. Adjustments to induction procedures and additional monitoring may be required. There is no evidence to support dose limitations or arbitrary caps of buprenorphine as a strategy to address benzodiazepine use in buprenorphine-treated patients. However, if a patient is sedated at the time of buprenorphine dosing, delay or omit the buprenorphine dose if appropriate. Cessation of benzodiazepines or other CNS depressants is preferred in most cases of concomitant use. In some cases, monitoring in a higher level of care for taper may be appropriate. In others, gradually tapering a patient off of a prescribed benzodiazepine or other CNS depressant or decreasing to the lowest effective dose may be appropriate. For patients in buprenorphine treatment, benzodiazepines are not the treatment of choice for anxiety or insomnia. Before co-prescribing benzodiazepines, ensure that patients are appropriately diagnosed and consider alternative medications and non-pharmacologic treatments to address anxiety or insomnia. Ensure that other healthcare providers prescribing benzodiazepines or other CNS depressants are aware of the patient’s buprenorphine treatment and coordinate care to minimize the risks associated with concomitant use. If concomitant use is warranted, strongly consider prescribing naloxone for the emergency treatment of opioid overdose, as is recommended for all patients in buprenorphine treatment for opioid use disorder [see Warnings and Precautions ( 5.2 )]. In addition, take measures to confirm that patients are taking their medications as prescribed and are not diverting or supplementing with illicit drugs. Toxicology screening should test for prescribed and illicit benzodiazepines [see Drug Interactions ( 7 )]. 5.4 Unintentional Pediatric Exposure Buprenorphine can cause fatal respiratory depression in children who are accidentally exposed to it. Store buprenorphine containing medications safely out of the sight and reach of children and destroy any unused medication appropriately [see Patient Counseling Information ( 17 )]. 5.5 Neonatal Opioid Withdrawal Syndrome Neonatal opioid withdrawal syndrome (NOWS) is an expected and treatable outcome of prolonged use of opioids during pregnancy, whether that use is medically-authorized or illicit. Unlike opioid withdrawal syndrome in adults, NOWS may be life-threatening if not recognized and treated in the neonate. Healthcare professionals should observe newborns for signs of NOWS and manage accordingly [see Use in Specific Populations ( 8.1 )]. Advise pregnant women receiving opioid addiction treatment with ZUBSOLV of the risk of neonatal opioid withdrawal syndrome and ensure that appropriate treatment will be available [see Use in Specific Populations ( 8.1 )]. This risk must be balanced against the risk of untreated opioid addiction which often results in continued or relapsing illicit opioid use and is associated with poor pregnancy outcomes. Therefore, prescribers should discuss the importance and benefits of management of opioid addiction throughout pregnancy. 5.6 Adrenal Insufficiency Cases of adrenal insufficiency have been reported with opioid use, more often following greater than one month of use. Presentation of adrenal insufficiency may include non-specific symptoms and signs including nausea, vomiting, anorexia, fatigue, weakness, dizziness, and low blood pressure. If adrenal insufficiency is suspected, confirm the diagnosis with diagnostic testing as soon as possible. If adrenal insufficiency is diagnosed, treat with physiologic replacement doses of corticosteroids. Wean the patient off of the opioid to allow adrenal function to recover and continue corticosteroid treatment until adrenal function recovers. Other opioids may be tried as some cases reported use of a different opioid without recurrence of adrenal insufficiency. The information available does not identify any particular opioids as being more likely to be associated with adrenal insufficiency. 5.7 Risk of Opioid Withdrawal with Abrupt Discontinuation Buprenorphine is a partial agonist at the mu-opioid receptor and chronic administration produces physical dependence of the opioid type, characterized by withdrawal signs and symptoms upon abrupt discontinuation or rapid taper. The withdrawal syndrome is typically milder than seen with full agonists and may be delayed in onset. When discontinuing ZUBSOLV, gradually taper the dosage [see Dosage and Administration ( 2.9 )]. 5.8 Risk of Hepatitis, Hepatic Events Cases of cytolytic hepatitis and hepatitis with jaundice have been observed in individuals receiving buprenorphine in clinical trials and through post-marketing adverse event reports. The spectrum of abnormalities ranges from transient asymptomatic elevations in hepatic transaminases to case reports of death, hepatic failure, hepatic necrosis, hepatorenal syndrome, and hepatic encephalopathy. In many cases, the presence of pre-existing liver enzyme abnormalities, infection with hepatitis B or hepatitis C virus, concomitant usage of other potentially hepatotoxic drugs, and ongoing injecting drug use may have played a causative or contributory role. In other cases, insufficient data were available to determine the etiology of the abnormality. Withdrawal of buprenorphine has resulted in amelioration of acute hepatitis in some cases; however, in other cases no dose reduction was necessary. The possibility exists that buprenorphine had a causative or contributory role in the development of the hepatic abnormality in some cases. Liver function tests, prior to initiation of treatment is recommended to establish a baseline. Periodic monitoring of liver function during treatment is also recommended. A biological and etiological evaluation is recommended when a hepatic event is suspected. Depending on the case, ZUBSOLV may need to be carefully discontinued to prevent withdrawal signs and symptoms and a return by the patient to illicit drug use, and strict monitoring of the patient should be initiated. 