Zytiga generics looming as US court nixes J&J patent

Johnson & Johnson has lost another round in its patent defence for prostate cancer blockbuster Zytiga, raising the possibility that generics could launch in the coming days.

A US district court in New Jersey ruled on Friday that a patent which would have provided protection until 2027 was invalid, echoing a decision earlier this year by the United States Patent and Trademark Office (USPTO).

J&J has said it strongly disagrees with the court’s decision and plans to appeal, but the ruling could open the door to generic versions of Zytiga (abiraterone acetate) – which brought in $1.4bn in revenues from the US in the first nine months of the year and is J&J’s biggest product – as early as 31 October.

In a statement, J&J said it has filed a motion for a re-hearing on the disputed patent with the USPTO, and stressed that “commercial launch of generic abiraterone acetate prior to the outcome of the appeals would be considered an at-risk launch.” It says it has patent protection in Europe until 2022.

Several generic drugmakers have submitted copycat Zytiga products for approval by the FDA, and one of these – India’s Sun Pharma – claimed approval for its Yonsa generic in May.

Zytiga sales have been romping away of late in part because of the results of the LATITUDE study in metastatic high-risk castration sensitive prostate cancer, which firmed up its competitive profile against arch rival Xtandi (enzalutamide) from Pfizer.

Analysts have suggested that the new indication could add $1 billion or so to the drug’s sales by 2020, potentially pushing it above the $4 billion mark, so J&J has a lot riding on the outcome of its appeal.

J&J’s chairman Jennifer Taubert suggested on the company’s third-quarter results call that while Zytiga is a great product, growth without it was still upwards of 6% so “we’re absolutely not dependent on it.”

The firm’s chief financial officer Joe Wolk echoed that sentiment on the call, saying that with 12 products that bring in sales above $1 billion a year J&J can “absorb” the impact of early Zytiga generics.

Meanwhile, J&J has been preparing for the loss of market exclusivity for Zytiga by bringing forward a new castration-resistant prostate cancer (CRPC) therapy called Erleada (apalutamide), which was approved in the US in February for an earlier, non-metastatic form of the disease that has not yet spread to other parts of the body.

It hasn’t released any sales figures yet, but says the launch is proceeding as planned as it chases after Xtandi, which is leading the non-metastatic CRPC category at the moment. Other competition could be on the way however, as Bayer just revealed it is planning regulatory filings for its darolutamide rival.