Adagene Presents Results at ESMO Congress that Show Best-in-Class Therapeutic Potential for Anti-CTLA-4 SAFEbody ADG126 (Muzastotug) in Combination with KEYTRUDA (Pembrolizumab) in Advanced/Metastatic Microsatellite-stab

Presents Results at ESMO Congress that Show Best-in-Class Therapeutic Potential for Anti-CTLA-4 SAFEbody ADG126 (Muzastotug)

in Combination with KEYTRUDA (Pembrolizumab) in Advanced/Metastatic Microsatellite-stable

(MSS) Colorectal Cancer (CRC)

partial responses (PRs) doubled to four since ASCO GI in MSS CRC patients without liver and peritoneal metastases for overall

response rate (ORR) of 24% (4/17) with ADG126 10 mg/kg every three weeks (Q3W) in combination with pembrolizumab -

Median progression-free survival of 8.5 months observed in patients

without liver and peritoneal metastases at the ADG126 10 mg/kg Q3W dose -

- At the 10 mg/kg dose level, 12-month overall

survival (OS) rates were 74% for patients without liver metastases, and 82% for those without liver and peritoneal metastases -

profile maintained, with only 16% Grade 3 TRAEs in patients treated with ADG126 10 mg/kg Q3W in combination with pembrolizumab

shows potential with standard of care to address broader patient populations, including MSS CRC patients with liver metastases -

SAN DIEGO and SUZHOU, China, September 16, 2024-- Adagene Inc.

("Adagene") (Nasdaq: ADAG), a company transforming the discovery and development of novel antibody-based therapies, today

announced new ADG126 clinical data presented at the ESMO Congress, taking place in Barcelona, Spain, September 13-17.

poster, titled Increased Therapeutic Index of Muzastotug (ADG126), a Masked Anti-CTLA-4 Antibody, in Combination with Pembrolizumab

(Pembro) Enables Significant Clinical Benefits and Supports Further Clinical Development in Patients with Metastatic MSS CRC, reports

data from an ongoing phase 1b/2 trial of Adagene's masked anti-CTLA-4 SAFEbody in combination with Merck & Co., Inc.,

Rahway, NJ, USA's anti-PD-1 therapy KEYTRUDA (pembrolizumab) (ADG126-P001; NCT05405595).

"I am delighted that the ESMO data show

a promising overall response rate, progression-free survival (PFS) and early survival benefit from treatment with the immunotherapy (IO)

doublet of ADG126 in combination with pembrolizumab for patients with advanced/metastatic MSS CRC, the largest segment of colorectal cancer

with few treatment options," said Daneng Li, MD, Associate Professor in the Department of Medical Oncology & Therapeutics

Research at the City of Hope Comprehensive Cancer Center, and a study investigator. "With a much higher dosing level

than available anti-CTLA-4 therapies, these data reinforce the encouraging safety and efficacy profile for ADG126 administered repeatedly

Dr. Li continued, "Given the best-in-class

potential for ADG126, this combination with pembrolizumab could address even broader patient populations, such as those with liver

metastases, particularly if combined with standard of care to control early disease progression. Further, the safety profile of this immunotherapy

doublet enables repeat cycles to achieve and sustain sufficient drug exposure that maximizes potential for a long-term survival benefit."

ADG126 is a masked anti-CTLA-4 SAFEbody targeting a unique epitope

of CTLA-4 on regulatory T cells (Tregs) in tumor tissue which shows potential best-in-class safety and efficacy profiles in combination

with pembrolizumab. The unique epitope of ADG126 alone has shown enhanced antibody-dependent cell mediated cytotoxicity without Fc engineering,

which is associated with significantly increased toxicity. Further, it has shown minimal immunogenicity and anti-drug antibodies, with

no impact on its pharmacokinetic (PK) profile.

highlights from the poster (July 30, 2024 data cutoff) include:

Commenting on these promising results, Peter Luo, Adagene's CEO

and President of R&D said, "We are thrilled that today's update continues to reinforce the clinical benefits of the best-in-class

therapeutic potential for ADG126 at the 10 mg/kg dose level in combination with pembrolizumab in MSS CRC. Armed with these results and

the anticipated findings from our ongoing 20 mg/kg loading dose regimen, we are moving ahead with plans to evaluate ADG126 in MSS CRC

at 10- to 20-fold higher doses than ipilimumab in a randomized, registration-oriented clinical program. With safety comparable to historical

data for pembrolizumab monotherapy, these data provide a solid foundation for the potential of an IO doublet targeting CTLA-4 and PD-1

to move into earlier lines of therapy and broader patient populations, particularly when combined with standard of care aiming for a transformational

improvement in patient outcomes."

is a registered trademark of Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ,

SAFEbody is a registered

trademark in the United States, China, Australia, Japan, Singapore, and the European Union.