5.9 Hypersensitivity Reactions Cases of hypersensitivity to buprenorphine and naloxone containing products have been reported both in clinical trials and in the post-marketing experience. Cases of bronchospasm, angioneurotic edema, and anaphylactic shock have been reported. The most common signs and symptoms include rashes, hives, and pruritus. A history of hypersensitivity to buprenorphine or naloxone is a contraindication to the use of ZUBSOLV. 5.10 Precipitation of Opioid Withdrawal Signs and Symptoms Because it contains naloxone, ZUBSOLV is likely to produce withdrawal signs and symptoms if misused parenterally by individuals dependent on full opioid agonists such as heroin, morphine, or methadone. Because of the partial agonist properties of buprenorphine, ZUBSOLV may precipitate opioid withdrawal signs and symptoms in such persons if administered sublingually before the agonist effects of the opioid have subsided. 5.11 Risk of Overdose in Opioid Naïve Patients There have been reported deaths of opioid naive individuals who received a 2 mg dose of buprenorphine as a sublingual tablet for analgesia. ZUBSOLV is not appropriate as an analgesic. 5.12 Use in Patients with Impaired Hepatic Function Buprenorphine/naloxone products are not recommended in patients with severe hepatic impairment and may not be appropriate for patients with moderate hepatic impairment. The doses of buprenorphine and naloxone in this fixed-dose combination product cannot be individually titrated, and hepatic impairment results in a reduced clearance of naloxone to a much greater extent than buprenorphine. Therefore, patients with severe hepatic impairment will be exposed to substantially higher levels of naloxone than patients with normal hepatic function. This may result in an increased risk of precipitated withdrawal at the beginning of treatment (induction) and may interfere with buprenorphine’s efficacy throughout treatment. In patients with moderate hepatic impairment, the differential reduction of naloxone clearance compared to buprenorphine clearance is not as great as in subjects with severe hepatic impairment. However, buprenorphine/naloxone products are not recommended for initiation of treatment (induction) in patients with moderate hepatic impairment due to the increased risk of precipitated withdrawal. Buprenorphine/naloxone products may be used with caution for maintenance treatment in patients with moderate hepatic impairment who have initiated treatment on a buprenorphine product without naloxone. Patients should be carefully monitored and consideration given to the possibility of naloxone interfering with buprenorphine’s efficacy [see Use in Specific Populations ( 8.6 )]. 5.13 Impairment of Ability to Drive or Operate Machinery ZUBSOLV may impair the mental or physical abilities required for the performance of potentially dangerous tasks such as driving a car or operating machinery, especially during treatment induction and dose adjustment. Caution patients about driving or operating hazardous machinery until they are reasonably certain that ZUBSOLV therapy does not adversely affect his or her ability to engage in such activities. 5.14 Orthostatic Hypotension Like other opioids, ZUBSOLV may produce orthostatic hypotension in ambulatory patients. 5.15 Elevation of Cerebrospinal Fluid Pressure Buprenorphine, like other opioids, may elevate cerebrospinal fluid pressure and should be used with caution in patients with head injury, intracranial lesions, and other circumstances when cerebrospinal pressure may be increased. Buprenorphine can produce miosis and changes in the level of consciousness that may interfere with patient evaluation. 5.16 Elevation of Intracholedochal Pressure Buprenorphine has been shown to increase intracholedochal pressure, as do other opioids, and thus should be administered with caution to patients with dysfunction of the biliary tract. 5.17 Effects in Acute Abdominal Conditions As with other opioids, buprenorphine may obscure the diagnosis or clinical course of patients with acute abdominal conditions.
