Apogee Therapeutics Highlights Progress and Best-in-Class Potential of Novel Biologic Programs for I&I Diseases at 2024 Inaugural R&D Day Positive interim Phase 1 data indicate APG808 was well-tolerated with half-life of

Apogee Therapeutics Highlights Progress and

Best-in-Class Potential of Novel Biologic Programs for I&I Diseases at 2024 Inaugural R&D Day

Positive interim Phase 1 data indicate APG808

was well-tolerated with half-life of approximately 55 days, supporting potential for 2- to 3- month dosing and demonstrating deep and

sustained inhibition of biomarkers

Data up to 12 months reinforce APG777's

best-in-class potential, including 77-day half-life, and provide a potential path to annual dosing

16-week topline data from APG777 Phase 2 Part A

trial in AD accelerated to mid-2025 based on strong enrollment

Preclinical and coformulation proof-of-concept

achieved for APG777 + APG990 combination Phase 1b head-to-head trial against DUPIXENT expected to initiate in 2025 with data in 2H 2026

Preclinical proof-of-concept achieved for APG777

+ APG333 combination in asthma and COPD, clinical trial planning underway

Webcast to be held today at 10:00 a.m. ET

SAN FRANCISCO and WALTHAM, Mass., December 2,

2024 -- Apogee Therapeutics, Inc., (Nasdaq: APGE), a clinical-stage biotechnology company advancing novel biologics with potential

for differentiated efficacy and dosing in the largest inflammatory and immunology (I&I) markets, including for the treatment of atopic

dermatitis (AD), asthma, chronic obstructive pulmonary disease (COPD), eosinophilic esophagitis (EoE) and other I&I indications, will

highlight updates from across its pipeline during today's Virtual R&D Day, being held at 10:00 a.m. ET. Updates include

positive interim results from the APG808 Phase 1 trial, data up to 12 months from the APG777 Phase 1 trial, details around the Company's

strategy for combinations in AD, asthma and COPD to deliver better efficacy and dosing regimens, and the expected significant commercial

potential of its programs. Key opinion leaders, Emma Guttman-Yassky, M.D., Ph.D. and David Singh, M.D., FERS, FBPhS, will also discuss

the current landscape and need for new treatment opportunities for patients living with I&I conditions.

"APG777 is poised to disrupt the atopic dermatitis

market, with our most recent data suggesting potential dosing as infrequently as once per year -- a revolutionary advancement that has

garnered positive feedback from patients, physicians and payers alike," said Michael Henderson, M.D., Chief Executive Officer of

Apogee. "We plan on transforming the standard of care in I&I through

three waves of innovation: progressing APG777's monotherapy program with potential for higher efficacy and transformational dosing

in AD, currently in a Phase 2 Part A 16-week trial, with its proof of concept (PoC) readout that has been accelerated to mid-2025

based on strong enrollment; demonstrating APG777's pipeline-in-a-product

monotherapy potential by expanding into EoE as well as asthma; and advancing the first AD combination PoC trial next year with respiratory

combo planning underway. Beyond its differentiation as a monotherapy, APG777 combined with APG990 as well as with APG333 presents

the opportunity for enhanced efficacy and best-in-class dosing for patients."

"We're pleased to report positive

safety, PK and PD data from the Phase 1 healthy volunteer trial of APG808 at today's R&D Day," said Carl Dambkowski, M.D.,

Chief Medical Officer of Apogee. "Our interim findings demonstrated an approximately 55-day half-life for APG808, a five-fold increase

versus DUPIXENT, suggesting a potential dosing regimen of every 2- to 3-months, compared to every 1-2 weeks for DUPIXENT. We believe the

results support Apogee's ability to engineer optimized antibodies and target known biologic drivers to improve the lives of patients

with I&I conditions. We look forward to further evaluating APG808 in the Phase 1b trial in asthma as well as delivering data on additional

pipeline candidates next year."

APG808 interim Phase 1 healthy volunteer trial

The APG808 Phase 1 trial enrolled 32 healthy adult

participants into four single-ascending dose (SAD) cohorts. Today, Apogee shared interim data from all four SAD cohorts with at least

Accelerating a leading franchise in AD

Apogee is advancing multiple opportunities for

best-in-class monotherapy and first-in-class combination approaches for the treatment of AD that could provide transformational dosing

and efficacy compared to current approved and investigational biologics.

