Chantix (Varenicline tartrate): Uses, Dosage, Side Effects & Warnings

Uses

1 INDICATIONS AND USAGE CHANTIX is indicated for use as an aid to smoking-cessation treatment. CHANTIX is a nicotinic receptor partial agonist indicated for use as an aid to smoking-cessation treatment. ( 1 and 2.1 )

Dosage and administration

• Begin CHANTIX dosing one week before the date set by the patient to stop smoking. Alternatively, the patient can begin CHANTIX dosing and then quit smoking between days 8 and 35 of treatment. ( 2.1 )
• Starting Week: 0.5 mg once daily on days 1–3 and 0.5 mg twice daily on days 4–7. ( 2.1 )
• Continuing Weeks: 1 mg twice daily for a total of 12 weeks. ( 2.1 )
• An additional 12 weeks of treatment is recommended for successful quitters to increase likelihood of long-term abstinence. ( 2.1 )
• Consider a gradual approach to quitting smoking with CHANTIX for patients who are sure that they are not able or willing to quit abruptly. Patients should begin CHANTIX dosing and reduce smoking by 50% from baseline within the first four weeks, by an additional 50% in the next four weeks, and continue reducing with the goal of reaching complete abstinence by 12 weeks. Continue treatment for an additional 12 weeks, for a total of 24 weeks. ( 2.1 )
• Severe Renal Impairment (estimated creatinine clearance less than 30 mL/min): Begin with 0.5 mg once daily and titrate to 0.5 mg twice daily. For patients with end-stage renal disease undergoing hemodialysis, a maximum of 0.5 mg daily may be given if tolerated. ( 2.2 )
• Consider dose reduction for patients who cannot tolerate adverse effects. ( 2.1 )
• Another attempt at treatment is recommended for those who fail to stop smoking or relapse when factors contributing to the failed attempt have been addressed. ( 2.1 )
• Provide patients with appropriate educational materials and counseling to support the quit attempt. ( 2.1 ) 2.1 Recommended Dosage for Adults Smoking-cessation therapies are more likely to succeed for patients who are motivated to stop smoking and who are provided additional advice and support. Provide patients with appropriate educational materials and counseling to support the quit attempt. The patient should set a date to stop smoking. Begin CHANTIX dosing one week before this date. Alternatively, the patient can begin CHANTIX dosing and then quit smoking between days 8 and 35 of treatment. CHANTIX should be taken orally after eating and with a full glass of water. The recommended dose of CHANTIX is 1 mg twice daily following a 1-week titration as follows: Days 1 – 3: 0.5 mg once daily Days 4 – 7: 0.5 mg twice daily Day 8 – end of treatment: 1 mg twice daily Patients should be treated with CHANTIX for 12 weeks. For patients who have successfully stopped smoking at the end of 12 weeks, an additional course of 12 weeks treatment with CHANTIX is recommended to further increase the likelihood of long-term abstinence. For patients who are sure that they are not able or willing to quit abruptly, consider a gradual approach to quitting smoking with CHANTIX. Patients should begin CHANTIX dosing and reduce smoking by 50% from baseline within the first four weeks, by an additional 50% in the next four weeks, and continue reducing with the goal of reaching complete abstinence by 12 weeks. Continue CHANTIX treatment for an additional 12 weeks, for a total of 24 weeks of treatment. Encourage patients to attempt quitting sooner if they feel ready [see Clinical Studies (14.5) ]. Patients who are motivated to quit, and who did not succeed in stopping smoking during prior CHANTIX therapy for reasons other than intolerability due to adverse events or who relapsed after treatment, should be encouraged to make another attempt with CHANTIX once factors contributing to the failed attempt have been identified and addressed. Consider a temporary or permanent dose reduction in patients who cannot tolerate the adverse effects of CHANTIX. 2.2 Dosage in Special Populations Patients with Impaired Renal Function No dosage adjustment is necessary for patients with mild-to-moderate renal impairment. For patients with severe renal impairment (estimated creatinine clearance less than 30 mL per min), the recommended starting dose of CHANTIX is 0.5 mg once daily. The dose may then be titrated as needed to a maximum dose of 0.5 mg twice daily. For patients with end-stage renal disease undergoing hemodialysis, a maximum dose of 0.5 mg once daily may be administered if tolerated [see Use in Specific Populations (8.6) , Clinical Pharmacology (12.3) ] . Elderly and Patients with Impaired Hepatic Function No dosage adjustment is necessary for patients with hepatic impairment. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function [see Use in Specific Populations (8.5) ] .