T h e f o ll o wi n g ser i ou s ad verse re a cti on s a re d escri b ed elsew h ere in t h e l ab eli ng : • Addiction, Abuse, and Misuse [ see W a r n i n g s an d Prec a u ti on s ( 5.1 )] • Respiratory and CNS Depression [ see W a r n i ng s a n d Prec au ti on s ( 5.2 , 5.3 )] • Neonatal Opioid Withdrawal Syndrome [ see W a r n i ng s an d Prec au ti on s ( 5.5 )] • Adrenal Insufficiency [ see W a r n i ng s an d Prec au ti on s ( 5.6 )] • Opioid Withdrawal [ see W a r n i ng s a n d Prec au ti on s ( 5.7 , 5.10 )] • Hepatitis, Hepatic Events [ see W a r n i ng s an d Prec au ti o n s ( 5.8 )] • Hypersensitivity Reactions [ see W a r n i ng s an d Prec au ti o n s ( 5.9 )] • Orthostatic Hypotension [ see W a r n i ng s an d Prec au ti o n s ( 5.14 )] • Elevation of Cerebrospinal Fluid Pressure [ see W a r n i ng s an d Prec au ti on s ( 5.15 )] • Elevation of Intracholedochal Pressure [ see W a r n i ng s a n d Prec au ti on s ( 5.16 )] Adverse events commonly observed with sublingual administration of ZUBSOLV are headache, nausea, vomiting, hyperhidrosis, constipation, signs and symptoms of withdrawal, insomnia, pain, and peripheral edema. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Orexo at 1-888-982-7658, or FDA at 1-800-FDA-1088, or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. ZUBSOLV for use as initial treatment was evaluated in two clinical trials that had identical, blinded, two-day induction phases, comparing ZUBSOLV to generic buprenorphine. On the first day, subjects received an initial dose of ZUBSOLV 1.4 mg/0.36 mg or generic buprenorphine 2 mg, followed by ZUBSOLV 4.2 mg/1.08 mg or generic buprenorphine 6 mg 1.5 hours later. In total, safety data were available for 538 opioid-dependent subjects exposed to ZUBSOLV (buprenorphine/naloxone) sublingual tablets when used for initial treatment. T a ble 1 . Ad v erse Re a cti o ns in ≥ 5 % o f P a tients D u ring the I n ducti o n Ph a se by S y s te m O r ga n Cl a ss a nd Pr e fer r ed Te r m (S a f e ty P o pul at i o n) S y st e m O r ga n C la ss Preferred Term Z UB S O LV (N= 5 3 8 ) G ener i c B U P (N= 530) O v er a ll (N= 1068) N ( %) P a tients w ith a ny Ad v erse Re ac ti o ns 139 (26%) 136 (26%) 275 (26%) G a str o inte s tin a l Dis o rders 64 (12%) 60 (11%) 124 (12%) Nausea 29 (5%) 36 (7%) 65 (6%) Vomiting 25 (5%) 26 (5%) 51 (5%) Ner vo us S y st e m Dis o rders 48 (9%) 44 (8%) 92 (9%) Headache 36 (7%) 35 (7%) 71 (7%) BUP = buprenorphine ZUBSOLV = buprenorphine/naloxone The safety of buprenorphine/naloxone for longer-term use (up to 16 weeks of treatment) was evaluated in previous studies in 497 opioid-dependent subjects. The prospective evaluation of buprenorphine/naloxone was supported by clinical trials using buprenorphine tablets without naloxone and other trials using buprenorphine sublingual solutions. In total, safety data were available from 3214 opioid-dependent subjects exposed to buprenorphine at doses in the range used in treatment of opioid addiction. See Table 2. T a ble 2 . Ad v erse E v ents > 5 % by B o dy S y st e m a nd Tre at m ent G r o up in a 4 - w eek St u dy N ( %) N ( %) B o dy S y st e m / A dv erse E v ent ( C O ST AR T Te r m i n o l ogy) Bupren o rphine/ n a l oxo ne 16 /4 m g /d ay N= 107 Pl a cebo N= 10 7 B o dy a s a Wh o le Asthenia 7 (7%) 7 (7%) Chills 8 (8%) 8 (8%) Headache 39 (37%) 24 (22%) Infection 6 (6%) 7 (7%) Pain 24 (22%) 20 (19%) Pain Abdomen 12 (11%) 7 (7%) Pain Back 4 (4%) 12 (11%) Withdrawal Syndrome 27 (25%) 40 (37%) C a rdi ova scul a r S y st e m Vasodilation 10 (9%) 7 (7%) Di g esti v e S y st e m Constipation 13 (12%) 3 (3%) Diarrhea 4 (4%) 16 (15%) Nausea 16 (15%) 12 (11%) Vomiting 8 (8%) 5 (5%) Ner vo us S y st e m Insomnia 15 (14%) 17 (16%) Respir a t o ry S y st e m Rhinitis 5 (5%) 14 (13%) S k in a nd A ppen dag es Sweating 15 (14%) 11 (10%) The adverse event profile of buprenorphine was also characterized in the dose-controlled study of buprenorphine solution, over a range of doses in four months of treatment. Table 3 shows adverse events reported by at least 5% of subjects in any dose group in the dose-controlled study. T a ble 3 . Ad v erse E v ents (≥ 5 %) by B o dy S y st e m a nd Tre at m ent G r o up in a 16 - w eek Stu d y B o dy S y st e m /Ad v erse E v ent (C O START Te r m i n o l ogy) Bupren o rphine do se* Very L ow * (N= 184) L o w * (N= 180) Mo der a te* (N= 186) H i g h* (N= 181) T o t a l* (N= 731) N ( %) N ( %) N ( %) N ( %) N ( %) B o dy a s a Wh o le Abscess 9 (5%) 2 (1%) 3 (2%) 2 (1%) 16 (2%) Asthenia 26 (14%) 28 (16%) 26 (14%) 24 (13%) 104 (14%) Chills 11 (6%) 12 (7%) 9 (5%) 10 (6%) 42 (6%) Fever 7 (4%) 2 (1%) 2 (1%) 10 (6%) 21 (3%) Flu Syndrome. 4 (2%) 13 (7%) 19 (10%) 8 (4%) 44 (6%) Headache 51 (28%) 62 (34%) 54 (29%) 53 (29%) 220 (30%) Infection 32 (17%) 39 (22%) 38 (20%) 40 (22%) 149 (20%) Injury Accidental 5 (3%) 10 (6%) 5 (3%) 5 (3%) 25 (3%) Pain 47 (26%) 37 (21%) 49 (26%) 44 (24%) 177 (24%) Pain Back 18 (10%) 29 (16%) 28 (15%) 27 (15%) 102 (14%) Withdrawal Syndrome 45 (24%) 40 (22%) 41 (22%) 36 (20%) 162 (22%) Di g esti v e S y st e m Constipation 10 (5%) 23 (13%) 23 (12%) 26 (14%) 82 (11%) Diarrhea 19 (10%) 8 (4%) 9 (5%) 4 (2%) 40 (5%) Dyspepsia 6 (3%) 10 (6%) 4 (2%) 4 (2%) 24 (3%) Nausea 12 (7%) 22 (12%) 23 (12%) 18 (10%) 75 (10%) Vomiting 8 (4%) 6 (3%) 10 (5%) 14 (8%) 38 (5%) Ner vo us S y st e m Anxiety 22 (12%) 24 (13%) 20 (11%) 25 (14%) 91 (12%) Depression 24 (13%) 16 (9%) 25 (13%) 18 (10%) 83 (11%) Dizziness 4 (2%) 9 (5%) 7 (4%) 11 (6%) 31 (4%) Insomnia 42 (23%) 50 (28%) 43 (23%) 51 (28%) 186 (25%) Nervousness 12 (7%) 11 (6%) 10 (5%) 13 (7%) 46 (6%) Somnolence 5 (3%) 13 (7%) 9 (5%) 11 (6%) 38 (5%) Respir a t o ry S y st e m Cough Increase 5 (3%) 11 (6%) 6 (3%) 4 (2%) 26 (4%) Pharyngitis 6 (3%) 7 (4%) 6 (3%) 9 (5%) 28 (4%) Rhinitis 27 (15%) 16 (9%) 15 (8%) 21 (12%) 79 (11%) S k in a nd Append ag es Sweat 23 (13%) 21 (12%) 20 (11%) 23 (13%) 87 (12%) Speci a l Senses Runny Eyes 13 (7%) 9 (5%) 6 (3%) 6 (3%) 34 (5%) *Sublingual solution. Doses in this table cannot necessarily be delivered in tablet form, but for comparison purposes: "Very low" dose (1 mg solution) would be less than a tablet dose of 2 mg "Low" dose (4 mg solution) approximates a 6 mg tablet dose "Moderate" dose (8 mg solution) approximates a 12 mg tablet dose "High" dose (16 mg solution) approximates a 24 mg tablet dose 6.2 Post-marketing Experience The following adverse reactions have been identified during post-approval use of buprenorphine and naloxone sublingual tablets. