Alpine Immune Sciences : Corporate Presentation – January 2021

Leading the Next Evolution of Immunotherapies

January 2021

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Forward Looking Statements

This presentation contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, Section 21E of the Securities Exchange Act of 1934 and the Private Securities Litigation Reform Act of 1995. These forward- looking statements are not based on historical fact and include statements regarding Alpine's platform technology, potential therapies, potential milestone and royalty payments, future development plans, clinical and regulatory objectives and the timing thereof, expectations regarding the sufficiency of cash to fund operations through 2024, expectations regarding the plans of its collaborators, expectations of future collaborations, and expectations regarding the potential efficacy and commercial potential of Alpine's and its collaborator's product candidates. Forward-looking statements generally include statements that are predictive in nature and depend upon or refer to future events or conditions, and include words such as "may", "will", "should", "would", "expect", "plan", "intend", and other similar expressions among others. These forward-looking statements are based on current assumptions involving risks, uncertainties, and other factors that may cause actual results, events, or developments to be materially different from those expressed or implied by such forward-looking statements. These risks and uncertainties, many of which are beyond our control, include, but are not limited to: Alpine's programs may not advance into the clinic or result in approved products on a timely or cost-effective basis or at all; Alpine may not achieve additional milestone payments pursuant to its collaborations; the impact of competition; adverse conditions in the general domestic and global economic markets; as well as the other risks identified in our filings with the Securities and Exchange Commission. These forward-looking statements speak only as of the date hereof, Alpine undertakes no obligation to update forward-looking statements, and readers are cautioned not to place undue reliance on such forward-looking statements.

"Variant Immunoglobulin Domain", "vIgD", "Transmembrane Immunomodulatory Protein", "TIP", "Secreted Immunomodulatory Protein", and "SIP" are registered trademarks or trademarks of Alpine Immune Sciences, Inc. in various jurisdictions.

All rights reserved.

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Leading the Next

Evolution of

Immunotherapies

With a Highly Productive

Directed Evolution

Platform

ALPN-101

Dual Costimulation

Antagonist

Systemic Lupus

Erythematosus

Partnered with

Phase 2

In Preparation

ALPN-202

Conditional CD28

Costimulator and Dual

Checkpoint Inhibitor

Immuno-oncology

Phase 1

Advanced

Malignancies

ALPN-303

Dual B Cell

Cytokine Antagonist

1. Cell-MediatedInflammatory Diseases

Phase 1

Start Targeted 2021

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ALPN-101

Autoimmune/Inflammatory Diseases:

Dual CD28/ICOS Antagonist

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