Dosage forms and strengths

Capsular, biconvex tablets: 0.5 mg (white to off-white, debossed with " Pfizer " on one side and "CHX 0.5" on the other side) and 1 mg (light blue, debossed with " Pfizer " on one side and "CHX 1.0" on the other side). Tablets: 0.5 mg and 1 mg ( 3 )

Contraindications

4 CONTRAINDICATIONS CHANTIX is contraindicated in patients with a known history of serious hypersensitivity reactions or skin reactions to CHANTIX. History of serious hypersensitivity or skin reactions to CHANTIX. ( 4 )

Warnings and precautions

• Neuropsychiatric Adverse Events: Postmarketing reports of serious or clinically significant neuropsychiatric adverse events have included changes in mood (including depression and mania), psychosis, hallucinations, paranoia, delusions, homicidal ideation, aggression, hostility, agitation, anxiety, and panic, as well as suicidal ideation, suicide attempt, and completed suicide. Observe patients attempting to quit smoking with CHANTIX for the occurrence of such symptoms and instruct them to discontinue CHANTIX and contact a healthcare provider if they experience such adverse events. ( 5.1 )
• Seizures : New or worsening seizures have been observed in patients taking CHANTIX. CHANTIX should be used cautiously in patients with a history of seizures or other factors that can lower the seizure threshold. ( 5.2 )
• Interaction with Alcohol : Increased effects of alcohol have been reported. Instruct patients to reduce the amount of alcohol they consume until they know whether CHANTIX affects them. ( 5.3 )
• Accidental Injury : Accidental injuries (e.g., traffic accidents) have been reported. Instruct patients to use caution driving or operating machinery until they know how CHANTIX may affect them. ( 5.4 )
• Cardiovascular Events : Patients with underlying cardiovascular (CV) disease may be at increased risk of CV events; however, these concerns must be balanced with the health benefits of smoking cessation. Instruct patients to notify their healthcare providers of new or worsening CV symptoms and to seek immediate medical attention if they experience signs and symptoms of myocardial infarction (MI) or stroke. ( 5.5 and 6.1 )
• Somnambulism : Cases of somnambulism have been reported in patients taking CHANTIX. Some cases described harmful behavior to self, others, or property. Instruct patients to discontinue CHANTIX and notify their healthcare provider if they experience somnambulism. ( 5.6 and 6.2 )
• Angioedema and Hypersensitivity Reactions : Such reactions, including angioedema, infrequently life-threatening, have been reported. Instruct patients to discontinue CHANTIX and immediately seek medical care if symptoms occur. ( 5.7 and 6.2 )
• Serious Skin Reactions : Rare, potentially life-threatening skin reactions have been reported. Instruct patients to discontinue CHANTIX and contact a healthcare provider immediately at first appearance of skin rash with mucosal lesions. ( 5.8 and 6.2 )
• Nausea : Nausea is the most common adverse reaction (up to 30% incidence rate). Dose reduction may be helpful. ( 5.9 ) 5.1 Neuropsychiatric Adverse Events including Suicidality Serious neuropsychiatric adverse events have been reported in patients being treated with CHANTIX [see Adverse Reactions (6.2) ] . These postmarketing reports have included changes in mood (including depression and mania), psychosis, hallucinations, paranoia, delusions, homicidal ideation, aggression, hostility, agitation, anxiety, and panic, as well as suicidal ideation, suicide attempt, and completed suicide. Some patients who stopped smoking may have been experiencing symptoms of nicotine withdrawal, including depressed mood. Depression, rarely including suicidal ideation, has been reported in smokers undergoing a smoking-cessation attempt without medication. However, some of these adverse events occurred in patients taking CHANTIX who continued to smoke. Neuropsychiatric adverse events occurred in patients without and with pre-existing psychiatric disease; some patients experienced worsening of their psychiatric illnesses. Some neuropsychiatric adverse events, including unusual and sometimes aggressive behavior directed to oneself or others, may have been worsened by concomitant use of alcohol [see Warnings and Precautions (5.3) , Adverse Reactions (6.2) ]. Observe patients for the occurrence of neuropsychiatric adverse events. Advise patients and caregivers that the patient should stop taking CHANTIX and contact a healthcare provider immediately if agitation, depressed mood, or changes in behavior or thinking that are not typical for the patient are observed, or if the patient develops suicidal ideation or suicidal behavior. The healthcare provider should evaluate the severity of the symptoms and the extent to which the patient is benefiting from treatment, and consider options including dose reduction, continued treatment under closer monitoring, or discontinuing treatment. In many postmarketing cases, resolution of symptoms after discontinuation of CHANTIX was reported. However, the symptoms persisted in some cases; therefore, ongoing monitoring and supportive care should be provided until symptoms resolve. The neuropsychiatric safety of CHANTIX was evaluated in a randomized, double-blind, active and placebo-controlled study that included patients without a history of psychiatric disorder (non-psychiatric cohort, N=3912) and patients with a history of psychiatric disorder (psychiatric cohort, N=4003). In the non-psychiatric cohort, CHANTIX was not associated with an increased incidence of clinically significant neuropsychiatric adverse events in a composite endpoint comprising anxiety, depression, feeling abnormal, hostility, agitation, aggression, delusions, hallucinations, homicidal ideation, mania, panic, and irritability. In the psychiatric cohort, there were more events reported in each treatment group compared to the non-psychiatric cohort, and the incidence of events in the composite endpoint was higher for each of the active treatments compared to placebo: Risk Differences (RDs) (95%CI) vs. placebo were 2.7% (-0.05, 5.4) for CHANTIX, 2.2% (-0.5, 4.9) for bupropion, and 0.4% (-2.2, 3.0) for transdermal nicotine. In the non-psychiatric cohort, neuropsychiatric adverse events of a serious nature were reported in 0.1% of CHANTIX-treated patients and 0.4% of placebo-treated patients.