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate a causal relationship to drug exposure. The most frequently reported post-marketing adverse event not observed in clinical trials was peripheral edema. Serotonin syndrome: Cases of serotonin syndrome, a potentially life-threatening condition, have been reported during concomitant use of opioids with serotonergic drugs. Adrenal insufficiency: Cases of adrenal insufficiency have been reported with opioid use, more often following greater than one month of use. Anaphylaxis: Anaphylaxis has been reported with ingredients contained in ZUBSOLV. Androgen deficiency: Cases of androgen deficiency have occurred with chronic use of opioids [see Clinical Pharmacology ( 12.2 )]. Local reactions: Glossodynia, glossitis, oral mucosal erythema, oral hypoesthesia, and stomatitis
Table 4 includes clinically significant drug interactions with ZUBSOLV. T a ble 4 . Clinic a l l y Si g nific a nt D r u g Inter a cti o ns Ben z o di a z e p ines a nd o ther C entr a l Ner vo us S y st e m (CN S ) De p ress a nts Cli n ic a l Im pa ct: Due to additive pharmacologic effects, the concomitant use of benzodiazepines and other CNS depressants, including alcohol, increases the risk of respiratory depression, profound sedation, coma, and death. I n terve n ti on : Cessation of benzodiazepines or other CNS depressants is preferred in most cases of concomitant use. In some cases, monitoring in a higher level of care for taper may be appropriate. In others, gradually tapering a patient off of a prescribed benzodiazepine or other CNS depressant or decreasing to the lowest effective dose may be appropriate. Before co-prescribing benzodiazepines for anxiety or insomnia, ensure that patients are appropriately diagnosed and consider alternative medications and non-pharmacologic treatments [see Warnings and Precautions ( 5.2 , 5.3 )]. If concomitant use is warranted, strongly consider prescribing naloxone for the emergency treatment of opioid overdose, as is recommended for all patients in treatment for opioid use disorder [see Warnings and Precautions ( 5.2 )]. Ex a m p les: Alcohol, benzodiazepines and other sedatives/hypnotics, anxiolytics, tranquilizers, muscle relaxants, general anesthetics, antipsychotics, and other opioids. Inhibit o rs o f CY P3 A4 Cli n ic a l Im pa ct: The concomitant use of buprenorphine and CYP3A4 inhibitors can increase the plasma concentration of buprenorphine, resulting in increased or prolonged opioid effects, particularly when an inhibitor is added after a stable dose of ZUBSOLV is achieved. After stopping a CYP3A4 inhibitor, as the effects of the inhibitor decline, the buprenorphine plasma concentration will decrease [see Clinical Pharmacology ( 12.3 )] , potentially resulting in decreased opioid efficacy or a withdrawal syndrome in patients who had developed physical dependence to buprenorphine. I n terve n ti on : If concomitant use is necessary, consider dosage reduction of ZUBSOLV until stable drug effects are achieved. Monitor patients for respiratory depression and sedation at frequent intervals. If a CYP3A4 inhibitor is discontinued, consider increasing the ZUBSOLV dosage until stable drug effects are achieved. Monitor for signs of opioid withdrawal. Ex a m p les: Macrolide antibiotics (e.g., erythromycin), azole-antifungal agents (e.g. ketoconazole), protease inhibitors (e.g., ritonavir). CYP 3 A4 Indu c e r s Cli n ic a l Im pa ct: The concomitant use of buprenorphine and CYP3A4 inducers can decrease the plasma concentration of buprenorphine [see Clinical Pharmacology ( 12.3 )] , potentially resulting in decreased efficacy or onset of a withdrawal syndrome in patients who have developed physical dependence to buprenorphine. After stopping a CYP3A4 inducer, as the effects of the inducer decline, the buprenorphine plasma concentration will increase [see Clinical Pharmacology ( 12.3 )] , which could increase or prolong both therapeutic effects and adverse reactions and may cause serious respiratory depression. I n terve n ti on : If concomitant use is necessary, consider increasing the ZUBSOLV dosage until stable drug effects are achieved. Monitor for signs of opioid withdrawal. If a CYP3A4 inducer is discontinued, consider ZUBSOLV dosage reduction and monitor for signs of respiratory depression. Ex a m p les: Rifampin, carbamazepine, phenytoin. Antir e tr ov ir a ls: N o n-Nucle o side Re v erse Tr a nscr i pt a se inhib i t o rs ( NNRTIs) Cli n ic a l Im pa ct: Non-nucleoside reverse transcriptase inhibitors (NNRTIs) are metabolized principally by CYP3A4. Efavirenz, nevirapine, and etravirine are known CYP3A inducers, whereas