During the premarketing development of CHANTIX, over 4500 individuals 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.
In Phase 2 and 3 placebo-controlled studies, the treatment discontinuation rate due to adverse events in patients dosed with 1 mg BID was 12% for CHANTIX compared to 10% for placebo in studies of three months' treatment. In this group, the discontinuation rates for the most common adverse events in CHANTIX treated patients were as follows: nausea (3% vs. 0.5% for placebo), headache (0.6% vs. 0.9% for placebo), insomnia (1.2% vs. 1.1% for placebo), and abnormal dreams (0.3% vs. 0.2% for placebo).
Adverse Events were categorized using the Medical Dictionary for Regulatory Activities (MedDRA, Version 7.1).
The most common adverse events associated with CHANTIX ( > 5% and twice the rate seen in placebo-treated patients) were nausea, sleep disturbance, constipation, flatulence, and vomiting.
Smoking cessation, with or without treatment, is associated with nicotine withdrawal symptoms.
The most common adverse event associated with CHANTIX treatment is nausea. For patients treated to the maximum recommended dose of 1 mg BID following initial dosage titration, the incidence of nausea was 30% compared with 10% in patients taking a comparable placebo regimen. In patients taking CHANTIX 0.5 mg BID following initial titration, the incidence was 16% compared with 11% for placebo. Nausea was generally described as mild or moderate and often transient; however, for some subjects, it was persistent throughout the treatment period.
Table 3 shows the adverse events for CHANTIX and placebo in the 12 week fixed dose studies with titration in the first week (Studies 2 (titrated arm only), 4, and 5). MedDRA High Level Group Terms (HLGT) reported in ≥ 5% of patients in the CHANTIX 1 mg BID 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 3: Common Treatment Emergent AEs (%) in the Fixed-Dose,
Placebo-Controlled Studies ( ≥ 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
Preferred Term |
CHANTIX
0.5 mg BID
N=129 |
CHANTIX
1 mg BID
N=821 |
Placebo
N=805 |
| GASTROINTESTINAL |
| GI Signs and Symptoms |
| Nausea |
16 |
30 |
10 |
| Abdominal Pain* |
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 ** |
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 |
| Dyspnoea |
2 |
1 |
1 |
| Upper Respiratory Tract Disorder |
7 |
5 |
4 |
| SKIN/SUBCUTANEOUS TISSUE |
| Epidermal and Dermal Conditions |
| Rash |
1 |
3 |
2 |
| Pruritus |
0 |
1 |
1 |
| METABOLISM & NUTRITION |
| Appetite/General Nutrit. Disorders |
| Increased appetite |
4 |
3 |
2 |
| Decreased appetite/Anorexia |
1 |
2 |
1 |
* Includes PTs Abdominal (pain, pain upper, pain lower, discomfort,
tenderness, distension) and Stomach discomfort
** Includes PTs Insomnia/Initial insomnia/Middle insomnia/Early morning
awakening |
The overall pattern, and the frequency of adverse events during the longer-term
trials was very similar to that described in Table 3, though several of the
most common events were reported by a greater proportion of patients. Nausea,
for instance, was reported in 40% of patients treated with CHANTIX 1 mg BID
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 clinical trials. The listing does not include those events already listed in the previous tables or elsewhere in labeling, those events for which a drug cause was remote, those events which were so general as to be uninformative, and those events reported only once which did not have a substantial probability of being acutely life-threatening.
BLOOD AND LYMPHATIC SYSTEM DISORDERS Infrequent: Anemia,
Lymphadenopathy. Rare: Leukocytosis, Thrombocytopenia, Splenomegaly.
CARDIAC DISORDERS. Infrequent: Angina pectoris, Arrhythmia,
Bradycardia, Ventricular extrasystoles, Myocardial infarction, Palpitations,
Tachycardia. Rare: Atrial fibrillation, Cardiac flutter, Coronary
artery disease, Cor pulmonale, Acute coronary syndrome.
EAR AND LABYRINTH DISORDERS. Infrequent: Tinnitus, Vertigo
Rare: Deafness, Meniere's disease.
ENDOCRINE DISORDERS. Infrequent: Thyroid gland disorders.
EYE DISORDERS. Infrequent: Conjunctivitis, Dry eye, Eye
irritation, Vision blurred, Visual disturbance, Eye pain. Rare:
Acquired night blindness, Blindness transient, Cataract subcapsular, Ocular
vascular disorder, Photophobia, Vitreous floaters.
GASTROINTESTINAL DISORDERS. Frequent: Diarrhea, Gingivitis
Infrequent: Dysphagia, Enterocolitis, Eructation, Gastritis,
Gastrointestinal hemorrhage, Mouth ulceration, Esophagitis. Rare:
Gastric ulcer, Intestinal obstruction, Pancreatitis acute.
GENERAL DISORDERS AND ADMINISTRATION SITE CONDITIONS. Frequent:
Chest pain, Influenza like illness, Edema, Thirst. Infrequent:
Chest discomfort, Chills, Pyrexia.
HEPATOBILIARY DISORDERS Infrequent: Gall bladder disorder
IMMUNE SYSTEM DISORDERS. Infrequent: Hypersensitivity Rare:
Drug hypersensitivity.
