Amphastar Pharmaceuticals Inc

Securities Trading Plans of Directors and Executive Officers

During our last fiscal quarter, the following directors and officers, as defined in Rule 16a-1(f), adopted a Rule 10b5-1 trading arrangement, as defined in Regulation S-K Item 408, as follows:

On November 17, 2023, Jacob Liawatidewi, our Executive Vice President of Sales and Marketing and Corporate Administration Center, President of Amphastar France Pharmaceuticals, S.A.S., Corporate Secretary, and Director, adopted a Rule 10b5-1 trading arrangement providing for the sale from time to time of an aggregate of up to 20,533 shares of our common stock. The trading arrangement is intended to satisfy the affirmative defense in Rule 10b5-1(c). The duration of the trading arrangement is until April 1, 2025, or earlier if all transactions under the trading arrangement are completed.

On December 14, 2023, Rong Zhou, our Senior Executive Vice President of Production and President of Amphastar Nanjing Pharmaceuticals, Co., Ltd., adopted a Rule 10b5-1 trading arrangement providing for the sale from time to time of an aggregate of up to 13,893 shares of our common stock. The trading arrangement is intended to satisfy the affirmative defense in Rule 10b5-1(c). The duration of the trading arrangement is until May 17, 2024, or earlier if all transactions under the trading arrangement are completed.

No other officers or directors, as defined in Rule 16a-1(f), adopted orterminated a Rule 10b5-1 trading arrangement, or a non-Rule 10b5-1 trading arrangement, each as defined in Regulation S-K Item 408.