delavirdine is a CYP3A inhibitor. Significant pharmacokinetic interactions between NNRTIs (e.g., efavirenz and delavirdine) and buprenorphine have been shown in clinical studies, but these pharmacokinetic interactions did not result in any significant pharmacodynamic effects. I n terve n ti on : Patients who are on chronic ZUBSOLV treatment should have their dose monitored if NNRTIs are added to their treatment regimen. Ex a m p les: Efavirenz, nevirapine, etravirine, delavirdine. Antir e tr ov ir a ls: P r o te a se Inhibit o rs (PIs) Cli n ic a l Im pa ct: Studies have shown some antiretroviral protease inhibitors (PIs) with CYP3A4 inhibitory activity (nelfinavir, lopinavir/ritonavir, ritonavir) have little effect on buprenorphine pharmacokinetic and no significant pharmacodynamic effects. Other PIs with CYP3A4 inhibitory activity (atazanavir and atazanavir/ritonavir) resulted in elevated levels of buprenorphine and norbuprenorphine, and patients in one study reported increased sedation. Symptoms of opioid excess have been found in post-marketing reports of patients receiving buprenorphine and atazanavir with and without ritonavir concomitantly. I n terve n ti on : Monitor patients taking ZUBSOLV and atazanavir with and without ritonavir, and reduce dose of ZUBSOLV if warranted. Ex a m p les: Atazanavir, ritonavir. Antir e tr ov ir a ls: Nucle o side R e v e r se Tr a nscript a se I nhibit o rs ( NRTI s ) Cli n ic a l Im pa ct: Nucleoside reverse transcriptase inhibitors (NRTIs) do not appear to induce or inhibit the P450 enzyme pathway, thus no interactions with buprenorphine are expected. I n terve n ti on : None. Ser o t o ner g ic D rug s Cli n ic a l Im pa ct: The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome. I n terve n ti on : If concomitant use is warranted, carefully observe the patient, particularly during treatment initiation and dose adjustment. Discontinue ZUBSOLV if serotonin syndrome is suspected. Ex a m p les: Selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCAs), triptans, 5-HT3 receptor antagonists, drugs that effect the serotonin neurotransmitter system (e.g., mirtazapine, trazodone, tramadol), certain muscle relaxants (i.e., cyclobenzaprine, metaxalone), monoamine oxidase (MAO) inhibitors (those intended to treat psychiatric disorders and also others, such as linezolid and intravenous methylene blue). Mo n oa m ine O x i da se Inhibit o rs ( M A O Is) Cli n ic a l Im pa ct: MAOI interactions with opioids may manifest as serotonin syndrome or opioid toxicity (e.g., respiratory depression, coma) [see Warnings and Precautions ( 5.2 )] I n terve n ti on : The use of ZUBSOLV is not recommended for patients taking MAOIs or within 14 days of stopping such treatment. Ex a m p les: Phenelzine, tranylcypromine, linezolid. M uscle Rel axa nts Cli n ic a l Im pa ct: Buprenorphine may enhance the neuromuscular blocking action of skeletal muscle relaxants and produce an increased degree of respiratory depression. I n terve n ti on : Monitor patients receiving muscle relaxants and ZUBSOLV for signs of respiratory depression that may be greater than otherwise expected and decrease the dosage of ZUBSOLV and/or the muscle relaxant as necessary. Due to the risk of respiratory depression with concomitant use of skeletal muscle relaxants and opioids, strongly consider prescribing naloxone for the emergency treatment of opioid overdose [see Dosage and Administration ( 2.3 ), Warnings and Precautions ( 5.2 , 5.3 )]. Diuretics Cli n ic a l Im pa ct: Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. I n terve n ti on : Monitor patients for signs of diminished diuresis and/or effects on blood pressure and increase the dosage of the diuretic as needed. Antich o liner g ic D ru g s Cli n ic a l Im pa ct: The concomitant use of anticholinergic drugs may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. I n terve n ti on : Monitor patients for signs of urinary retention or reduced gastric motility when ZUBSOLV is used concomitantly with anticholinergic drugs. • Benzodiazepines: Use caution in prescribing ZUBSOLV for patients receiving benzodiazepines or other CNS depressants and warn patients against concomitant self-administration/misuse. ( 7 ) • CYP3A4 Inhibitors and Inducers: Monitor patients starting or ending CYP3A4 inhibitors or inducers for potential over or under dosing. ( 7 ) • Antiretrovirals: Patients who are on chronic buprenorphine treatment should have their dose monitored if NNRTIs are added to their treatment regimen. Monitor patients taking buprenorphine and atazanavir with and without ritonavir, and reduce dose of buprenorphine if warranted. ( 7 ) • Serotonergic Drugs: Concomitant use may result in serotonin syndrome. Discontinue ZUBSOLV if serotonin syndrome is suspected. ( 7 )
Use In Specific Populations
