Korro Bio : Q1’24 Corporate Presentation

Disclaimers

Forward-Looking Statements

Certain statements in this presentation may constitute "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995, as amended. Forward-looking statements include, but are not limited to, express or implied statements regarding expectations, hopes, beliefs, intentions or strategies of Korro Bio, Inc. (Korro) regarding the future including, without limitation, express or implied statements regarding: Korro's planned regulatory filing for KRRO-110 in AATD and any interim data readout; Korro's cash runway; Korro's ability to advance its pipeline and the role of RNA editing technology in developing therapeutic options; KRRO-110's potential as a best-in-class drug candidate for AATD; the benefits of OPERA; the expected size of the offering; and our use of proceeds from this offering, estimates of our expenses, capital requirements and needs for additional financing; among others. In addition, any statements that refer to projections, forecasts, or other characterizations of future events or circumstances, including any underlying assumptions, are forward-looking statements. The words "anticipate," "believe," "continue," "could," "estimate," "expect," "intend," "may," "might," "plan," "possible," "potential," "predict," "project," "should," "strive," "would," "aim," "target," "commit," and similar expressions may identify forward-looking statements, but the absence of these words does not mean that statement is not forward looking. Forward-looking statements are based on current expectations and assumptions that, while considered reasonable are inherently uncertain. New risks and uncertainties may emerge from time to time, and it is not possible to predict all risks and uncertainties. Factors that may cause actual results to differ materially from current expectations include, but are not limited to, various factors beyond management's control including risks inherent in biopharmaceutical development; risks associated with pre-clinical studies and clinical trials; and other risks associated with obtaining regulatory approvals and protecting intellectual property; as well as risks associated with general economic conditions; the inability to recognize the anticipated benefits of the recently completed merger, which may be affected by, among other things, competition, Korro's ability to grow and manage growth profitably, maintain relationships with customers and suppliers and retain key employees; the possibility that Korro may be adversely affected by other economic, business, and/or competitive factors; other risks and uncertainties indicated from time to time in Korro's filings with the SEC, including Item 1A. "Risk Factors" in Korro's Quarterly Report on Form 10-Q filed with the SEC on May 14, 2024, as such may be amended or supplemented by its other filings with the SEC. Nothing in this presentation should be regarded as a Part II representation by any person that the forward-looking statements set forth herein will be achieved or that any of the contemplated results of such forward-looking statements will be achieved. You should not place undue reliance on forward-looking statements in this presentation, which speak only as of the date they are made and are qualified in their entirety by reference to the cautionary statements herein. Except as required by law, Korro does not undertake or accept any duty to release publicly any updates or revisions to any forward-looking statements to reflect any change in their expectations or in the events, conditions or circumstances on which any such statement is based. This presentation does not purport to summarize all of the conditions, risks and other attributes of an investment in Korro.

Industry and Market Data

Certain information contained in this presentation relates to or is based on studies, publications, surveys and Korro's own internal estimates and research. In this presentation, Korro relies on, and refers to, publicly available information and statistics regarding market participants in the sector in which Korro competes and other industry data. Any comparison of Korro to any other entity assumes the reliability of the information available to Korro. Korro obtained this information and statistics from third-party sources, including reports by market research firms and company filings. In addition, all of the market data included in this presentation involve a number of assumptions and limitations, and there can be no guarantee as to the accuracy or reliability of such assumptions. Finally, while Korro believes its internal research is reliable, such research has not been verified by any independent source and Korro has not independently verified the information.

Trademarks

This presentation may contain trademarks, service marks, trade names and copyrights of other companies, which are the property of their respective owners. Solely for convenience, some of the trademarks, service marks, trade names and copyrights referred to in this presentation may be listed without the TM, SM © or ® symbols, but Korro will assert, to the fullest extent under applicable law, the rights of the applicable owners, if any, to these trademarks, service marks, trade names and copyrights.

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Create Transformative Genetic Medicines

for Diseases with High Prevalence

A transient and reversible way to edit RNA (A-to-I edit) using an endogenous "editor"

Expanding the genetic medicines tool-kit by providing an "activation" approach

Key internal discoveries driving the potential to develop multiple drug candidates

Initial focus on unique opportunities in rare liver and CNS indications

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Causal Missense Variants Have Been Identified in Both Rare and Common Diseases

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Need for an approach to transiently edit variants to modify biology and alleviate pathology

OPERA: Our Differentiated Approach for RNA Editing

Comprehensive IP portfolio with 32 patent families1 covering

Korro platform technology and editing strategies

OPERA: Our Approach

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