X0206 3 2017-06-28 0 0001420565 AILERON THERAPEUTICS INC ALRN 0000889131 ROCHE HOLDING LTD GRENZACHERSTRASSE 122 BASEL V8 CH4070 SWITZERLAND 0 0 1 0 0001053942 ROCHE FINANCE LTD GRENZACHERSTRASSE 124 BASEL V8 CH4070 SWITZERLAND 0 0 1 0 Series D Preferred Stock Common Stock 341238 D Series E-2 Preferred Stock Common Stock 74043 D Series E-3 Preferred Stock Common Stock 64224 D Series F Preferred Stock Common Stock 99586 D The Series D Preferred Stock is convertible into Common Stock on a 9.937-for-one basis into the number of shares of Common Stock shown in column 3 at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The shares have no expiration date. The Series E-2 Preferred Stock is convertible into Common Stock on a 9.937-for-one basis into the number of shares of Common Stock shown in column 3 at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The shares have no expiration date. The Series E-2 Preferred Stock is convertible into Common Stock on a 9.937-for-one basis into the number of shares of Common Stock shown in column 3 at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The shares have no expiration date. The Series F Preferred Stock is convertible into Common Stock on a 9.937-for-one basis into the number of shares of Common Stock shown in column 3 at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The shares have no expiration date. Roche Finance Ltd is the direct beneficial owner of these securities of the Issuer. Roche Finance Ltd is a wholly owned subsidiary of Roche Holding Ltd. Roche Holding Ltd is the indirect beneficial owner of these securities of the Issuer. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of its pecuniary interest therein, if any. Each Reporting Person also disclaims beneficial ownership of any securities of the Issuer that may be or are beneficially owned by any other person or persons other than such Reporting Person. This Form 3 shall not be deemed an admission that any Reporting Person or other person is a beneficial owner of any securities of the Issuer for any purpose, other than the securities reported in this Form 3. /s/ Dr. Beat Kraehenmann 2017-06-28 /s/ Dr. Urs Jaisli 2017-06-28