X0508 4 2024-02-28 0001420565 AILERON THERAPEUTICS INC ALRN 0001007706 VON RICKENBACH JOSEF H C/O AILERON THERAPEUTICS, INC 738 MAIN STREET #398 WALTHAM MA 02451 true false false false false Stock Option (right to buy) 4.80 2024-02-28 4 A false 2725 0.00 A 2034-02-27 Common Stock 2725 2725 D This option was granted on February 28, 2024. The shares underlying the option are scheduled to vest in full on the earlier of (i) February 28, 2025 or (ii) the date of the Issuer's 2024 Annual Meeting of Stockholders. Exhibit 24.1 Power of Attorney /s/ Brian Windsor, attorney-in-fact for Josef H. von Rickenbach 2024-03-01