X0206 3 2018-11-03 0 0001420565 AILERON THERAPEUTICS INC ALRN 0001709601 Annis Allen C/O AILERON THERAPEUTICS, INC. 490 ARSENAL WAY WATERTOWN MA 02472 0 1 0 0 See Remarks Common Stock 7547 D Stock Option (right to buy) 1.30 2019-06-25 Common Stock 12076 D Stock Option (right to buy) 5.07 2024-03-13 Common Stock 55751 D Stock Option (right to buy) 5.07 2025-03-10 Common Stock 8050 D Stock Option (right to buy) 5.77 2027-03-02 Common Stock 24152 D Stock Option (right to buy) 13.00 2027-07-24 Common Stock 25015 D These options are fully vested. This option was granted on March 10, 2015. The shares underlying the option vested as to 25% of the shares on January 1, 2016 and thereafter are scheduled to vest in equal monthly installments through January 1, 2020. This option was granted on March 2, 2017. The shares underlying the option are scheduled to vest in equal monthly installments through March 2, 2021. This option was granted on July 25, 2017. The shares underlying the option are scheduled to vest in equal monthly installments through July 25, 2021. Exhibit Index: 24.1 Power of Attorney Senior Vice President, Research /s/ Donald Dougherty, attorney-in-fact, for Allen Annis 2018-11-06