Side effects

The following serious adverse reactions were reported in postmarketing experience and are discussed in greater detail in other sections of the labeling:
• Neuropsychiatric Adverse Events including Suicidality [see Warnings and Precautions (5.1) ]
• Seizures [see Warnings and Precautions (5.2) ]
• Interaction with Alcohol [see Warnings and Precautions (5.3) ]
• Accidental Injury [see Warnings and Precautions (5.4) ]
• Cardiovascular Events [see Warnings and Precautions (5.5) ]
• Somnambulism [see Warnings and Precautions (5.6) ]
• Angioedema and Hypersensitivity Reactions [see Warnings and Precautions (5.7) ]
• Serious Skin Reactions [see Warnings and Precautions (5.8) ] In the placebo-controlled premarketing studies, the most common adverse events associated with CHANTIX (>5% and twice the rate seen in placebo-treated patients) were nausea, abnormal (vivid, unusual, or strange) dreams, constipation, flatulence, and vomiting. The treatment discontinuation rate due to adverse events in patients dosed with 1 mg twice daily was 12% for CHANTIX, compared to 10% for placebo in studies of three months' treatment. In this group, the discontinuation rates that are higher than placebo for the most common adverse events in CHANTIX-treated patients were as follows: nausea (3% vs. 0.5% for placebo), insomnia (1.2% vs. 1.1% for placebo), and abnormal dreams (0.3% vs. 0.2% for placebo). Smoking cessation, with or without treatment, is associated with nicotine withdrawal symptoms and has also been associated with the exacerbation of underlying psychiatric illness. Most common adverse reactions (>5% and twice the rate seen in placebo-treated patients) were nausea, abnormal (e.g., vivid, unusual, or strange) dreams, constipation, flatulence, and vomiting. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Pfizer Inc. at 1-800-438-1985 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, the adverse reactions rates observed in the clinical studies of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. During the premarketing development of CHANTIX, over 4500 subjects were exposed to CHANTIX, with over 450 treated for at least 24 weeks and approximately 100 for a year. Most study participants were treated for 12 weeks or less. The most common adverse event associated with CHANTIX treatment is nausea, occurring in 30% of patients treated at the recommended dose, compared with 10% in patients taking a comparable placebo regimen [see Warnings and Precautions (5.9) ] . Table 1 shows the adverse events for CHANTIX and placebo in the 12- week fixed dose premarketing studies with titration in the first week [Studies 2 (titrated arm only), 4, and 5]. Adverse events were categorized using the Medical Dictionary for Regulatory Activities (MedDRA, Version 7.1). MedDRA High Level Group Terms (HLGT) reported in ≥5% of patients in the CHANTIX 1 mg twice daily dose group, and more commonly than in the placebo group, are listed, along with subordinate Preferred Terms (PT) reported in ≥1% of CHANTIX patients (and at least 0.5% more frequent than placebo). Closely related Preferred Terms such as 'Insomnia', 'Initial insomnia', 'Middle insomnia', 'Early morning awakening' were grouped, but individual patients reporting two or more grouped events are only counted once. Table 1. Common Treatment Emergent AEs (%) in the Fixed-Dose, Placebo-Controlled Studies (HLGTs ≥5% of Patients in the 1 mg BID CHANTIX Group and More Commonly than Placebo and PT ≥1% in the 1 mg BID CHANTIX Group, and 1 mg BID CHANTIX at Least 0.5% More than Placebo) SYSTEM ORGAN CLASS High Level Group Term CHANTIX 0.5 mg BID CHANTIX 1 mg BID Placebo Preferred Term N=129 N=821 N=805 GASTROINTESTINAL (GI) GI Signs and Symptoms Nausea 16 30 10 Abdominal Pain Includes PTs Abdominal (pain, pain upper, pain lower, discomfort, tenderness, distension) and Stomach discomfort 5 7 5 Flatulence 9 6 3 Dyspepsia 5 5 3 Vomiting 1 5 2 GI Motility/Defecation Conditions Constipation 5 8 3 Gastroesophageal reflux disease 1 1 0 Salivary Gland Conditions Dry mouth 4 6 4 PSYCHIATRIC DISORDERS Sleep Disorder/Disturbances Insomnia Includes PTs Insomnia/Initial insomnia/Middle insomnia/Early morning awakening 19 18 13 Abnormal dreams 9 13 5 Sleep disorder 2 5 3 Nightmare 2 1 0 NERVOUS SYSTEM Headaches Headache 19 15 13 Neurological Disorders NEC Dysgeusia 8 5 4 Somnolence 3 3 2 Lethargy 2 1 0 GENERAL DISORDERS General Disorders NEC Fatigue/Malaise/Asthenia 4 7 6 RESPIR/THORACIC/MEDIAST Respiratory Disorders NEC Rhinorrhea 0 1 0 Dyspnea 2 1 1 Upper Respiratory Tract Disorder 7 5 4 SKIN/SUBCUTANEOUS TISSUE Epidermal and Dermal Conditions Rash 1 3 2 Pruritis 0 1 1 METABOLISM and NUTRITION Appetite/General Nutrition Disorders Increased appetite 4 3 2 Decreased appetite/Anorexia 1 2 1 The overall pattern and frequency of adverse events during the longer-term premarketing trials was similar to those described in Table 1, though several of the most common events were reported by a greater proportion of patients with long-term use (e.g., nausea was reported in 40% of patients treated with CHANTIX 1 mg twice daily in a one year study, compared to 8% of placebo-treated patients). Following is a list of treatment-emergent adverse events reported by patients treated with CHANTIX during all premarketing clinical trials and updated based on pooled data from 18 placebo-controlled pre- and postmarketing studies, including approximately 5,000 patients treated with varenicline. Adverse events were categorized using MedDRA, Version 16.0.

