X0206 3 2019-04-02 0 0001420565 AILERON THERAPEUTICS INC ALRN 0001315797 Satter Muneer A C/O SATTER MANAGEMENT CO., L.P. 676 NORTH MICHIGAN AVENUE, SUITE 4000 CHICAGO IL 60611 0 0 1 1 See Remarks Common Stock 3909449 I See footnote Warrants (right to buy) 2.00 2019-04-02 2024-04-02 Common Stock 3731343 I See footnote Reflects 3,731,343 shares of common stock and associated warrants to purchase 3,731,343 shares of common stock purchased in a private placement by Satter Medical Technology Partners, L.P. ("SMTP") on April 2, 2019. The amount in Column 4 includes (a) 161,440 shares that are held by the Muneer A. Satter Revocable Trust for which the Reporting Person serves as trustee and, in such capacity, has sole voting and dispositive power over all such shares, (b) 16,666 shares that are held by various other trusts and other entities for which the Reporting Person serves as trustee, investment advisor or manager and, in such capacity, has sole voting and dispositive power over all such shares, and (c) the remaining balance of shares are held by SMTP for which the Reporting Person has sole voting and dispositive power over all such shares. The Reporting Person disclaims beneficial ownership of all shares included in clauses (b) and (c) of this footnote (2), except to the extent of his pecuniary interest. Warrants are held by SMTP for which the Reporting Person has sole voting and dispositive power over all such warrants and the underlying shares of common stock. The Reporting Person disclaims beneficial ownership of all warrants and underlying shares of common stock, except to the extent of his pecuniary interest. In connection with the transaction, SMTP had a contractual right to designate one member of the Board of Directors of Aileron Therapeutics, Inc. Therefore, the Reporting Person may be deemed to be a director by deputization. Exhibit 24: Power of Attorney /s/ Robert M. Hayward, P.C., by Power of Attorney 2019-04-03