X0306 4 2021-08-27 0 0001785345 Landos Biopharma, Inc. LABP 0001844296 Xontogeny, LLC 51 ASTOR PLACE, 10TH FLOOR NEW YORK NY 10003 1 0 0 0 Stock Option (Right to Buy) 14.18 2021-08-27 4 A 0 10709 0.00 A 2031-08-26 Common stock 10709 10709 I See footnotes The shares of common stock underlying this option will vest and become exercisable in 36 equal monthly installments beginning on August 27, 2021, subject to the Fred Callori's continuous service with the Issuer on each such date. Consists of a proportionate interest in stock options awarded to Mr. Callori in connection with his role as a member of the Issuer's Board of Directors. Mr. Callori serves as an officer of Xontogeny, LLC. Xontogeny may be deemed to have an indirect pecuniary interest in the securities reported herein because Xontogeny has the right to receive the director compensation provided in respect of Mr. Callori's board service through a partial management fee offset. Christoph Garabedian is the Chief Executive Officer of Xontogeny. Each of the Reporting Persons disclaims, for purposes of Section 16 of the Securities Exchange Act of 1934, beneficial ownership of such securities, except to the extent of his/its indirect pecuniary interest therein, and this report shall not be deemed an admission that any of the Reporting Persons is the beneficial owner of such securities for purposes of Section 16 or for any other purposes. /s/ Christopher Garabedian for Xontogeny, LLC, By: Christoph Garabedian, its Chief Executive Officer 2021-08-31