Drug interactions

Based on varenicline characteristics and clinical experience to date, CHANTIX has no clinically meaningful pharmacokinetic drug interactions [see Clinical Pharmacology (12.3) ].
• Other Smoking-Cessation Therapies: Safety and efficacy in combination with other smoking-cessation therapies has not been established. Coadministration of varenicline and transdermal nicotine resulted in a high rate of discontinuation due to adverse events. ( 7.1 )
• Effect of Smoking Cessation on Other Drugs: Pharmacokinetics or pharmacodynamics of certain drugs (e.g., theophylline, warfarin, insulin) may be altered, necessitating dose adjustment. ( 7.2 ) 7.1 Use with Other Drugs for Smoking Cessation Safety and efficacy of CHANTIX in combination with other smoking cessation therapies have not been studied. Bupropion Varenicline (1 mg twice daily) did not alter the steady-state pharmacokinetics of bupropion (150 mg twice daily) in 46 smokers. The safety of the combination of bupropion and varenicline has not been established. Nicotine replacement therapy (NRT ) Although co-administration of varenicline (1 mg twice daily) and transdermal nicotine (21 mg/day) for up to 12 days did not affect nicotine pharmacokinetics, the incidence of nausea, headache, vomiting, dizziness, dyspepsia, and fatigue was greater for the combination than for NRT alone. In this study, eight of twenty-two (36%) patients treated with the combination of varenicline and NRT prematurely discontinued treatment due to adverse events, compared to 1 of 17 (6%) of patients treated with NRT and placebo. 7.2 Effect of Smoking Cessation on Other Drugs Physiological changes resulting from smoking cessation, with or without treatment with CHANTIX, may alter the pharmacokinetics or pharmacodynamics of certain drugs (e.g., theophylline, warfarin, insulin) for which dosage adjustment may be necessary.

Use in specific populations

8.1 Pregnancy Risk Summary Available data have not suggested an increased risk for major birth defects following exposure to varenicline in pregnancy, compared with women who smoke [see Data ]. Smoking during pregnancy is associated with maternal, fetal, and neonatal risks (see Clinical Considerations ) . In animal studies, varenicline did not result in major malformations but caused decreased fetal weights in rabbits when dosed during organogenesis at exposures equivalent to 50 times the exposure at the maximum recommended human dose (MRHD). Additionally, administration of varenicline to pregnant rats during organogenesis through lactation produced developmental toxicity in offspring at maternal exposures equivalent to 36 times human exposure at the MRHD [see Data ] . The estimated background risk of oral clefts is increased by approximately 30% in infants of women who smoke during pregnancy, compared to pregnant women who do not smoke. The background risk of other major birth defects and miscarriage for the indicated population are unknown. In the US 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/or Embryo/Fetal Risk Smoking during pregnancy causes increased risks of orofacial clefts, premature rupture of membranes, placenta previa, placental abruption, ectopic pregnancy, fetal growth restriction and low birth weight, stillbirth, preterm delivery and shortened gestation, neonatal death, sudden infant death syndrome and reduction of lung function in infants. It is not known whether quitting smoking with CHANTIX during pregnancy reduces these risks. Data Human Data A population-based observational cohort study using the national registers of Denmark and Sweden compared pregnancy and birth outcomes among women exposed to varenicline (N=335, includes 317 first trimester exposed) with women who smoked during pregnancy (N=78,412) and with non-smoking pregnant women (N=806,438). The prevalence of major malformations, the primary outcome, was similar in all groups, including between smoking and non-smoking groups. The prevalence of adverse perinatal outcomes in the varenicline-exposed cohort was not greater than in the cohort of women who smoked, and differed somewhat between the three cohorts. The prevalences of the primary and secondary outcomes are shown in Table 6. Table 6. Summary of Primary and Secondary Outcomes for Three Birth Cohorts Outcome Varenicline Cohort (n=335) Smoking Cohort (n=78,412) Non-Smoking Cohort (n=806,438) Major congenital malformation Included only live births in the cohorts. Prevalence among first trimester varenicline-exposed pregnancies (11/317 [3.5%]). 12 / 334 (3.6%) 3,382 / 78,028 (4.3%) 33,950 /804,020 (4.2%) Stillbirth 1 (0.3%) 384 (0.5%) 2,418 (0.3%) Small for gestational age 42 (12.5%) 13,433 (17.1%) 73,135 (9.1%) Preterm birth 25 (7.5%) 6,173 (7.9%) 46,732 (5.8%) Premature rupture of membranes 12 (3.6%) 4,246 (5.4%) 30,641 (3.8%) Sudden infant death syndrome There was a lag in death data in Denmark, so the cohorts were smaller. 0/307 (0.0%) 51/71,720 (0.1%) 58/755,939 (<0.1%) The study limitations include the inability to capture malformations in pregnancies that do not result in a live birth, and possible misclassification of outcome and of exposure to varenicline or to smoking. Other small epidemiological studies of pregnant women exposed to varenicline did not identify an association with major malformations, consistent with the Danish and Swedish observational cohort study. Methodological limitations of these studies include small samples and lack of adequate controls. Overall, available studies cannot definitely establish or exclude any varenicline-associated risk during pregnancy. Animal Data Pregnant rats and rabbits received varenicline succinate during organogenesis at oral doses up to 15 and 30 mg/kg/day, respectively. While no fetal structural abnormalities occurred in either species, maternal toxicity, characterized by reduced body weight gain, and reduced fetal weights occurred in rabbits at the highest dose (exposures 50 times the human exposure at the MRHD of 1 mg twice daily based on AUC). Fetal weight reduction did not occur in rabbits at exposures 23 times the human exposure at the MRHD based on AUC. In a pre- and postnatal development study, pregnant rats received up to 15 mg/kg/day of oral varenicline succinate from organogenesis through lactation. Maternal toxicity, characterized by a decrease in body weight gain was observed at 15 mg/kg/day (36 times the human exposure at the MRHD based on AUC). However, decreased fertility and increased auditory startle response occurred in offspring at the highest maternal dose of 15 mg/kg/day. 8.2 Lactation Risk Summary There are no data on the presence of varenicline in human milk, the effects on the breastfed infant, or the effects on milk production. In animal studies varenicline was present in milk of lactating rats [see Data ] . However, due to species-specific differences in lactation physiology, animal data may not reliably predict drug levels in human milk. The lack of clinical data during lactation precludes a clear determination of the risk of CHANTIX to an infant during lactation; however the developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for CHANTIX and any potential adverse effects on the breastfed child from CHANTIX or from the underlying maternal condition. Clinical Considerations Because there are no data on the presence of varenicline in human milk and the effects on the breastfed infant, breastfeeding women should monitor their infant for seizures and excessive vomiting, which are adverse reactions that have occurred in adults that may be clinically relevant in breastfeeding infants.

