Duncan_Andison /
23 April 2019Americas

Fed Circuit invalidates Purdue oxycodone patent

The Federal Circuit has upheld a finding of the US Patent and Trademark Office (USPTO), which rendered a Purdue Pharma oxycodone patent ineligible.

The USPTO’s Patent Trial and Appeal Board (PTAB) ruled in 2018 that Purdue’s patent for an abuse-deterrent, extended release formulation of oxycodone (US number 9,034,376) was obvious owing to prior art.

The ‘376 patent covers the combination of two gelling agents, polyethylene oxide (PEO) and hydroxypropylmethylcellulose (HPMC), in an oxycodone formulation. It also covers a “controlled release matrix” which provides a therapeutic for 12 hours.

On Wednesday, April 17, the US Court of Appeals for the Federal Circuit upheld the PTAB’s decision, finding that the ‘376 patent was not entitled to priority from a provisional application filed in April 2001.

“Purdue never met its burden to show that the ’376 patent is entitled to claim the benefit of the ’534 application’s filing date”, the ruling said.

The court affirmed the PTAB’s finding that the ‘376 patent’s claims had no written description support in the 2001 provisional application, and were therefore obvious in light of prior art published after that date.

New Jersey-based Amneal Pharmaceuticals had petitioned for inter partes review of the patent, arguing that certain claims of the patent were obvious due to prior art.

Each party was ordered to bear its own costs in the case.

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