Alkermes plc

During the three months ended March 31, 2025, the following officers (as defined in Rule 16a-1(f) under the Exchange Act) and directors of the Company adopted or terminated contracts, instructions or written plans for the purchase or sale of the Company’s securities that are or were intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) under the Exchange Act (each, a “Rule 10b5-1 plan”) as follows: (i) on February 14, 2025, Craig Hopkinson, M.D., our Executive Vice President, Research and Development and Chief Medical Officer, terminated a Rule 10b5-1 plan that provided for the sale of up to 820,467 ordinary shares of the Company and was scheduled to expire on July 31, 2025; (ii) on February 27, 2025, Shane Cooke, adirector, adopted a Rule 10b5-1 plan providing for the sale of up to 61,200 ordinary shares of the Company that may be obtained from the exercise of vested stock options; this plan is scheduled to expire on February 27, 2026; (iii) on March 10, 2025, Christian Todd Nichols, our Senior Vice President Chief Commercial Officer, adopted a Rule 10b5-1 plan providing for the sale of up to 6,667 ordinary shares of the Company; this plan is scheduled to expire on December 9, 2025; and (iv) on March 14, 2025, Craig Hopkinson, M.D., our Executive Vice President, Research and Development and Chief Medical Officer, adopted a Rule 10b5-1 plan providing for the sale of up to 108,000 ordinary shares of the Company (including shares that may be obtained from the exercise of vested stock options); this plan is scheduled to expire on September 30, 2026. During the three months ended March 31, 2025, no other officers or directors of the Company adopted, modified orterminated a Rule 10b5-1 plan or a trading plan not intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) under the Exchange Act.