Pfizer’s anti-smoking drug in India despite US regulator warnings

Pfizer’s anti-smoking drug in India despite US regulator warnings
Comment E-mail Print Share
First Published: Tue, Mar 11 2008. 12 04 AM IST
Updated: Tue, Mar 11 2008. 12 04 AM IST
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.
The US regulator also cautioned that the drug may cause vivid or strange dreams and affect the patient’s ability to drive or operate machinery.
Indian rules are fuzzy on actions based on such information. The government official responsible for regulating drugs sold in the country, Surinder Singh, the drug controller general of India, or DCGI, could not be reached for comment. Local rules do not mandate patient trials of a drug here if sufficient safety and efficacy data from international studies are produced. The Indian drug regulator gives approval to new drugs if they have been approved by regulators of the US and Europe. No clinical trials were carried out in India in the case of Champix.
Only in specific cases when the safety or efficacy data does not satisfy DCGI are clinical trials asked for but this is always “on a case-to-case basis”, explained a senior official in the DCGI’s office who did not wish to be identified. There is what is called “a pharmacovigilance department to take note of any ADRs (adverse drug reports)” but it is very new and would take time to be fully functional, this official added. Former DCGI M. Venkateswarlu added that there “is always a risk-benefit ratio to a drug. One cannot just keep out a drug especially when it addresses an issue of major public health concern.”
Doctors say that ADRs don’t get adequately reported in India and patients do not have their medical or psychiatric histories mapped, a practice recommended as regular due diligence by FDA and firms such as Pfizer in the US. “No data from India will come up if this drug has side effects,” said Amit K. Mandal, pulmonologist in New Delhi’s Flt Lt Rajan Dhall Hospital run by Fortis Healthcare Ltd.
P.C. Gupta, director of Navi Mumbai’s Healis Sekhsaria Institute for Public Health, said the fact that Champix is a prescription drug limits its risks to some extent. But Mandal is concerned that in India “a six-month-old prescription also gets honoured in a chemist shop.”
Kewal Handa, managing director of Pfizer’s Indian operation, said the need is to balance the benefits of the drug with tightly controlled post-use monitoring of those who take Champix. “The quit rate with Champix is 44%. Compare this to the annual quit rate of smokers in India at 2% when 70% smokers say they want to quit. So there is definitely a need for the drug. We will also be doing a vigorous post-marketing study involving 500 people in the country,” Handa added. The results of Pfizer’s study will be reported to DCGI in six to nine months.
The firm also defends the safety of Champix. “We have put the information up front,” said Anjan Chatterjee, medical director of Pfizer Inc., referring to the product labels. “Smokers in general have higher risk of psychiatric illnesses and breaking an addiction leads to withdrawal symptoms. This is the level playing field with or without Chantix,” he added.
Chatterjee said there has been no scientific evidence linking the drug to suicides. No suicidal tendencies were found in Pfizer’s global trials.
Pfizer is pulling no stops on its Champix marketing campaign in 17 Indian cities—something that worries some doctors that the risks of the drug may get overlooked by consumers. “If the drug is promoted very aggressively to doctors who are not aware of the latest research going on the drug, I’m not sure how it will pan out,” said Vikram Jaggi, medical director at south Delhi-based Asthma, Chest and Allergy Centre, adding that he will prefer to wait for more research on the drug before prescribing it.
But Handa said such concerns are unfounded. “We will be partnering with physicians and corporate hospital chains to set up 600 specialized smoking cessation clinics called Champix Clinics. We are informing the physicians to recognize the risks,” he added. A comprehensive behavioural support programme, called Champs Club, will also be introduced, he said.
Comment E-mail Print Share
First Published: Tue, Mar 11 2008. 12 04 AM IST
More Topics: Pfizer | Anti-smoking drug | Champix | FDA | DCGI |