Gilead defeats immunity bid in hepatitis C patent case

The University of Minnesota had raised three key issue on appeal | Sovereign immunity was at the heart of the years-long dispute.

Gilead Sciences secured a victory at the US Court of Appeals for the Federal Circuit, when the court upheld a decision by the US Patent Trial and Appeal Board (PTAB) invalidating a patent for covering a hepatitis C treatment.

The dispute dates back to 2016 when the University of Minnesota sued Gilead for allegedly infringing the university’s patent by selling drugs containing sofosbuvir.

The suit concerns US patent number 8,815,830, which covers antiviral compounds and methods for using those compounds to treat viral infections, such as that caused by the hepatitis C virus.

Gilead Sciences filed a petition for an inter partes review challenging claims of the ’830 patent directed to phosphoramidate prodrugs of nucleoside derivatives that prevent viruses from reproducing or cancerous tumours from growing.

After this met with success, the Regents of the University of Minnesota appealed the PTAB’s final written decision asserting that claims 1−9, 11−21, and 23−28 of US patent number 8,815,830 are unpatentable as anticipated by the asserted prior art.

Minnesota raised three issues on appeal: that the board erred in holding that the claims do not show a written description of what is claimed in the ’830 patent, and that it ran afoul of requirements set forth in the Administrative Procedure Act (APA). Lastly, Minnesota asserted that it had a sovereign state entity immune from an IPR.

On appeal, the Federal Circuit dismissed the first two issues, finding that the board had not erred.

It also refused to consider the university’s bid for sovereign immunity, pointing out that it was estopped from doing so, because a federal court had already rejected this argument and that the Supreme Court had declined to hear the case.

“Because this issue has been litigated to finality and determined on the merits, Minnesota is collaterally estopped from making an immunity argument here, said the Federal Circuit.”

The court concluded by dismissing all the claims in their entirety and affirming the board’s final written decision.

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