APG777 is a novel, subcutaneous (SQ) extended

half-life monoclonal antibody (mAb) targeting IL-13 with the potential for best-in-class efficacy and dosing compared to currently approved

biologics. APG777 is being evaluated in an ongoing Phase 1 trial, which initiated in August 2023, and a global Phase 2 trial in AD,

which initiated in May 2024.

Raising the bar in AD and beyond via broader

plans to take a first-in-class combination approach to AD by targeting Types 1-3 inflammation potentially offering JAK-like inhibition

without their associated safety concerns. This approach offers the potential for improved clinical responses over monotherapies

and best-in-class dosing.

APG990 is a novel, SQ half-life extended mAb targeting

OX40L, initially being developed for AD. OX40L is located further upstream in the inflammatory pathway than IL-13 and targeting it could

have broader impact on the inflammatory cascade by inhibiting Type 1, Type 2 and Type 3 pathways. Apogee is evaluating APG990 in a Phase

1 healthy volunteer trial to establish safety, tolerability and PK profile, which would enable combination with APG777.

Breaking through the efficacy ceiling in asthma

Apogee plans to take a combination approach to

the treatment of asthma and COPD, leveraging mechanisms that address both central and local drivers of respiratory diseases, potentially

enabling enhanced efficacy and extended dosing regimens.

APG333 is a novel, SQ extended half-life mAb targeting

TSLP, a key driver of Type 2 and Type 3 inflammation in eosinophilic and non-eosinophilic conditions. A Phase 1 trial in healthy volunteers

is planned to commence by the end of 2024, with data expected in the second half of 2025.

Apogee Therapeutic's Virtual R&D Day

will begin at 10:00 a.m. ET. The live webcast can be accessed via this link or News & Events page in

the Investors section of the Apogee Therapeutics website. A replay of the webcast will be archived on the website following the event.

It is recommended that participants register at least 15 minutes in advance of the event.

Apogee Therapeutics is a clinical-stage biotechnology

company advancing novel biologics with potential for differentiated efficacy and dosing in the largest I&I markets, including for

the treatment of AD, asthma, COPD, EoE and other I&I indications. Apogee's antibody programs are designed to overcome limitations

of existing therapies by targeting well-established mechanisms of action and incorporating advanced antibody engineering to optimize

half-life and other properties. APG777, the company's most advanced program, is being initially developed for the treatment of

AD, which is the largest and one of the least penetrated I&I markets. With four validated targets in its portfolio, Apogee is seeking

to achieve best-in-class efficacy and dosing through monotherapies and combinations of its novel antibodies. Based on a broad pipeline

and depth of expertise, the company believes it can deliver value and meaningful benefit to patients underserved by today's standard

of care. For more information, please visit https://apogeetherapeutics.com.

Forward Looking Statements

Certain statements in this press release may

constitute "forward-looking statements" within the meaning of the federal securities laws, including, but not limited to,

statements regarding: Apogee's plans for its current and future product candidates and programs, particularly APG777, APG990 and

APG333; its plans for current and future clinical trials; expected timing for release of data from Apogee's APG808 Phase 1b trial,

Part A of the APG777 Phase 2 trial and APG333 Phase 1 trial; the potential clinical benefit, dosing schedule and half-life of APG777

and APG808; plans for and potential benefit of Apogee's other product candidates, and any other potential programs, including combination

therapies. Words such as "may," "might," "will," "objective," "intend," "should,"

"could," "can," "would," "expect," "believe," "design," "estimate,"

"predict," "potential," "develop," "plan" or the negative of these terms, and similar

expressions, or statements regarding intent, belief, or current expectations, are forward-looking statements. While Apogee believes these

forward-looking statements are reasonable, undue reliance should not be placed on any such forward-looking statements, which are based

on information available to the company on the date of this release. These forward-looking statements are based upon current estimates

and assumptions and are subject to various risks and uncertainties (including, without limitation, those set forth in Apogee's

filings with the U.S. Securities and Exchange Commission (the SEC)), many of which are beyond the company's control and subject

to change. Actual results could be materially different. Risks and uncertainties include: global macroeconomic conditions and related

volatility; expectations regarding the initiation, progress, and expected results of Apogee's preclinical studies, clinical trials

and research and development programs; expectations regarding the timing, completion and outcome of Apogee's clinical trials; the

unpredictable relationship between preclinical study results and clinical study results; the timing or likelihood of regulatory filings

and approvals; liquidity and capital resources; and other risks and uncertainties identified in Apogee's Annual Report on Form 10-K

for the year ended December 31, 2023, filed with the SEC on March 5, 2024, Quarterly Report on 10-Q for the quarterly period