Form 4 Filing for Alkermes plc.

This filing details transactions by Craig C. Hopkinson, EVP R&D, Chief Medical Officer of Alkermes plc. On September 1, 2026, Hopkinson exercised employee stock options for 5,000 ordinary shares at a conversion price of $24.59 per share, acquiring these shares. Concurrently, he acquired these 5,000 shares and subsequently sold 9,000 ordinary shares in a series of transactions at a weighted average price of $46.986, with individual sale prices ranging from $46.8269 to $47.3197. These transactions were executed under Rule 10b5-1 trading plans adopted on March 14, 2025. Following these transactions, Hopkinson directly owns 65,389 ordinary shares.