Last week, the FDA shot down AstraZeneca's ($AZN) bid to stall generic versions of Seroquel. This week, the drugmaker fired back with a lawsuit, seeking an injunction to block Seroquel copies at least until a court can review its claims. The stakes are huge: Seroquel IR's exclusive hold on the market is set to lapse later this month, and it's a multibillion-dollar drug, with $3.3 billion in U.S. sales in 2011.
In its petitions--one covering the original, instant-release version, the other on extended-release Seroquel XR--AstraZeneca claimed the FDA cannot approve generic versions that lacked specific safety warnings required for the branded drug. The thing is, the branded med's warnings rely on trial data that's protected under exclusivity rules, AstraZeneca claims. So, the generic versions can't use that data on their labels. That means there's no way they can offer identical warning language.
Therefore, the company says, the FDA shouldn't be allowed to usher generic Seroquel to the market until Dec. 2, when that data exclusivity expires. "AstraZeneca raised important issues regarding labeling requirements for generic copies of innovative medicines, as well as data exclusivity rights granted to innovative companies that conduct new clinical trials," the company said in a statement, adding that it would "vigorously defend its legal rights."
Obviously, if the drugmaker could delay copycat Seroquel until December, the branded version would have more than 8 additional months to dominate the market. That could translate into $650 million in Seroquel sales otherwise lost to generic competition, give or take a hundred million or so, depending on uptake. We'll soon find out whether a judge thinks the argument is worth pursuing.