What is CHAMPIX?
CHAMPIX is a tablet containing the active substance varenicline . The 0.5 mg tablets are white, the 1 mg tablets are light blue.
Deepening: Varenicline to quit smoking
What is CHAMPIX used for?
CHAMPIX is indicated for smoking cessation in adults. The medicine can only be obtained with a prescription.
How is CHAMPIX used?
CHAMPIX should be used by patients who are motivated to stop smoking and who receive additional and supportive advice. The patient must first establish a date to quit smoking. Treatment with CHAMPIX should start 1-2 weeks before this date. The patient takes one 0.5 mg tablet a day for 3 days, then one 0.5 mg tablet twice a day for another 4 days. From this moment and until the end of the treatment (12 weeks) the patient takes one 1 mg tablet twice a day. At the beginning of the treatment a particular package is provided, including the correct quantities of both tablet doses. In patients who do not tolerate the 1 mg dose twice a day it can be reduced to 0.5 mg twice a day. Patients who have severe kidney problems should take CHAMPIX (1 mg) once a day.
After 12 weeks of treatment, if the patient has stopped smoking, the doctor may decide to
continue treatment for a further 12-week cycle. He can also decide to gradually stop the administration of the medicine ("tapering").
The tablets should be swallowed whole with water. They can be taken on a full or empty stomach.
How does CHAMPIX work?
People who smoke acquire an addiction to nicotine, a chemical contained in tobacco. Nicotine acts on the nervous system, where it binds to receptors and triggers the release of a chemical transmitter, dopamine, which plays an important role as a "messenger" of the pleasure derived from smoking. The active substance in CHAMPIX, varenicline, can bind to some of these receptors, the acetylcholine α4β2 receptor receptors. By binding to these receptors, it acts in two ways: on the one hand, it performs a function similar to nicotine (partial agonist activity), thus helping to alleviate the symptoms of compulsive cravings, and on the other hand it hinders the nicotinic bond (antagonistic activity ), replacing nicotine and reducing the effects of smoking-related pleasure.
What studies have been carried out on CHAMPIX?
The effects of CHAMPIX were first tested in experimental models before being studied in humans. The two main studies on the efficacy of CHAMPIX in smoking cessation involved 2 052 patients (average age: 43 years), who underwent one of the following three treatments for 12 weeks: CHAMPIX, bupropion (another drug no nicotine used to stop smoking) or placebo (fictitious substance). The patients were then monitored for another 40 weeks to record any relapses. The main criterion chosen to measure efficacy was the number of patients who had completely abstained from smoking for 4 weeks (between the 9th and 12th week of study), a fact this proved by laboratory tests of expired air aimed at identify the presence of smoke.
What benefit has CHAMPIX shown during the studies?
In both studies CHAMPIX was more effective than bupropion or placebo in helping patients to stop smoking. The percentage of patients who completely abstained from smoking during the 9th-12th week was 44% with CHAMPIX, 30% with bupropion and 18% with placebo. The number of patients who continued not to smoke after CHAMPIX treatment is superior to the subjects belonging to the placebo group: 40 weeks after the end of the treatment, the percentage of patients without relapses was 23% among those who had taken CHAMPIX and 9% among those who had taken a placebo. In the group of subjects treated with bupropion it was instead of 16%.
What are the risks associated with CHAMPIX?
The most common side effects (seen in more than 1 patient in 10) are nausea, insomnia, alteration of dream activity (dreams) and headache. For the full list of all side effects reported with CHAMPIX, see the Package Leaflet.
CHAMPIX should not be used in people who may be hypersensitive (allergic) to varenicline or any of the other ingredients.
Why has CHAMPIX been approved?
The Committee for Medicinal Products for Human Use (CHMP) concluded that CHAMPIX was effective in helping patients to stop smoking and pointed out that the risks associated with smoking outweigh those associated with using the drug. The CHMP has therefore recommended that it be given marketing authorization.
What measures are being taken to ensure the safe use of CHAMPIX?
Since the studies carried out on CHAMPIX do not include some groups of patients (such as older people, patients suffering from heart diseases or lungs and other diseases), the manufacturing company will carry out further studies and monitor the use of the drug by these patients, to ensure proper detection of any side effects.
Other information on CHAMPIX:
On 26 September 2006, the European Commission granted a marketing authorization for CHAMPIX, valid throughout the European Union, to Pfizer Limited. For the full version of the evaluation (EPAR) of CHAMPIX, click here.
Last update of this summary: 08-2006