Pregnancy

8.1 Pregnancy Risk Summary Available data have not suggested an increased risk for major birth defects following exposure to varenicline in pregnancy, compared with women who smoke [see Data ]. Smoking during pregnancy is associated with maternal, fetal, and neonatal risks (see Clinical Considerations ) . In animal studies, varenicline did not result in major malformations but caused decreased fetal weights in rabbits when dosed during organogenesis at exposures equivalent to 50 times the exposure at the maximum recommended human dose (MRHD). Additionally, administration of varenicline to pregnant rats during organogenesis through lactation produced developmental toxicity in offspring at maternal exposures equivalent to 36 times human exposure at the MRHD [see Data ] . The estimated background risk of oral clefts is increased by approximately 30% in infants of women who smoke during pregnancy, compared to pregnant women who do not smoke. The background risk of other major birth defects and miscarriage for the indicated population are unknown. In the US 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/or Embryo/Fetal Risk Smoking during pregnancy causes increased risks of orofacial clefts, premature rupture of membranes, placenta previa, placental abruption, ectopic pregnancy, fetal growth restriction and low birth weight, stillbirth, preterm delivery and shortened gestation, neonatal death, sudden infant death syndrome and reduction of lung function in infants. It is not known whether quitting smoking with CHANTIX during pregnancy reduces these risks. Data Human Data A population-based observational cohort study using the national registers of Denmark and Sweden compared pregnancy and birth outcomes among women exposed to varenicline (N=335, includes 317 first trimester exposed) with women who smoked during pregnancy (N=78,412) and with non-smoking pregnant women (N=806,438). The prevalence of major malformations, the primary outcome, was similar in all groups, including between smoking and non-smoking groups. The prevalence of adverse perinatal outcomes in the varenicline-exposed cohort was not greater than in the cohort of women who smoked, and differed somewhat between the three cohorts. The prevalences of the primary and secondary outcomes are shown in Table 6. Table 6. Summary of Primary and Secondary Outcomes for Three Birth Cohorts Outcome Varenicline Cohort (n=335) Smoking Cohort (n=78,412) Non-Smoking Cohort (n=806,438) Major congenital malformation Included only live births in the cohorts. Prevalence among first trimester varenicline-exposed pregnancies (11/317 [3.5%]). 12 / 334 (3.6%) 3,382 / 78,028 (4.3%) 33,950 /804,020 (4.2%) Stillbirth 1 (0.3%) 384 (0.5%) 2,418 (0.3%) Small for gestational age 42 (12.5%) 13,433 (17.1%) 73,135 (9.1%) Preterm birth 25 (7.5%) 6,173 (7.9%) 46,732 (5.8%) Premature rupture of membranes 12 (3.6%) 4,246 (5.4%) 30,641 (3.8%) Sudden infant death syndrome There was a lag in death data in Denmark, so the cohorts were smaller. 0/307 (0.0%) 51/71,720 (0.1%) 58/755,939 (<0.1%) The study limitations include the inability to capture malformations in pregnancies that do not result in a live birth, and possible misclassification of outcome and of exposure to varenicline or to smoking. Other small epidemiological studies of pregnant women exposed to varenicline did not identify an association with major malformations, consistent with the Danish and Swedish observational cohort study. Methodological limitations of these studies include small samples and lack of adequate controls. Overall, available studies cannot definitely establish or exclude any varenicline-associated risk during pregnancy. Animal Data Pregnant rats and rabbits received varenicline succinate during organogenesis at oral doses up to 15 and 30 mg/kg/day, respectively. While no fetal structural abnormalities occurred in either species, maternal toxicity, characterized by reduced body weight gain, and reduced fetal weights occurred in rabbits at the highest dose (exposures 50 times the human exposure at the MRHD of 1 mg twice daily based on AUC). Fetal weight reduction did not occur in rabbits at exposures 23 times the human exposure at the MRHD based on AUC. In a pre- and postnatal development study, pregnant rats received up to 15 mg/kg/day of oral varenicline succinate from organogenesis through lactation. Maternal toxicity, characterized by a decrease in body weight gain was observed at 15 mg/kg/day (36 times the human exposure at the MRHD based on AUC). However, decreased fertility and increased auditory startle response occurred in offspring at the highest maternal dose of 15 mg/kg/day.

