Achilles Therapeutics : Corporate Presentation - January 2022

Achilles Therapeutics

Precision T cell therapies to treat solid tumors

January 2022

© Achilles Therapeutics plc 2022

Forward-Looking Statements

This presentation contains express or implied forward-looking statements that are based on our management's belief and assumptions and on information currently available to our management. Although we believe that the expectations reflected in these forward-looking statements are reasonable, these statements relate to future events or our future operational or financial performance, and involve known and unknown risks, uncertainties and other factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by these forward-looking statements.

In some cases, you can identify forward-looking statements by terminology such as "may," "should," "expects," "intends," "plans," "anticipates," "believes," "estimates," "predicts," "potential," "continue," or the negative of these terms or other comparable terminology. These statements are only predictions. You should not place undue reliance on forward-looking statements because they involve known and unknown risks, uncertainties, and other facts, which are, in some cases, beyond our control and which could materially affect results. If one or more of these risks or uncertainties occur, or if our underlying assumptions prove to be incorrect, actual events or results may vary significantly from those implied or projected by the forward-looking statements. No forward-looking statement is a guarantee of future performance. You should read this presentation and the documents that we reference in this presentation completely and with the understanding that our actual future results may be materially different from any future results expressed or implied by these forward-looking statements.

The forward-looking statements in this presentation represent our views as of the date of this presentation. We anticipate that subsequent events and developments will cause our views to change. However, while we may elect to update these forward-looking statements at some point in the future, we have no current intention of doing so except to the extent required by applicable law. You should therefore not rely on these forward-looking statements as representing our views as of any date subsequent to the date of this presentation. This presentation also contains estimates, projections and other information concerning our industry, our business and the markets for our product candidates. Information that is based on estimates, forecasts, projections, market research or similar methodologies is inherently subject to uncertainties and actual events, or circumstances may differ materially from events and circumstances that are assumed in this information. Unless otherwise expressly stated, we obtained this industry, business, market, and other data from our own internal estimates and research as well as from reports, research, surveys, studies, and similar data prepared by market research firms and other third parties, industry, medical and general publications, government data and similar sources. While we are not aware of any misstatements regarding any third-party information presented in this presentation, their estimates, in particular, as they relate to projections, involve numerous assumptions, are subject to risks and uncertainties and are subject to change based on various factors

© Achilles Therapeutics plc 2022	1

Developing precision cell therapy for solid tumors: clonal neoantigen-reactive T cells (cNeT)

Targeting Personalized Clonal Neoantigens, Present on all Tumor Cells

Tumor eradicating potential designed to overcome limitations of current therapies Industry-leading clonal neoantigen discovery using real world patient data (TRACERx) and a proprietary bioinformatics tool (PELEUS®) to enable precision T cell targeting

Targeted and Trackable Precision TIL Therapies

T cell therapy with unprecedented precision and tracking

Addressing multiple patient specific clonal neoantigen targets with T cell therapy tailored to each patient

Differentiated Manufacturing

Scalable commercial manufacturing process designed to be closed and automated

Natural dendritic cell step reduces need for high-doseIL-2, improves T cell fitness, and delivers CD4+/CD8+ T cells targeting multiple clonal neoantigens

Multiple Near-Term Catalysts

Higher-dose cNeT monotherapy patient data in NSCLC and melanoma - 2H 2022 cNeT / PD-1 inhibitor (nivolumab) combination data in melanoma - 2H 2022

Strong Cash Position

$282 million cash balance (as of Sep. 30, 2021) gives cash runway to 1Q 2024

Funds ongoing clinical trials, expanded manufacturing, and additional clinical programs

© Achilles Therapeutics plc 2022

NASDAQ:

ACHL

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Our Management team

Iraj Ali	Sergio Quezada	Karl Peggs
CEO	CSO	CMO

Robert Coutts	Daniel Hood	Ed Samuel
CFO	CLO	SVP Technical Operations

Shree Patel

SVP Clinical Operations

Experiencedleadershipwithdecadesincelltherapydrugdevelopment

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World-renowned directors and advisors

Board of Directors

Edwin Moses	Michael Giordano
Chairman	Non-Executive Director

Carsten Boess	Julie O'Neill
Non-Executive Director	Non-Executive Director

Derek DiRocco	Iraj Ali
Non-Executive Director	Achilles CEO

Scientific Advisory Board

Scott Antonia	Charles Swanton
Chair, Thoracic Oncology	Professor Cancer Medicine

Elizabeth Jaffee	Chris Klebanoff
Deputy Director, Sidney	Head of Immunotherapy
Kimmel Cancer Center	(Breast Division)

Mark Lowdell	Markwin Velders
Director, Centre for Cell,	Former VP Operations and
Gene & Tissue Therapeutics	Managing Director EU

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