ASCLETIS-B - VOLUNTARY ANNOUNCEMENT -

ASCLETIS ANNOUNCES FIXED-DOSE COMBINATION OF ASC30, ONCE-DAILY ORAL SMALL MOLECULE GLP-1R AGONIST, AND ASC39, ONCE-DAILY ORAL SMALL MOLECULE AMYLIN-SELECTIVE AMYLIN RECEPTOR AGONIST, FOR CLINICAL DEVELOPMENT

Ascletis Pharma Inc.

歌禮製藥有限公司

(incorporated in the Cayman Islands with limited liability)

(Stock Code: 1672)

VOLUNTARY ANNOUNCEMENT

ASCLETIS ANNOUNCES FIXED-DOSE COMBINATION OF ASC30, ONCE-

DAILY ORAL SMALL MOLECULE GLP-1R AGONIST, AND ASC39, ONCE-DAILY ORAL SMALL MOLECULE AMYLIN-SELECTIVE AMYLIN

RECEPTOR AGONIST, FOR CLINICAL DEVELOPMENT

– Fixed-dose combination of ASC30 and ASC39 (ASC30_39 FDC) tablets, dosed orally in dogs, demonstrated comparable pharmacokinetics to those observed in their respective monotherapies in a head-to-head study. The fixed dose combination had excellent oral bioavailability, drug exposure and a half-life of up to 12 hours. These data support ASC30_39

FDC tablets as a potential novel one-pill-once-daily therapy for obesity.

– ASC30_39 FDC demonstrated excellent compatibility between ASC30 and ASC39 when

combined together, with room temperature stability and a small pill size.

– ASC30 is a Phase III-ready oral small molecule GLP-1R agonist that had a favorable gastrointestinal (GI) profile with half the rate of vomiting vs. orforglipron, when both drugs

are dosed with weekly titration.

– ASC39, an oral small molecule amylin-selective amylin receptor agonist, demonstrated

eloralintide-like amylin selectivity and efficacy in preclinical models.

– Submission of an Investigational New Drug Application (IND) to the U.S. Food and Drug Administration (FDA) for ASC30_39 FDC oral tablets is expected in the third quarter of

This announcement is made by Ascletis Pharma Inc. (the "Company" or "Ascletis", together with its subsidiaries, the "Group") on a voluntary basis for the purpose of keeping the shareholders of the Company and potential investors abreast of the latest business development of the Group.

The board (the "Board") of directors (the "Directors") of the Company announces that it has selected ASC30_39 FDC, a fixed-dose combination (FDC) of ASC30, once-daily oral small molecule GLP-1R agonist and ASC39, once-daily oral small molecule amylin-selective amylin receptor agonist, for clinical development. Ascletis expects to submit an Investigational New Drug Application (IND) to the U.S. Food and Drug Administration (FDA) for ASC30_39 FDC oral tablets for the treatment of obesity in the third quarter of 2026.

ASC30_39 FDC tablets, dosed orally in dogs, demonstrated excellent oral bioavailability, high drug exposure and a long half-life of up to 12 hours. These key parameters of ASC30_39 FDC tablets are consistent with those observed in their respective monotherapies in a head-to-head dog study. Furthermore, ASC30_39 FDC tablets, developed utilizing Ascletis' proprietary formulation technology, demonstrated a good compatibility between ASC30 and ASC39 with room temperature stability and a small pill size. The combination of the excellent pharmacokinetic profile of ASC30_39 FDC, the potential best-in-class efficacy and gastrointestinal (GI) tolerability of ASC30 and the first eloralintide-like small molecule amylin support ASC30_39 FDC tablets as a potential novel one-pill-once-daily therapy for the treatment of obesity.

ASC30 is a Phase III-ready oral small molecule GLP-1R agonist that had a favorable gastrointestinal (GI) profile with half the rate of vomiting vs. orforglipron, when both drugs are dosed with weekly titration in non-head-to-head studies. Reference is made to the announcement of the Company dated December 8, 2025.

As a clinical development candidate, ASC39 is a potent and amylin-selective oral small molecule amylin receptor agonist and demonstrated eloralintide-like amylin selectivity and efficacy in preclinical models.

"Selection of this fixed dose combination, which we believe is the first publicly announced co-formulation of an oral GLP-1 and an oral amylin, is an important step in the development of a new oral, potentially synergistic combination of ASC30 and ASC39 for the treatment of obesity," said Jinzi Jason Wu, Ph.D., Founder, Chairman of the Board and chief executive officer of Ascletis. "We believe this fixed dose combination, which combines the key features of high bioavailability, high drug exposure, a long half-life, and the convenience of a small pill, has the opportunity to improve patient outcomes for the treatment of obesity."

Cautionary Statement required by Rule 18A.05 of the Rules Governing the Listing of

Securities on The Stock Exchange of Hong Kong Limited: We cannot guarantee that we will be able to ultimately develop, manufacture and/or commercialize ASC30_39 FDC, ASC30 and/or ASC39 successfully.

By order of the Board

Ascletis Pharma Inc.歌禮製藥有限公司Jinzi Jason WU

Chairman

Hong Kong

April 7, 2026