The PTO’s Patient Trial and Appeal Board said it was not persuaded by Coherus Biosciences’ challenge over the patentability of methods for manufacturing Humira, and ruled in favor of AbbVie in a trial proceeding.

The PTAB denied inter partes review, saying that Coherus did not establish a reasonable likelihood that it would prevail in court. Coherus had argued that some of AbbVie’s claims were not patentable, relating to the development of liquid protein formulations stable enough to be sold as medicine.

The board found that the methods involved in AbbVie’s patent were not obvious at the time of invention, and that a person skilled in the field would not have produced the drug in the same manner under common industry practices, as Coherus had claimed.