Prime Medicine, Inc.

Forward Looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, implied and express statements about Prime Medicine’s beliefs and expectations regarding: the significance of data from its Phase 1/2 trial of PM359 on other pipeline programs and Prime Editing; the planned regulatory interactions with the FDA based on the data from its Phase 1/2 trial of PM359 and the outcomes of any such interactions; its evaluation of strategic alternatives and potential partnership opportunities for PM359, including its ability to execute and realize the anticipated benefits of any strategic alternatives it may pursue; the agreement with the CF Foundation, its expanded funding pursuant thereto, and the intended and potential benefits thereof, including the receipt of payments based on scientific milestones; the continued advancement of PASSIGE-based approaches for correcting CF mutations other than G542X; the continued development and advancement of its AATD and Wilson’s Disease programs, including the timing of initial clinical data for both programs in 2027; the initiation, timing, progress, and results of its research and development programs, preclinical studies and future clinical trials, including the release of data related thereto; the potential of Prime Editing to correct the causative mutations of, and to cure, diseases, including AATD, Wilson’s Disease, CF and CGD; its expectations regarding the anticipated benefits of its May 2025 strategic restructuring and reduction in force and its ability to implement and achieve the expected cost savings in connection therewith; its expectations regarding the breadth of Prime Editing technology and the implementation of its strategic plans for its business, programs, and technology; the potential of Prime Editing to unlock opportunities across thousands of potential indications; and its expected cash runway.

Any forward-looking statements in this press release are based on management’s current expectations and beliefs and are subject to a number of risks, uncertainties and important factors that may cause actual events or results to differ materially from those expressed or implied by any forward-looking statements contained in this press release, including, without limitation, risks associated with: uncertainties related to Prime Medicine’s product candidates entering clinical trials; the authorization, initiation, and conduct of preclinical and IND-enabling studies and other development requirements for potential product candidates, including uncertainties related to opening INDs and obtaining regulatory approvals; risks related to the development and optimization of new technologies, the results of preclinical studies, or clinical studies not being predictive of future results in connection with future studies; the scope of protection Prime Medicine is able to establish and maintain for intellectual property rights covering its Prime Editing technology; Prime Medicine’s ability to identify and enter into future license agreements and collaborations; Prime Medicine’s expectations regarding the anticipated timeline of its cash runway and future financial performance; and general economic, industry and market conditions. These and other risks and uncertainties are described in greater detail in the section entitled “Risk Factors” in Prime Medicine’s most recent Annual Report on Form 10-K, as well as any subsequent filings with the Securities and Exchange Commission. In addition, any forward-looking statements represent Prime Medicine’s views only as of today and should not be relied upon as representing its views as of any subsequent date. Prime Medicine explicitly disclaims any obligation to update any forward-looking statements subject to any obligations under applicable law. No representations or warranties (expressed or implied) are made about the accuracy of any such forward-looking statements.