AnaptysBio : Corporate Presentation September 2021

Corporate Overview

September 2021

Nasdaq: ANAB

Safe Harbor Statement

This presentation and any accompanying oral presentation contain "forward‐looking" statements within the meaning of the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995, including, but not limited to: the timing of the release of data from our clinical trials, including imsidolimab's Phase 2 trials in acne, hidradenitis suppurativa, EGFRi/MEKi skin toxicity and ichthyosis, rosnilimab's Phase 1 trial in healthy volunteers and ANB032's Phase 1 trial in healthy volunteers; the timing of initiation of

imsidolimab's Phase 3 trial in GPP and rosnilimab's Phase 2 trial in alopecia areata; the timing of presentation of GPP Phase 2 data at a medical conference; the milestones and success of our GSK collaboration, including timing of milestone and royalty payments; and our projected 2021 cash burn and cash runway. Statements including words such as "plan," "continue," "expect," or "ongoing" and statements in the future tense are forward-looking statements. These forward-looking statements involve risks and uncertainties, as well as assumptions, which, if they do not fully materialize or prove incorrect, could cause our results to differ materially from those expressed or implied by such forward-looking statements. Forward-looking statements are subject to risks and uncertainties that may cause the company's actual activities or results to differ significantly from those expressed in any forward-looking statement, including risks and uncertainties related to the company's ability to advance its product candidates, obtain regulatory approval of and ultimately commercialize its product candidates, the timing and results of preclinical and clinical trials, the company's ability to fund development activities and achieve development goals, the company's ability to protect intellectual property and other risks and uncertainties described under the heading "Risk Factors" in documents the company files from time to time with the Securities and Exchange Commission. These forward-looking statements speak only as of the date of this presentation, and the company undertakes no obligation to revise or update any forward-looking statements to reflect events or circumstances after the date hereof.

Certain information contained in this presentation may be derived from information provided by industry sources. The Company believes such information is accurate and that the sources from which it has been obtained are reliable. However, the Company cannot guarantee the accuracy of, and has not independently verified, such information.

The trademarks included herein are the property of the owners thereof and are used for reference purposes only. Such use should not be construed as an endorsement of such products.

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AnaptysBio: Clinical-Stage Novel Antibody R&D Engine

Advancing First-In-Class Immunology Therapeutics to Patients

Wholly-Owned Clinical Catalysts

Dermatology Breadth

Pipeline Expansion

Validated Platform

Accelerating

Partnership Revenues

Capital Efficient

Business Model

Multiple imsidolimab Phase 2 readouts anticipated over upcoming 18 months, in addition to advancement of imsidolimab into GPP Phase 3 trials

6 immuno-dermatology clinical indications under Phase 2/3 development during 2021

Deep preclinical pipeline focused on first-in-class inflammation and immuno- oncology mechanisms with a goal of advancing 1 new program to IND or equivalent each year

Rapid antibody R&D engine has advanced 8 internally-generated antibodies to clinical development since 2016

Approximately $200MM in partnership revenues to date, earning royalties on JEMPERLITM (dostarlimab) and ZejulaTM (niraparib)

Cash and existing partnerships anticipated to extend runway into 2024, $396MM in cash (end Q2 2021) with projected 2021 net burn less than $100MM

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Wholly-Owned Product Pipeline

6 Immuno-Dermatology Indications Under Phase 2/3 Development During 2021

Antibody

Program

Imsidolimab

(ANB019):

Anti-IL-36R

Rosnilimab

(ANB030):

Anti-PD-1

Agonist

ANB032: Anti- BTLA Modulator

Therapeutic			Development Stage & Anticipated Milestones
Indication	Discovery	Preclinical	Phase 1	Phase 2	Phase 3
Generalized				GALLOP: Phase 2 Data To Be Presented At	Phase 3 Initiation Anticipated
Pustular Psoriasis				EADV Congress on October 2nd 2021	Q3 2021
Palmoplantar				POPLAR: Phase 2 Top-Line Data Announced March 2021
Pustulosis				No Further Clinical Development Currently Planned
Acne Vulgaris				ACORN: Phase 2 Initiated Q2 2021
		Phase 1 Data	Topline Data Anticipated H1 2022
			Presented at
Hidradenitis			EAACI 2018	HARP: Phase 2 Initiated Q2 2021
Suppurativa				Topline Data Anticipated H2 2022
EGFRi-Mediated				EMERGE: Interim Analysis Anticipated End 2021
Skin Toxicity
Ichthyosis				INSPIRE: Topline Phase 2 Data Anticipated 2022
Alopecia Areata			Phase 1 Top-Line
		Data Anticipated	Phase 2 Initiation Anticipated in Q4 2021
			Q4 2021
Inflammatory			Topline Phase 1
		Data Anticipated
Diseases
		H1 2022

All programs generated internally using AnaptysBio's

proprietary antibody platform technology

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Partnered Product Pipeline

Earning Royalties on JEMPERLITM and ZejulaTM Starting 2021

Antibody Program	Therapeutic				Development Stage & Anticipated Milestones			Commercial
Indication	Discovery	Preclinical	Phase 1	Phase 2	Phase 3	Marketed	Rights

dMMR Endometrial

Cancer

JEMPERLI

(dostarlimab): dMMR Pan-Tumor

Anti-PD-1 Antagonist

US BLA and EU MAA Approved April 2021

US BLA Approved

August 2021

	Ovarian Cancer		OPAL: Ongoing	FIRST: Ongoing
	NSCLC		PERLA: Ongoing
Cobolimab
		COSTAR: Dostarlimab
(GSK4069889):	NSCLC		Combination Trial
Anti-TIM-3 Antagonist			Ongoing

GSK4074386: Immuno-Oncology

Anti-LAG-3 Antagonist

TSR-075:Anti-PD-1/	Immuno-Oncology
LAG-3 Bispecific

CITRINO: Dostarlimab

Combination Trial Ongoing

IND-Enabling

Studies Ongoing

CC-90006:Anti-PD-1	Psoriasis			Ongoing
Agonist
Undisclosed	Inflammation		Ongoing

All programs generated internally using AnaptysBio's

proprietary antibody platform technology

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