On August 18, 2023, the Board of Directors of Graphite Bio, Inc. approved the appointment of Kimberlee C. Drapkin as the Company?s President, and as the Company?s principal executive, financial and accounting officer, effective as of August 21, 2023. Ms. Drapkin was appointed to lead the Company?s ongoing exploration of strategic alternatives as part of its corporate restructuring, as announced in February 2023. Kim Drapkin, age 55, has over 25 years of experience working with private and publicly traded biotechnology and pharmaceutical companies, including building and leading finance functions, raising capital, and leading strategic financial planning.

Ms. Drapkin has served on the Board since July 2023. Most recently, Ms. Drapkin was the Chief Financial Officer at Jounce Therapeutics, Inc., a position she held from August 2015 until the company?s acquisition by Concentra Biosciences, LLC in May 2023, playing a key role in building Jounce?s financial infrastructure. Prior to joining Jounce, Ms. Drapkin owned a financial consulting firm where she served as the interim chief financial officer for numerous early-stage biotechnology companies.

Previously, she was the Chief Financial Officer at EPIX Pharmaceuticals, Inc. and also spent ten years in roles of increasing responsibility within the finance organization at Millennium Pharmaceuticals, Inc. Her career began in the technology and life sciences practice at PriceWaterhouseCoopers LLP. Ms. Drapkin served as a member of the board of directors of Proteostasis Therapeutics, Inc. until the completion of the merger of Proteostasis and Yumanity Therapeutics, Inc., at which point she became a member of the Yumanity board of directors. Ms. Drapkin then served on the board of directors of Yumanity through the completion of its reverse merger with Kineta, Inc. She currently serves on the board of directors of Acumen Pharmaceuticals, Inc., Imugene Limited and Kineta, Inc. where she is a member of audit committee at all three companies.

Ms. Drapkin holds a B.S. in accounting from Babson College. The Company entered into a letter agreement, dated August 21, 2023 with Ms. Drapkin. Pursuant to the terms of the Offer Letter, Ms. Drapkin will be entitled to a base salary of $550,000 per year.

In addition, Ms. Drapkin will be entitled to cash severance payments in the amount of $400,000 in the event of a termination of her employment other than for cause or death upon or within 12 months after the closing of a strategic transaction, plus an additional $200,000 if the definitive agreement for such strategic transaction is executed within 3 months after the Start Date or $350,000 in the event of a termination of her employment other than for cause or death upon or within 12 months after the Board?s approval of a plan of dissolution of the Company under Delaware law, in each case subject to Ms. Drapkin?s execution and non-revocation of a separation agreement and release, as further provided in the Offer Letter. For purposes of the Offer Letter, a ?strategic transaction? is defined to includea merger, reorganization or consolidation pursuant to which the holders of the Company?s outstanding voting power and outstanding stock immediately prior to such transaction do not own a majority of the outstanding voting power and outstanding stock or other equity interests of the resulting or successor entity (or its ultimate parent, if applicable) immediately upon completion of such transaction, the sale of all or substantially all of the stock or assets of the Company to an unrelated person, entity or group thereof acting in concert, any other transaction in which the owners of the Company?s outstanding voting power immediately prior to such transaction do not own at least a majority of the outstanding voting power of the Company or any successor entity immediately upon completion of the transaction other than as a result of the acquisition of securities directly from the Company, or any so-called ?reverse merger?

transaction in which the Company effects a business combination with an entity that is not a publicly traded or listed entity and a result of which, the Company remains a publicly traded entity with the equity holders of the other entity owning a substantial portion of the outstanding equity of the ongoing public entity. The foregoing description of the Offer Letter is qualified in its entirety by reference to the full text of the Offer Letter, which the Company intends to file as an exhibit to its Quarterly Report on Form 10-Q for the quarter ending September 30, 2023. Except as set out above, there is no arrangement or understanding between Ms. Drapkin and any other person pursuant to which Ms. Drapkin was appointed as President and Chief Executive Officer.

Furthermore, there are no transactions between Ms. Drapkin (or any member of her immediate family) and the Company that would be required to be reported under Item 404(a) of Regulation S-K. In connection with Ms. Drapkin?s appointments, Josh Lehrer, M.D., the Company?s former President, Chief Executive Officer and member of the Board, separated from his employment and all officer and director positions with the Company, effective as of August 21, 2023. The Company extends its gratitude to Dr. Lehrer for his services and contributions to the Company. Dr. Lehrer will be entitled to the severance benefits applicable to a ?Tier 1 Executive?

under the Company?s Executive Severance Plan and the retention benefits available under a Retention and Severance Agreement, dated March 21, 2023, by and between Dr. Lehrer and the Company.