• Lactati on : Buprenorphine passes into mother’s milk. ( 8.2 ) • Geria t ric Pat i e n ts : Monitor for sedation and Respiratory Depression. ( 8.5 ) • M od erate a n d Se v ere H e p atic I m p ai r m en t : Buprenorphine/naloxone products are not recommended in patients with severe hepatic impairment and may not be appropriate for patients with moderate hepatic impairment. ( 8.6 ) 8.1 Pregnancy Risk Summary The data on use of buprenorphine, one of the active ingredients in ZUBSOLV, in pregnancy, are limited; however, these data do not indicate an increased risk of major malformations specifically due to buprenorphine exposure. There are limited data from randomized clinical trials in women maintained on buprenorphine that were not designed appropriately to assess the risk of major malformations [see Data]. Observational studies have reported on congenital malformations among buprenorphine-exposed pregnancies, but were also not designed appropriately to assess the risk of congenital malformations specifically due to buprenorphine exposure [see Data]. The extremely limited data on sublingual naloxone exposure in pregnancy are not sufficient to evaluate a drug-associated risk. Reproductive and developmental studies in rats and rabbits identified adverse events at clinically relevant and higher doses. Embryofetal death was observed in both rats and rabbits administered buprenorphine during the period of organogenesis at doses approximately 6 and 0.3 times, respectively, the human sublingual dose of 16 mg/day of buprenorphine. Pre- and post-natal development studies in rats demonstrated increased neonatal deaths at 0.3 times and above and dystocia at approximately 3 times the human sublingual dose of 16 mg/day of buprenorphine. No clear teratogenic effects were seen when buprenorphine was administered during organogenesis with a range of doses equivalent to or greater than the human sublingual dose of 16 mg/day of buprenorphine. However, increases in skeletal abnormalities were noted in rats and rabbits administered buprenorphine daily during organogenesis at doses approximately 0.6 and approximately equal to the human sublingual dose of 16 mg/day of buprenorphine, respectively. In a few studies, some events such as acephalus and omphalocele were also observed but these findings were not clearly treatment-related [see Data]. Based on animal data, advise pregnant women of the potential risk to a fetus. The estimated background risk of major birth defects and miscarriage for the indicated population are unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively. Clinical Considerations Disease-Associated Maternal and Embryo-fetal Risk Untreated opioid addiction in pregnancy is associated with adverse obstetrical outcomes such as low birth weight, preterm birth, and fetal death. In addition, untreated opioid addiction often results in continued or relapsing illicit opioid use. Dose Adjustment during Pregnancy and the Postpartum Period Dosage adjustments of buprenorphine may be required during pregnancy, even if the patient was maintained on a stable dose prior to pregnancy. Withdrawal signs and symptoms should be monitored closely and the dose adjusted as necessary. Fetal/neonatal Adverse Reactions Neonatal opioid withdrawal syndrome may occur in newborn infants of mothers who are receiving treatment with ZUBSOLV. Neonatal opioid withdrawal syndrome presents as irritability, hyperactivity and abnormal sleep pattern, high pitched cry, tremor, vomiting, diarrhea, and/or failure to gain weight. Signs of neonatal withdrawal usually occur in the first days after birth. The duration and severity of neonatal opioid withdrawal syndrome may vary. Observe newborns for signs of neonatal opioid withdrawal syndrome and manage accordingly [see Warnings and Precautions ( 5.5 )]. Labor or Delivery Opioid-dependent women on buprenorphine maintenance therapy may require additional analgesia during labor. Data H u m a n D a ta Studies have been conducted to evaluate neonatal outcomes in women exposed to buprenorphine during pregnancy. Limited data from trials, observational studies, case series, and case reports on buprenorphine use in pregnancy do not indicate an increased risk of major malformations specifically due to buprenorphine. Several factors may complicate the interpretation of investigations of the children of women who take buprenorphine during pregnancy, including maternal use of illicit drugs, late presentation for prenatal care, infection, poor compliance, poor nutrition, and psychosocial circumstances. Interpretation of data is complicated further by the lack of information on untreated opioid-dependent pregnant women, who would be the most appropriate group for comparison. Rather, women on another form of opioid medication-assisted treatment, or women in the general population are generally used as the comparison group. However, women in these comparison groups may be different from women prescribed buprenorphine-containing products with respect to maternal factors that may lead to poor pregnancy outcomes. In a multicenter, double-blind, randomized, controlled trial [Maternal Opioid Treatment: Human Experimental Research (MOTHER)] designed primarily to assess neonatal opioid withdrawal effects, opioid-dependent pregnant women were randomized to buprenorphine (n=86) or methadone (n=89) treatment, with enrollment at an average gestational age of 18.7 weeks in both groups. A total of 28 of the 86 women in the buprenorphine group (33%) and 16 of the 89 women in the methadone group (18%) discontinued treatment before the end of pregnancy. Among women who remained in treatment until delivery, there was no difference between buprenorphine-treated and methadone-treated groups in the number of neonates requiring NOWS treatment or in the peak