Lancet. 2013;381: 303-312; FDA label, 12/10/2020. Mayer et al. N Eng J Med. 2015;372: 1909-1919. Marcus

et al. Clin Cancer Res; 23(12) June 15, 2017;2924-2927. Josep Tabernero et al. 2023 ASCO Gastrointestinal. Gerald W. Prager

et al. N Engl J Med 2023 May 04;388(18). Shukui Qin et al. 2019 CSCO. Jin Li et al. JAMA. 2018;319(24): 2486-2496. Andrea J. Bullock et al. 2023 ESMO-GI.

Anthony B et al. 2023 ASCO-GI. Elena et al. 2021 ASCO. E. Garralda et al. 2022 ESMO.

Inc. (Nasdaq: ADAG) is a platform-driven, clinical-stage biotechnology company committed to transforming the discovery and development

of novel antibody-based cancer immunotherapies. Adagene combines computational biology and artificial intelligence to design

novel antibodies that address globally unmet patient needs. The company has forged strategic collaborations with reputable global partners

that leverage its SAFEbody precision masking technology in multiple approaches at the vanguard of science.

Powered by its proprietary Dynamic

Precision Library (DPL) platform, composed of NEObody , SAFEbody, and POWERbody technologies, Adagene's highly

differentiated pipeline features novel immunotherapy programs. The company's SAFEbody technology is designed to address safety and

tolerability challenges associated with many antibody therapeutics by using precision masking technology to shield the binding domain

of the biologic therapy. Through activation in the tumor microenvironment, this allows for tumor-specific targeting of antibodies in tumor

microenvironment, while minimizing on-target off-tumor toxicity in healthy tissues.

Adagene's lead clinical

program, ADG126 (Muzastotug), is a masked, anti-CTLA-4 SAFEbody that targets a unique epitope of CTLA-4 in regulatory T cells (Tregs)

in the tumor microenvironment. ADG126 is currently in phase 1b/2 clinical studies in combination with anti-PD-1 therapy, particularly

focused on Metastatic Microsatellite-stable (MSS) Colorectal Cancer (CRC). Validated by ongoing clinical research, the SAFEbody platform

can be applied to a wide variety of antibody-based therapeutic modalities, including Fc empowered antibodies, antibody-drug conjugates,

and bi/multispecific T-cell engagers.

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Safe Harbor Statement

This press release contains forward-looking statements, including statements

regarding certain clinical results of ADG126, the potential implications of clinical data for patients, and Adagene's advancement

of, and anticipated preclinical activities, clinical development, regulatory milestones, and commercialization of its product candidates.

Actual results may differ materially from those indicated in the forward-looking statements as a result of various important factors,

including but not limited to Adagene's ability to demonstrate the safety and efficacy of its drug candidates; the clinical results

for its drug candidates, which may not support further development or regulatory approval; the content and timing of decisions made by

the relevant regulatory authorities regarding regulatory approval of Adagene's drug candidates; Adagene's ability to achieve

commercial success for its drug candidates, if approved; Adagene's ability to obtain and maintain protection of intellectual property

for its technology and drugs; Adagene's reliance on third parties to conduct drug development, manufacturing and other services;

Adagene's limited operating history and Adagene's ability to obtain additional funding for operations and to complete the

development and commercialization of its drug candidates; Adagene's ability to enter into additional collaboration agreements beyond

its existing strategic partnerships or collaborations, and the impact of the COVID-19 pandemic on Adagene's clinical development,

commercial and other operations, as well as those risks more fully discussed in the "Risk Factors" section in Adagene's

filings with the U.S. Securities and Exchange Commission. All forward-looking statements are based on information currently available

to Adagene, and Adagene undertakes no obligation to publicly update or revise any forward-looking statements, whether as

a result of new information, future events or otherwise, except as may be required by law.

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