Equillium : Corporate Overview

Harnessing Novel Immunobiology

January 2021

www.equilliumbio.com

Safe Harbor Statement

This presentation contains forward-looking statements about Equillium, Inc. (the "Company"). In some cases, you can identify forward-looking statements by the words "will," "expect," "intend," "plan," "objective," "believe," "estimate," "potential," "continue" and "ongoing," or the negative of these terms, or other comparable terminology intended to identify statements about the future. These statements are based on Company management's current beliefs and expectations. These statements include but are not limited to statements regarding the Company's business strategy, the Company's plans to develop and commercialize its product candidates, the safety and efficacy of the Company's product candidates, the Company's plans and expected timing with respect to regulatory filings and approvals, size and growth potential of the markets for the Company's product candidates and cash runway. These statements involve substantial known and unknown risks, uncertainties and other factors that may cause the Company's actual results, levels of activity, performance or achievements to be materially different from the information expressed or implied by these forward-looking statements. The Company may not actually achieve the plans, intentions or expectations disclosed in its forward-looking statements, and you should not place undue reliance on the Company's forward-looking statements.

Actual results or events could differ materially from the plans, intentions and expectations disclosed or implied in the forward- looking statements the Company makes due to the risks and uncertainties inherent in the Company's business, including without limitation, risk described in the Company's filings with the Securities and Exchange Commission ("SEC"). You are cautioned not to place undue reliance on these forward-looking statements, which represent the Company's views as of the date of this presentation. The Company's anticipates that subsequent events and developments will cause the its views to change. However, while the Company may elect to update these forward-looking statements at some point in the future, the Company has no current intention of doing so except to the extent required by applicable law. These and other risks and uncertainties are described more fully under the caption "Risk Factors" and elsewhere in the Company's filings and reports, which may be accessed for free by visiting EDGAR on the SEC web site at http://www.sec.gov. and on the Company's website under the heading "Investors." All forward-looking statements are qualified in their entirety by this cautionary statement. This caution is made under the "safe harbor" provisions of Section 21E of the Private Securities Litigation Reform Act of 1995.

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Novel Treatments for Severe Immuno-inflammatory Disorders

Our mission is to dramatically improve the lives

of patients through the development of novel immunotherapies

Leaders in CD6 biology developing itolizumab, a first-in-classanti-CD6antibody targeting the CD6-ALCAM pathway

Itolizumab is a validated therapeutic with differentiated mechanism of action (MoA) inhibiting the activity and trafficking of Teff

We are advancing development in three severe autoimmune

and inflammatory⎼disorders

⎼ Acute Graft-versus-Host Disease (aGVHD)

⎼ Lupus/Lupus Nephritis

Uncontrolled Asthma

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Pipeline in a Product: Broad Therapeutic Potential of Itolizumab

T Cell Mediated Immuno-inflammatory Diseases

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