severity of NOWS. Buprenorphine-exposed neonates required less morphine (mean total dose, 1.1 mg vs. 10.4 mg), had shorter hospital stays (10.0 days vs. 17.5 days), and shorter duration of treatment for NOWS (4.1 days vs. 9.9 days) compared to the methadone-exposed group. There were no differences between groups in other primary outcomes (neonatal head circumference,) or secondary outcomes (weight and length at birth, preterm birth, gestational age at delivery, and 1-minute and 5-minute Apgar scores), or in the rates of maternal or neonatal adverse events. The outcomes among mothers who discontinued treatment before delivery and may have relapsed to illicit opioid use are not known. Because of the imbalance in discontinuation rates between the buprenorphine and methadone groups, the study findings are difficult to interpret. Animal Data ZUBSOLV has been shown to have differences in bioavailability compared to other buprenorphine/naloxone-containing sublingual products. The exposure margins listed below are based on body surface area comparisons (mg/m 2 ) to the human sublingual dose of 16 mg buprenorphine via Suboxone, which is equivalent to a human sublingual dose of 11.4 mg buprenorphine via ZUBSOLV. Effects on embryo-fetal development were studied in Sprague-Dawley rats and Russian white rabbits following oral (1:1) and intramuscular (IM) (3:2) administration of mixtures of buprenorphine and naloxone during the period of organogenesis. Following oral administration to rats, no teratogenic effects were observed at buprenorphine doses up to 250 mg/kg/day (estimated exposure approximately 150 times the human sublingual dose of 16 mg) in the presence of maternal toxicity (mortality). Following oral administration to rabbits, no teratogenic effects were observed at buprenorphine doses up to 40 mg/kg/day (estimated exposure approximately 50 times the human sublingual dose of 16 mg) in the absence of clear maternal toxicity. No definitive drug-related teratogenic effects were observed in rats and rabbits at IM doses up to 30 mg/kg/day (estimated exposure approximately 20 times and 35 times, respectively, the human sublingual dose of 16 mg). Maternal toxicity resulting in mortality was noted in these studies in both rats and rabbits. Acephalus was observed in one rabbit fetus from the low-dose group and omphalocele was observed in two rabbit fetuses from the same litter in the mid-dose group; no findings were observed in fetuses from the high-dose group. Maternal toxicity was seen in the high-dose group but not at the lower doses where the findings were observed. Following oral administration of buprenorphine to rats, dose-related post- implantation losses, evidenced by increases in the numbers of early resorptions with consequent reductions in the numbers of fetuses, were observed at doses of 10 mg/kg/day or greater (estimated exposure approximately 6 times the human sublingual dose of 16 mg). In the rabbit, increased post-implantation losses occurred at an oral dose of 40 mg/kg/day. Following IM administration in the rat and the rabbit, post-implantation losses, as evidenced by decreases in live fetuses and increases in resorptions, occurred at 30 mg/kg/day. Buprenorphine was not teratogenic in rats or rabbits after IM or subcutaneous (SC) doses up to 5 mg/kg/day (estimated exposure was approximately 3 and 6 times, respectively, the human sublingual dose of 16 mg), after IV doses up to 0.8 mg/kg/day (estimated exposure was approximately 0.5 times and equal to, respectively, the human sublingual dose of 16 mg), or after oral doses up to 160 mg/kg/day in rats (estimated exposure was approximately 95 times the human sublingual dose of 16 mg) and 25 mg/kg/day in rabbits (estimated exposure was approximately 30 times the human sublingual dose of 16 mg). Significant increases in skeletal abnormalities (e.g., extra thoracic vertebra or thoraco-lumbar ribs) were noted in rats after SC administration of 1 mg/kg/day and up (estimated exposure was approximately 0.6 times the human sublingual dose of 16 mg), but were not observed at oral doses up to 160 mg/kg/day. Increases in skeletal abnormalities in rabbits after IM administration of 5 mg/kg/day (estimated exposure was approximately 6 times the human daily sublingual dose of 16 mg) in the absence of maternal toxicity or oral administration of 1 mg/kg/day or greater (estimated exposure was approximately equal to the human sublingual dose of 16 mg) were not statistically significant. In rabbits, buprenorphine produced statistically significant pre-implantation losses at oral doses of 1 mg/kg/day or greater and post-implantation losses that were statistically significant at IV doses of 0.2 mg/kg/day or greater (estimated exposure approximately 0.3 times the human sublingual dose of 16 mg). No maternal toxicity was noted at doses causing post-implantation loss in this study. Dystocia was noted in pregnant rats treated intramuscularly with buprenorphine from Gestation Day 14 through Lactation Day 21 at 5 mg/kg/day (approximately 3 times the human sublingual dose of 16 mg). Fertility, pre-, and post-natal development studies with buprenorphine in rats indicated increases in neonatal mortality after oral doses of 0.8 mg/kg/day and up (approximately 0.5 times the human sublingual dose of 16 mg), after IM doses of 0.5 mg/kg/day and up (approximately 0.3 times the human sublingual dose of 16 mg), and after SC doses of 0.1 mg/kg/day and up (approximately 0.06 times the human sublingual dose of 16 mg). An apparent lack of milk production during these studies likely contributed to the decreased pup viability and lactation indices. Delays in the occurrence of righting reflex and startle response were noted in rat pups at an oral dose of 80 mg/kg/day (approximately 50 times the human sublingual dose of 16 mg). 