Aclaris Therapeutics : Overview - September 2021

EMPOWERING PATIENTS THROUGH

KINOME INNOVATION

Company Overview

September 2021

© Copyright 2021 Aclaris Therapeutics, Inc. All rights reserved (PP--US-0618 09/21)

Cautionary Note Regarding Forward-Looking Statements

Any statements contained in this presentation that do not describe historical facts may constitute forward-looking statements as that term is defined in the Private Securities Litigation Reform Act of 1995. These statements may be identified by words such as "believe," "expect," "may," "plan," "potential," "will," and similar expressions, and are based on Aclaris' current beliefs and expectations. These forward-looking statements include expectations regarding Aclaris' development of its drug candidates, including the timing of its clinical trials and regulatory submissions. These statements involve risks and uncertainties that could cause actual results to differ materially from those reflected in such statements. Risks and uncertainties that may cause actual results to differ materially include uncertainties inherent in the conduct of clinical trials, risks and uncertainties associated with preliminary trial results varying from final results, Aclaris' reliance on third parties over which it may not always have full control,

the uncertainty regarding the COVID-19 pandemic including its impact on the timing of Aclaris' regulatory and research

and development activities, and other risks and uncertainties that are described in the Risk Factors section of Aclaris' Annual Report on Form 10-K for the year ended December 31, 2020 and other filings Aclaris makes with the U.S. Securities and Exchange Commission from time to time. These documents are available under the "SEC Filings" page of the "Investors" section of Aclaris' website at http://www.aclaristx.com. Any forward-looking statements speak only as of the date of this presentation and are based on information available to Aclaris as of the date of this presentation, and Aclaris assumes no obligation to, and does not intend to, update any forward-looking statements, whether as a result of new information, future events or otherwise

This presentation also contains estimates and other statistical data made by independent parties and by us relating to market size and other data about our industry. These data involve a number of assumptions and limitations, and you are cautioned not to give undue weight to such estimates. In addition, projections, assumptions and estimates of our future performance and the future performance of the markets in which we operate are necessarily subject to a high degree of uncertainty and risk.

© Copyright 2021 Aclaris Therapeutics, Inc. All rights reserved (PP--US-0618 09/21)

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Biotechnology Company Focused on the Kinome:

People + Platform + Pipeline

LEADERSHIP

Founded and Led by Physicians and Scientists

• World class ex-Pfizer (kinase) and ex-GSK (immunology) leadership
• Kinome experts skilled at developing kinase targeted medicines

KINect®

PLATFORM

Proprietary Kinase

Discovery Engine

• Versatile platform
• Fully integrated discovery and development team
• Advancing small molecule drug candidates designed to parallel or exceed efficacy of high-value biologics

INNOVATIVE PIPELINE

(investigational drug candidates)

ATI-450 - MK2i

• Oral anti-TNFα,anti-IL1, anti- IL6

ATI-1777 - Topical "Soft"

JAK1/3i

• Tissue specific therapy for the potential treatment of moderate to severe atopic dermatitis (AD)

ATI-2138 - ITK/TXK/JAK3i

• Oral dual inhibitor of T-cell and cytokine receptors

Development of Small Molecule Therapeutics for Immuno-inflammatory Diseases

** All trademarks are the property of their respective owners.

© Copyright 2021 Aclaris Therapeutics, Inc. All rights reserved (PP--US-0618 09/21)

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The Kinase Opportunity

Unlocking the Potential of the Kinome

Medically Important and Productive Target Class

Most Members of the Kinome Remain Unexplored

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>60 Marketed Drugs1	518 Members
~$48B2,3	>90% of the Human Kinome
Annual Sales of Kinase Drugs	remains undrugged5

Creating New Medicines Targeting Previously Inaccessible Kinome Targets

1. GoodRx. Accessed July 8, 2021. https://www.goodrx.com/kinase-inhibitors.
2. Data on file.
3. Oprea TI, et al. Unexplored opportunities in the druggable human genome. Nature Rev Drug Discov. Poster Jan. 2017.
4. Manning G, et al. Science. 2002;298(5600):1912-1934.

5. Oprea TI, et al. Nat Rev Drug Discov. 2018;17(5):317-332.	** All trademarks are the property of their respective owners.	4
© Copyright 2021 Aclaris Therapeutics, Inc. All rights reserved (PP--US-0618 09/21)

Experienced R&D Leadership Team

Proven Track Record in Immunology and Inflammation

• Former SVP, R&D at GSK.
• Led discovery and development teams in Immuno-Inflammation and Dermatology leading to multiple successful NDAs, including NUCALA® &
  BENLYSTA®

• Former Executive Director,	• Former VP Research &
Pfizer Inflammation Research	Global Head, Pfizer
and Leader of Global Kinase	Inflammation,
Technology Team	co-leader of Pfizer Licensing
• >95 publications and patents	Team
(>30 total on kinases)	• Delivered 8 clinical
	candidates, 6 INDs and 1
	NDA in inflammation and
	cancer

• Former Research Fellow and Director, Pfizer Chemistry
• >100 publications and patents (15 total on kinases)
• Project Lead for PFE JAK Program

	David Gordon		Joseph Monahan,		Walter Smith		Jon Jacobsen,
		PhD		Scientific & BD		PhD
	Chief Medical Officer
		Chief Scientific Officer		Consultant		VP, Chemistry

• Immunologist/drug discovery leader at pharma (Pfizer & biotech)
• Validated JAK 1/3 as target for transplant/RA/psoriasis, leading to approval of
  XELJANZ®

• Former research project leader at Pfizer. Director of Chemistry at Mnemosyne, Luc, Cadent.
• Inventor of 6 clinical candidates and author of 40 peer reviewed publications and patents

• Former Exec. Director, Pfizer. Site Head for Medicinal & Structural Chemistry.
• >100 patents.
• Co-inventorof multiple drug candidates

Paul Changelian,		David R Anderson,		Gary DeCrescenzo
	PhD Sr. Director,
PhD
	Discovery, Early		SVP, Pharm R&D
VP, Biology
	Development

* All trademarks are the property of their respective owners.

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© Copyright 2021 Aclaris Therapeutics, Inc. All rights reserved (PP--US-0618 09/21)