Form 4 Filing for Alkermes plc: Officer Transaction

This filing details a transaction by David Joseph Gaffin, EVP, CLO of Alkermes, Inc. On April 6, 2026, Mr. Gaffin sold 2,034 ordinary shares of Alkermes plc at a price of $34.57 per share. This sale was executed as part of a Rule 10b5-1 trading plan adopted on November 19, 2025. Following the transaction, Mr. Gaffin owns 233,592 ordinary shares. The filing is made on Form 4 and is signed by Shantale Greenson, acting as attorney-in-fact for Mr. Gaffin.