8.2 Lactation Risk Summary Based on two studies in 13 lactating women, maintained on buprenorphine treatment, buprenorphine and its metabolite norbuprenorphine were present in low levels in human milk and available data have not shown adverse reactions in breastfed infants. There are no data on the combination product buprenorphine/naloxone in breastfeeding, however oral absorption of naloxone is limited. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for ZUBSOLV and any potential adverse effects on the breastfed child from the drug or from the underlying maternal condition. Clinical Considerations Advise the breastfeeding women taking buprenorphine products to monitor the infant for increased drowsiness and breathing difficulties. Data Data were consistent from two studies (N=13) of breastfeeding infants whose mothers were maintained on sublingual doses of buprenorphine ranging from 2.4 to 24 mg/day, showing that the infants were exposed to less than 1% of the maternal daily dose. In a study of six lactating women who were taking a median sublingual buprenorphine dose of 0.29 mg/kg/day 5 to 8 days after delivery, breast milk provided a median infant dose of 0.42 mcg/kg/day of buprenorphine and 0.33 mcg/kg/day of norbuprenorphine, equal to 0.2% and 0.12%, respectively, of the maternal weight-adjusted dose (relative dose/kg (%) of norbuprenorphine was calculated from the assumption that buprenorphine and norbuprenorphine are equipotent). Data from a study of seven lactating women who were taking a median sublingual buprenorphine dose of 7 mg/day an average of 1.12 months after delivery indicated that the mean milk concentrations (C avg ) of buprenorphine and norbuprenorphine were 3.65 mcg/L and 1.94 mcg/L respectively. Based on the study data, and assuming milk consumption of 150 mL/kg/day, an exclusively breastfed infant would receive an estimated mean absolute infant dose (AID) of 0.55 mcg/kg/day of buprenorphine and 0.29 mcg/kg/day of norbuprenorphine, or a mean relative infant dose (RID) of 0.38% and 0.18%, respectively, of the maternal weight-adjusted dose. 8.3 Females and Males of Reproductive Potential I nf ertility Chronic use of opioids may cause reduced fertility in females and males of reproductive potential. It is not known whether these effects on fertility are reversible [see Adverse Reactions ( 6.2 ), Nonclinical Toxicology ( 13.1 )]. 8.4 Pediatric Use The safety and effectiveness of ZUBSOLV have not been established in pediatric patients. This product is not appropriate for the treatment of neonatal opioid withdrawal syndrome in neonates, because it contains naloxone, an opioid antagonist. 8.5 Geriatric Use Clinical studies of buprenorphine/naloxone sublingual tablets did not include sufficient numbers of subjects aged 65 and over to determine whether they responded differently than younger subjects. Other reported clinical experience have not identified differences in responses between the elderly and younger patients. Due to possible decreased hepatic, renal, or cardiac function and of concomitant disease or other drug therapy in geriatric patients, the decision to prescribe ZUBSOLV should be made cautiously in individuals 65 years of age or older and these patients should be monitored for signs and symptoms of toxicity or overdose. 8.6 Hepatic Impairment The effect of hepatic impairment on the pharmacokinetics of buprenorphine and naloxone has been evaluated in a pharmacokinetic study. Both drugs are extensively metabolized in the liver. While no clinically significant changes have been observed in subjects with mild hepatic impairment; the plasma levels have been shown to be higher and half-life values have been shown to be longer for both buprenorphine and naloxone in subjects with moderate and severe hepatic impairment. The magnitude of the effects on naloxone is greater than that on buprenorphine in both moderately and severely impaired subjects. The difference in magnitude of the effects on naloxone and buprenorphine are greater in subjects with severe hepatic impairment than in subjects with moderate hepatic impairment, and therefore the clinical impact of these effects is likely to be greater in patients with severe hepatic impairment than in patients with moderate hepatic impairment. Buprenorphine/naloxone products should be avoided in patients with severe hepatic impairment and may not be appropriate for patients with moderate hepatic impairment [see Warnings and Precautions ( 5.12 ), Clinical Pharmacology ( 12.3 )]. 8.7 Renal Impairment No differences in buprenorphine pharmacokinetics were observed between 9 dialysis-dependent and 6 normal patients following IV administration of 0.3 mg buprenorphine. The effects of renal failure on naloxone pharmacokinetics are unknown [see Clinical Pharmacology ( 12.3 )].