Pediatric use

8.4 Pediatric Use CHANTIX is not recommended for use in pediatric patients 16 years of age or younger because its efficacy in this population was not demonstrated. Single and multiple-dose pharmacokinetics of varenicline have been investigated in pediatric patients aged 12 to 17 years old (inclusive) and were approximately dose-proportional over the 0.5 mg to 2 mg daily dose range studied. Steady-state systemic exposure in adolescent patients of bodyweight >55 kg, as assessed by AUC (0-24), was comparable to that noted for the same doses in the adult population. When 0.5 mg BID was given, steady-state daily exposure of varenicline was, on average, higher (by approximately 40%) in adolescent patients with bodyweight ≤55 kg compared to that noted in the adult population. The efficacy and safety of varenicline was evaluated in a randomized, double-blind, placebo-controlled study of 312 patients aged 12 to 19 years, who smoked an average of at least 5 cigarettes per day during the 30 days prior to recruitment, had a score of at least 4 on the Fagerstrom Test for Nicotine Dependence scale, and at least one previous failed quit attempt. Patients were stratified by age (12 to 16 years of age, n=216 and 17 to 19 years of age, n=96) and by body weight (≤55 kg and >55 kg). Patients were randomized to one of two doses of varenicline, adjusted by weight to provide plasma levels in the efficacious range (based on adult studies) and placebo. Patients received treatment for 12 weeks, followed by a non-treatment period of 40 weeks, along with age-appropriate counseling throughout the study. Results from this study showed that varenicline, at either dose studied, did not improve continuous abstinence rates at weeks 9 through 12 of treatment compared with placebo in subjects 12 to 19 years of age. The varenicline safety profile in this study was consistent with that observed in adult studies.

Geriatric use

8.5 Geriatric Use A combined single- and multiple-dose pharmacokinetic study demonstrated that the pharmacokinetics of 1 mg varenicline given once daily or twice daily to 16 healthy elderly male and female smokers (aged 65–75 years) for 7 consecutive days was similar to that of younger subjects. No overall differences in safety or effectiveness were observed between these subjects and younger subjects, and other reported clinical experience has not identified differences in responses between the elderly and younger patients, but greater sensitivity of some older individuals cannot be ruled out. Varenicline is known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function [see Dosage and Administration (2.2) ] . No dosage adjustment is recommended for elderly patients.

Overdosage

In case of overdose, standard supportive measures should be instituted as required. Varenicline has been shown to be dialyzed in patients with end-stage renal disease [see Clinical Pharmacology (12.3) ], however, there is no experience in dialysis following overdose.

Description

11 DESCRIPTION CHANTIX tablets contain varenicline (as the tartrate salt), which is a partial nicotinic agonist selective for α 4 β 2 nicotinic acetylcholine receptor subtypes. Varenicline, as the tartrate salt, is a powder which is a white to off-white to slightly yellow solid with the following chemical name: 7,8,9,10-tetrahydro-6,10-methano-6 H -pyrazino[2,3- h][3]benzazepine, (2 R ,3 R )-2,3-dihydroxybutanedioate (1:1). It is highly soluble in water. Varenicline tartrate has a molecular weight of 361.35 Daltons, and a molecular formula of C 13 H 13 N 3 ∙ C 4 H 6 O 6 . The chemical structure is: CHANTIX is supplied for oral administration in two strengths: a 0.5 mg capsular biconvex, white to off-white, film-coated tablet debossed with " Pfizer " on one side and "CHX 0.5" on the other side and a 1 mg capsular biconvex, light blue film-coated tablet debossed with " Pfizer " on one side and "CHX 1.0" on the other side. Each 0.5 mg CHANTIX tablet contains 0.85 mg of varenicline tartrate equivalent to 0.5 mg of varenicline free base; each 1 mg CHANTIX tablet contains 1.71 mg of varenicline tartrate equivalent to 1 mg of varenicline free base. The following inactive ingredients are included in the tablets: microcrystalline cellulose, anhydrous dibasic calcium phosphate, croscarmellose sodium, colloidal silicon dioxide, magnesium stearate, Opadry® White (for 0.5 mg), Opadry® Blue (for 1 mg), and Opadry® Clear. Chemical Structure

