Plavix tops U.S. sales ranks, but not for long

Leave it to a patent expiration to trigger musical chairs at the top of pharma sales rankings. Plavix is now the biggest-selling drug in the U.S., after stealing the crown from Pfizer's ($PFE) newly off-patent Lipitor, PM Live reports. And with other top 5 products facing generic competition, that shuffle will continue.

According to first-quarter data from Drugs.com, the Bristol-Myers Squibb ($BMY) bloodthinner saw U.S. sales grow by almost 3% to $1.62 billion. That trend can't last; Plavix lost exclusivity in May. But until all the second-quarter data comes in Plavix is the reigning prescription drug.

The runners-up for the first quarter are AstraZeneca's ($AZN) stomach drug Nexium, Bristol-Myers' antipsychotic Abilify, Merck's ($MRK) asthma and allergy reliever Singulair; and AZ's Seroquel.

Which drugs are likely to take the top spot? It's certain that Seroquel won't ascend to No. 1; its patent ran out as the first quarter ended. Singulair has a bit longer to enjoy a monopoly, because its exclusivity doesn't run out till August. Nexium and Abilify are the only two among that top 5 whose patents don't run out this year.

As PM Live notes, Lipitor's fall from the top was dramatic: the cholesterol fighter ended the quarter in 14th place with $841 million in sales, surpassed by its own generic copycats, which brought in $950 million. Newly off-patent Zyprexa (Eli Lilly) and Lexapro (Forest Laboratories) also plummeted.

- read the PM Live story

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