Daiichi, AstraZeneca Say Nixed Enhertu Probe Foils Patent Policy

Daiichi Sankyo Inc. and AstraZeneca Pharmaceuticals LP have asked US Patent and Trademark Office officials to intervene in their dispute with Seagen Inc., saying the recent rejection of a patent invalidity probe for cancer drug Enhertu runs “squarely contrary” to new guidance on how the Patent Trial and Appeal Board will navigate cases that involve parallel litigation.

“If left uncorrected,” the drugmakers say, the decision to let a jury verdict against them stand as the only authority in the dispute “risks destabilizing the Board’s discretionary‐denial jurisprudence.”

Daiichi and AstraZeneca are asking for the PTAB to rehear their request for ...