Mechanism of action

12.1 Mechanism of Action Varenicline binds with high affinity and selectivity at α4β2 neuronal nicotinic acetylcholine receptors. The efficacy of CHANTIX in smoking cessation is believed to be the result of varenicline's activity at α4β2 sub-type of the nicotinic receptor where its binding produces agonist activity, while simultaneously preventing nicotine binding to these receptors. Electrophysiology studies in vitro and neurochemical studies in vivo have shown that varenicline binds to α4β2 neuronal nicotinic acetylcholine receptors and stimulates receptor-mediated activity, but at a significantly lower level than nicotine. Varenicline blocks the ability of nicotine to activate α4β2 receptors and thus to stimulate the central nervous mesolimbic dopamine system, believed to be the neuronal mechanism underlying reinforcement and reward experienced upon smoking. Varenicline is highly selective and binds more potently to α4β2 receptors than to other common nicotinic receptors (>500-fold α3β4, >3,500-fold α7, >20,000-fold α1βγδ), or to non-nicotinic receptors and transporters (>2,000-fold). Varenicline also binds with moderate affinity (Ki = 350 nM) to the 5-HT3 receptor.

How supplied

16 HOW SUPPLIED/STORAGE AND HANDLING CHANTIX is supplied for oral administration in two strengths: a 0.5 mg capsular biconvex, white to off-white, film-coated tablet debossed with " Pfizer " on one side and "CHX 0.5" on the other side and a 1 mg capsular biconvex, light blue film-coated tablet debossed with " Pfizer " on one side and "CHX 1.0" on the other side. CHANTIX is supplied in the following package configurations: Description NDC Packs Starting 4-week card: 0.5 mg × 11 tablets and 1 mg × 42 tablets NDC 0069-0471-28 Continuing 4-week card: 1 mg × 56 tablets NDC 0069-0469-28 Bottles 0.5 mg - bottle of 56 NDC 0069-0468-56 1 mg - bottle of 56 NDC 0069-0469-56 Store at 25ºC (77ºF); excursions permitted to 15ºC to 30ºC (59ºF to 86ºF) (see USP Controlled Room Temperature).

Storage

Store at 25ºC (77ºF); excursions permitted to 15ºC to 30ºC (59ºF to 86ºF) (see USP Controlled Room Temperature).

Patient information

See FDA-approved patient labeling (Medication Guide) Initiate Treatment and Continue to Attempt to Quit if Lapse Instruct patients to set a date to quit smoking and to initiate CHANTIX treatment one week before the quit date. Alternatively, the patient can begin CHANTIX dosing and then set a date to quit smoking between days 8 and 35 of treatment. Encourage patients to continue to attempt to quit if they have early lapses after quit day [see Dosage and Administration (2.1) ]. For patients who are sure that they are not able or willing to quit abruptly, a gradual approach to quitting smoking with CHANTIX may be considered. Patients should begin CHANTIX dosing and reduce smoking during the first 12 weeks of treatment, then quit by the end of that period and continue treatment for an additional 12 weeks for a total of 24 weeks [see Dosage and Administration (2.1) ] . Encourage patients who are motivated to quit and who did not succeed in stopping smoking during prior CHANTIX therapy for reasons other than intolerability due to adverse events, or who relapsed after treatment to make another attempt with CHANTIX once factors contributing to the failed attempt have been identified and addressed [see Dosage and Administration (2.1) , Clinical Studies (14.6) ]. How to Take Advise patients that CHANTIX should be taken orally after eating, and with a full glass of water [see Dosage and Administration (2.1) ]. Starting Week Dosage Instruct patients on how to titrate CHANTIX, beginning at a dose of 0.5 mg/day. Explain that one 0.5 mg tablet should be taken daily for the first three days, and that for the next four days, one 0.5 mg tablet should be taken in the morning and one 0.5 mg tablet should be taken in the evening [see Dosage and Administration (2.1) ]. Continuing Weeks Dosage Advise patients that, after the first seven days, the dose should be increased to one 1 mg tablet in the morning and one 1 mg tablet in the evening [see Dosage and Administration (2.1) ]. Dosage Adjustment for CHANTIX or Other Drugs Inform patients that nausea and insomnia are side effects of CHANTIX and are usually transient; however, advise patients that if they are persistently troubled by these symptoms, they should notify the prescribing physician so that a dose reduction can be considered. Inform patients that some drugs may require dose adjustment after quitting smoking [see Dosage and Administration (2.1) ]. Counseling and Support Provide patients with educational materials and necessary counseling to support an attempt at quitting smoking [see Dosage and Administration (2.1) ]. Neuropsychiatric Adverse Events Inform patients that some patients have experienced changes in mood (including depression and mania), psychosis, hallucinations, paranoia, delusions, homicidal ideation, aggression, hostility, agitation, anxiety, and panic, as well as suicidal ideation and suicide when attempting to quit smoking while taking CHANTIX. Instruct patients to discontinue CHANTIX and contact a healthcare professional if they experience such symptoms [see Warnings and Precautions (5.1) , Adverse Reactions (6.2) ]. History of Psychiatric Illness Encourage patients to reveal any history of psychiatric illness prior to initiating treatment. Nicotine Withdrawal Inform patients that quitting smoking, with or without CHANTIX, may be associated with nicotine withdrawal symptoms (including depression or agitation) or exacerbation of pre-existing psychiatric illness. Seizures Encourage patients to report any history of seizures or other factors that can lower seizure threshold. Instruct patients to discontinue CHANTIX and contact a healthcare provider immediately if they experience a seizure while on treatment [see Warnings and Precautions (5.2) ] . Interaction with Alcohol Advise patients to reduce the amount of alcohol they consume while taking CHANTIX until they know whether CHANTIX affects their tolerance for alcohol [see Warnings and Precautions (5.3) , Adverse Reactions (6.2) ] . Driving or Operating Machinery Advise patients to use caution driving or operating machinery until they know how quitting smoking and/or varenicline may affect them [see Warnings and Precautions (5.4) ]. Cardiovascular Events Patients should be instructed to notify their healthcare providers of symptoms of new or worsening cardiovascular events and to seek immediate medical attention if they experience signs and symptoms of myocardial infarction or stroke [see Warnings and Precautions (5.5) , Adverse Reactions (6.1) ] . Somnambulism Patients should be instructed to discontinue CHANTIX and notify their healthcare providers if they experience somnambulism [see Warnings and Precautions (5.6) ] . Angioedema Inform patients that there have been reports of angioedema, with swelling of the face, mouth (lip, gum, tongue) and neck (larynx and pharynx) that can lead to life-threatening respiratory compromise. Instruct patients to discontinue CHANTIX and immediately seek medical care if they experience these symptoms [see Warnings and Precautions (5.7) , Adverse Reactions (6.2) ]. Serious Skin Reactions Inform patients that serious skin reactions, such as Stevens-Johnson Syndrome and erythema multiforme, were reported by some patients taking CHANTIX. Advise patients to stop taking CHANTIX at the first sign of rash with mucosal lesions or skin reaction and contact a healthcare provider immediately [see Warnings and Precautions (5.8) , Adverse Reactions (6.2) ]. Vivid, Unusual, or Strange Dreams Inform patients that they may experience vivid, unusual or strange dreams during treatment with CHANTIX. Pregnancy and Lactation Patients who are pregnant or breastfeeding or planning to become pregnant should be advised of: the risks of smoking to a pregnant mother and her developing baby, the potential risks of CHANTIX use during pregnancy and breastfeeding, and the benefits of smoking cessation with and without CHANTIX.

