On July 16 2025, the Court of Appeal dismissed AstraZeneca's appeal and upheld the first instance decision, finding that AstraZeneca's compound patent for dapagliflozin, an SGLT2 inhibitor used to treat diabetes, was invalid for lack of plausibility.
The Court held that the Judge had correctly followed Sandoz v
BMS when concluding that the patent did not make it plausible that
dapagliflozin was an SGLT2 inhibitor with sufficient efficacy to
treat diabetes, as the specification contained only bare
assertions. Although the patent focused on dapagliflozin and
described in general terms an assay to assess an inhibitor's
efficacy, no result was described. This was therefore insufficient
for the skilled person to conclude that dapagliflozin had been
tested in the assay or that it had the necessary inhibitory
activity to be effective. Furthermore, the Court rejected
AstraZeneca's arguments that the standard of plausibility
should be lowered in light of the Enlarged Board of Appeal's
decision in G 2/21, finding that it is not yet possible to
say that the Boards of Appeal or the courts of other EPC
Contracting States have adopted a settled view as to how the test
in G 2/21 is to be interpreted and applied. Therefore, there was no
reason to depart from previous UK case law. The Court went on to
find that even if the standard applicable is whether the skilled
team would have legitimate reason to doubt that dapagliflozin would
be useful for the treatment of diabetes ("ab initio
implausibility"), legitimate reason would have been
found.
The Court also found that the Judge was correct to hold that the
patent did not make a technical contribution over the prior art,
which was very similar to the patent in suit and disclosed a class
of compounds encompassing dapagliflozin. The Court confirmed a
selection from the prior-disclosed genus is only inventive if the
selection makes a technical contribution because the selected
compound in fact has some useful property. Mere plausibility is not
enough for this purpose. It concluded that the Judge's decision
was rightly reached, despite the fact that dapagliflozin had proved
to be successful, and emphasised the lack of basis in the patent in
suit to distinguish dapagliflozin over the class disclosed in the
prior art.
AstraZeneca sought to appeal the decision but was refused permission to appeal by the Supreme Court on 31 July.
Generics (UK) Limited & Ors v AstraZeneca AB [2025] EWCA Civ 903
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