TOKYO, June 12, 2023 – Astellas Pharma Inc. (TSE: 4503, President and CEO: Naoki Okamura, “Astellas”) confirmed the U.S. District Court for the District of Delaware issued a decision on June 9 finding U.S. Patent No. 10,842,780 (the “’780 Patent”, which expires in March 2030) invalid. The ‘780 Patent covers extended-release drug formulations of mirabegron, including Myrbetriq®. This lawsuit was filed by Astellas in the U.S. District Court for the District of Delaware requesting a judgement that certain generic pharmaceutical companies’ proposed generic versions of Myrbetriq® infringe the ’780 Patent. 

Astellas plans to appeal the decision to the United States Court of Appeals for the Federal Circuit (CAFC).

Patents covering crystal forms and methods of using mirabegron, which were the subject of earlier litigation, remain valid and expire in May 2024. Astellas does not anticipate the immediate launch of generic mirabegron.

This decision will have no impact on the financial forecasts of the current fiscal year ending March 31, 2024.


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