Active ingredients

Varenicline Tartrate in 4 products

Chantix NDC products (6)

NDC	Strength & form	Labeler	Type
43353-899	Varenicline Tartrate 1 mg/1 Tablet, Film Coated	Aphena Pharma Solutions - Tennessee, LLC	NDA
0069-0468	Varenicline Tartrate .5 mg/1 Tablet, Film Coated	Pfizer Laboratories Div Pfizer Inc	NDA
0069-0469	Varenicline Tartrate 1 mg/1 Tablet, Film Coated	Pfizer Laboratories Div Pfizer Inc	NDA
0069-0471	Kit	Pfizer Laboratories Div Pfizer Inc	NDA
63187-618	Kit	Proficient Rx LP	NDA
71205-381	Varenicline Tartrate 1 mg/1 Tablet, Film Coated	Proficient Rx LP	NDA

Chantix recalls

D-0809-2021 Sep 29, 2021 · Class II · Ongoing
CGMP Deviations: Presence of the N-nitroso-varenicline impurity above FDA s acceptable interim acceptable intake limit
D-0810-2021 Sep 29, 2021 · Class II · Ongoing
CGMP Deviations: Presence of the N-nitroso-varenicline impurity above FDA s acceptable interim acceptable intake limit
D-0699-2021 Aug 11, 2021 · Class II · Ongoing
CGMP Deviations: Presence of the N-nitroso-varenicline impurity above FDA s acceptable interim acceptable intake limit
D-0700-2021 Aug 11, 2021 · Class II · Ongoing
CGMP Deviations: Presence of the N-nitroso-varenicline impurity above FDAs acceptable interim acceptable intake limit
D-0701-2021 Aug 11, 2021 · Class II · Ongoing
CGMP Deviations: Presence of the N-nitroso-varenicline impurity above FDAs acceptable interim acceptable intake limit
D-0555-2021 Jun 2, 2021 · Class II · Terminated
CGMP Deviations: Intermittent exposure to temperature excursion during storage.
D-0556-2021 Jun 2, 2021 · Class II · Terminated
CGMP Deviations: Intermittent exposure to temperature excursion during storage.

Frequently asked questions

What is Chantix used for?

1 INDICATIONS AND USAGE CHANTIX is indicated for use as an aid to smoking-cessation treatment. CHANTIX is a nicotinic receptor partial agonist indicated for use as an aid to smoking-cessation treatment. ( 1 and 2.1 )

What are the side effects of Chantix?

The following serious adverse reactions were reported in postmarketing experience and are discussed in greater detail in other sections of the labeling: • Neuropsychiatric Adverse Events including Suicidality [see Warnings and Precautions (5.1) ] • Seizures [see Warnings and Precautions (5.2) ] • Interaction with Alcohol [see Warnings and Precautions (5.3) ] • Accidental Injury [see Warnings and… See the full label for the complete list.

Who makes Chantix?

Chantix is listed by 3 labelers in the FDA NDC directory, including Aphena Pharma Solutions - Tennessee, LLC, Pfizer Laboratories Div Pfizer Inc, Proficient Rx LP.

Has Chantix been recalled?

The FDA enforcement database lists 7 recalls for Chantix, most recently D-0809-2021 (class ii): CGMP Deviations: Presence of the N-nitroso-varenicline impurity above FDA s acceptable interim acceptable intake limit