Pfizer's Chantix Woes Bash High Hopes

OKLAHOMA CITY -- With Pfizer's(PFE Quote) Chantix stop-smoking aid linked to suicide and other serious side effects, some critics question whether the drug works well enough to justify its risks.

Sales of the drug, once viewed as a surefire blockbuster, have already started to fall. Lately, threats of Chantix-related lawsuits have started to surface as well.

At this point, some experts feel, Pfizer looks worse off than it did when announcing its breakthrough smoking treatment three years ago. After all, the company still remains heavily dependent on Lipitor -- which accounts for almost 30% of its total drug sales -- with generic competition just a few short years away.

Last year, Pfizer had to rely on currency benefits just to muster a 1% increase in revenue. By the first quarter of this year, Pfizer saw its revenue actually fall as patients chose cheaper alternatives to some of its most popular drugs. While sales of the company's newer drugs rocketed almost 80%, sales of its older drugs barely budged at all.

Shares of Pfizer have been in a steady downtrend the past 11 months, losing more than one-third of their value to trade recently at $17.66.

To be fair, Pfizer relied on Chantix for just a fraction of last year's $48.6 billion in overall sales. Still, with patents set to expire on so many of its blockbusters, the company needs all of the bestsellers it can get. Moreover, until recently, Chantix ranked as the company's fastest-growing drug franchise of all.