New Delhi: Doctors and experts have expressed concern over an anti-smoking drug, manufactured and marketed by the world’s largest drug maker Pfizer Inc., being launched in India barely a month after the US health regulator issued safety warnings and said it was continuing investigation whether the drug triggers mood changes and, in some instances, suicides.
Pfizer Ltd, the Indian unit of the US pharmaceutical giant, which has launched the drug varenicline sold as Champix in India (it is branded Chantix in the US), says the drug has proven therapeutic value. It is a prescription drug that will be promoted only through doctors who will be informed of its risks carried in its labelling, the company insists, adding that it will carry out detailed post-marketing surveillance on the drug.
The introduction of the drug comes at a time when concerns over smoking and tobacco use—some 200 million Indians smoke—are being voiced by policymakers and health researchers. According to a recent study published in The New England Journal of Medicine, smoking will cause 930,000 adult deaths in 2010 in India and given the growth in population, there will be a million smoking-associated deaths every year thereafter.
Randeep Guleria, a professor of medicine specializing in pulmonary care at New Delhi’s All India Institute of Medical Sciences, calls smoking, which causes 10 kinds of cancer, the “single largest cause of preventable death.”
That sets the perfect stage for a drug such as Champix, although, at Rs9,500 for the three-month treatment, it doesn’t come cheap. Two studies have shown that 44% of smokers who went through the prescribed 12-week treatment quit smoking.
A non-nicotine smoking cessation drug—the first one to be approved in 10 years by the Food and Drug Administration (FDA), the US regulator for the pharmaceutical industry—Champix acts on the same brain receptors as nicotine and simultaneously reduces withdrawal symptoms as well as the pleasure of smoking. First approved by FDA in May 2006, the drug is expected to turn in revenues of more than $1 billion (Rs4,000 crore) this year. It has received a patent in India.
Yet, the drug carries potentially high risks. FDA first sounded the alarm last November by announcing that it was “evaluating adverse event reports on Chantix related to changes in behaviour, agitation, depressed mood, suicidal thoughts, attempted and completed suicide”.
On 1 February, FDA issued new safety warnings on the drug. By then, it had received information on 491 cases of “suicidal ideation” with 37 instances of actual suicides.
“As FDA continues its review of the adverse event reports, it appears increasingly likely that there may be an association between Chantix and serious mood and behaviour symptoms,” the regulator said in a statement on its website, adding that Pfizer had been asked to display the safety information more prominently on the drug’s label.