INVESTIGATIONS. Frequent:Liver function test abnormal, Weight
increased. Infrequent: Electrocardiogram abnormal, Muscle enzyme
increased, Urine analysis abnormal.
METABOLISM AND NUTRITION DISORDERS. Infrequent: Diabetes mellitus,
Hyperlipidemia, Hypokalemia. Rare: Hyperkalemia, Hypoglycemia.
MUSCULOSKELETAL AND CONNECTIVE TISSUE DISORDERS. Frequent: Arthralgia,
Back pain, Muscle cramp, Musculoskeletal pain, Myalgia. Infrequent:
Arthritis, Osteoporosis. Rare: Myositis.
NERVOUS SYSTEM DISORDERS. Frequent: Disturbance in attention,
Dizziness, Sensory disturbance. Infrequent: Amnesia, Migraine,
Parosmia, Psychomotor hyperactivity, Restless legs syndrome, Syncope, Tremor.
Rare: Balance disorder, Cerebrovascular accident, Convulsion,
Dysarthria, Facial palsy, Mental impairment, Multiple sclerosis, Nystagmus,
Psychomotor skills impaired, Transient ischemic attack, Visual field defect.
PSYCHIATRIC DISORDERS. Frequent: Anxiety, Depression, Emotional
disorder, Irritability, Restlessness. Infrequent: Aggression,
Agitation, Disorientation, Dissociation, Libido decreased, Mood swings, Thinking
abnormal. Rare: Bradyphrenia, Euphoric mood, Hallucination, Psychotic
disorder, Suicidal ideation.
RENAL AND URINARY DISORDERS. Frequent: Polyuria Infrequent:
Nephrolithiasis, Nocturia, Urine abnormality, Urethral syndrome. Rare:
Renal failure acute, Urinary retention.
REPRODUCTIVE SYSTEM AND BREAST DISORDERS. Frequent: Menstrual disorder
Infrequent: Erectile dysfunction. Rare: Sexual dysfunction.
RESPIRATORY, THORACIC AND MEDIASTINAL DISORDERS. Frequent: Epistaxis,
Respiratory disorders. Infrequent: Asthma. Rare:
Pleurisy, Pulmonary embolism.
SKIN AND SUBCUTANEOUS TISSUE DISORDERS. Frequent: Hyperhidrosis
Infrequent: Acne, Dermatitis, Dry skin, Eczema, Erythema, Psoriasis,
Urticaria. Rare: Photosensitivity reaction.
VASCULAR DISORDERS. Frequent: Hot flush, Hypertension. Infrequent:
Hypotension, Peripheral ischemia, Thrombosis.
Post-Marketing Experience:
The following adverse events have been reported during post-approval use of CHANTIX Because these events are reported voluntarily from a population of uncertain size, it is not possible to reliably estimate their frequency or establish a causal relationship to drug exposure.
There have been reports of depression, mania, psychosis, hallucinations, paranoia,
delusions, homicidal ideation, aggression, hostility, anxiety, and panic, as
well as suicidal ideation, suicide attempt, and completed suicide in patients
attempting to quit smoking while taking CHANTIX (See Boxed
Warning, WARNINGS/Neuropsychiatric Symptoms
and Suicidality, PRECAUTIONS/Information for Patients).
Smoking cessation with or without treatment is associated with nicotine withdrawal
symptoms and the exacerbation of underlying psychiatric illness. Not all patients
had known pre-existing psychiatric illness and not all had discontinued smoking.
There have been reports of hypersensitivity reactions, including angioedema
(See WARNINGS and PRECAUTIONS)
There have also been reports of serious skin reactions, including Stevens Johnson
Syndrome and Erythema Multiforme in patients taking CHANTIX (See WARNINGS
and PRECAUTIONS).
Drug Abuse And Dependence
Controlled Substance Class
Varenicline is not a controlled substance.
Humans: Fewer than 1 out of 1000 patients reported euphoria in
clinical trials with CHANTIX. At higher doses (greater than 2 mg), CHANTIX produced
more frequent reports of gastrointestinal disturbances such as nausea and vomiting.
There is no evidence of dose-escalation to maintain therapeutic effects in clinical
studies, which suggests that tolerance does not develop. Abrupt discontinuation
of CHANTIX was associated with an increase in irritability and sleep disturbances
in up to 3% of patients. This suggests that, in some patients, varenicline may
produce mild physical dependence which is not associated with addiction.
In a human laboratory abuse liability study, a single oral dose of 1 mg varenicline
did not produce any significant positive or negative subjective responses in
smokers. In non-smokers, 1 mg varenicline produced an increase in some positive
subjective effects, but this was accompanied by an increase in negative adverse
effects, especially nausea. A single oral dose of 3 mg varenicline uniformly
produced unpleasant subjective responses in both smokers and non-smokers.
Animals: Studies in rodents have shown that varenicline produces
behavioral responses similar to those produced by nicotine. In rats trained
to discriminate nicotine from saline, varenicline produced full generalization
to the nicotine cue. In self-administration studies, the degree to which varenicline
substitutes for nicotine is dependent upon the requirement of the task. Rats
trained to self-administer nicotine under easy conditions continued to self-administer
varenicline to a degree comparable to that of nicotine, however in a more demanding
task, rats self-administered varenicline to a lesser extent than nicotine. Varenicline
pretreatment also reduced nicotine self-administration.