Johnson & Johnson down to its final Zytiga defenses as judge puts temporary kibosh on generics

Zytiga copycats may be revving up for launches later this week, thanks to a brand-new patent ruling. But Johnson & Johnson isn't giving up the fight for its prostate cancer blockbuster—and the 71% growth it has turned in so far this year.

U.S. District Judge Kevin McNulty on Friday invalidated a key patent protecting Zytiga, one of the leading prostate cancer therapies on the market. But as J&J made clear it wasn't giving up the fight, McNulty also ordered generics makers to hold off on their launches until at least Wednesday.

In a statement, the company said it “strongly disagrees” with the ruling, and it is asking the court for an injunction against those launches until its appeal can be heard.

Zytiga has been driving growth for J&J ever since its launch back in 2011 took off faster than pharma watchers expected, and even now, its sales are leaping ahead. Propelled by strong data and a label expansion to treat metastatic high-risk castration-sensitive prostate cancer, Zytiga generated $1.42 billion in the U.S. in the first nine months of 2018, a 71% boost year over year.

But as generic competition looms, J&J executives insist they don't need Zytiga to keep sales growth coming. On the company’s third-quarter conference call, they said the company has a broad pharma portfolio that turned in 8.2% growth excluding currency effects; without Zytiga, the unit still grew by 6.6%.

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Plus, Zytiga's international growth can help soften the blow. Internationally, the drug posted sales of $1.29 billion through the first nine months of this year, a 40% increase, and Zytiga boasts patent protections in Europe until 2027, J&J said.

Meanwhile, J&J has pinned new hopes on its follow-up prostate cancer drug Erleada. But cheap Zytiga generics could undercut that drug and another rival in the disease area, Pfizer's Xtandi. J&J hasn't yet released sales figures for Erleada.

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The latest ruling followed another loss for Zytiga at the start of this year, when the U.S. Patent Trial and Appeals Board invalidated a patent on the drug. At the time, an analyst wrote that he expected Zytiga generics to make their debut this month, after the expiration of a 30-month stay mandated by the Hatch-Waxman Act.

Amneal and Wockhardt have tentative FDA approvals for their generics, according to the FDA's website.