Form 4 Filing for Alkermes plc.

David Joseph Gaffin, EVP, CLO of Alkermes, Inc., sold 2,034 ordinary shares on July 6, 2026, at a price of $54.03 per share. This transaction was executed as part of a Rule 10b5-1 trading plan adopted on November 19, 2025. Following the sale, Gaffin owns 227,490 ordinary shares. The filing is a standard Form 4, reporting changes in beneficial ownership of securities.