On April 7, 2021, the European Patent Office (EPO) Opposition Division (OD) issued a comprehensive written decision in the Opposition by Gilead Sciences, Inc. against NuCana plc’s European Patent No. B-2 955 190, upholding amended compound claims that include Gilead’s blockbuster hepatitis C drug, Sovaldi (sofosbuvir). The claims were upheld over various arguments made by Gilead, including an assertion that the NuCana patent did not teach the skilled worker how to make the nucleoside component of Sovaldi (which is a nucleotide phosphoramidate). Gilead alleged, as it did in the myriad of global Idenix litigation cases, that a skilled person in 2003 who tried to make the nucleoside of Sovaldi “would be required to undertake extensive experimentation, if indeed he would be able to succeed at all. This represented an undue burden.”

Full Article Available Here