AAPG 6-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 6-K

Report of Foreign Private Issuer

Pursuant to Rule 13a-16 or 15d-16

under the Securities Exchange Act of 1934

For the month of April 2026

Commission File Number: 001-42484

ASCENTAGE PHARMA GROUP INTERNATIONAL

(Translation of Registrant’s name into English)

68 Xinqing Road

Suzhou Industrial Park

Suzhou, Jiangsu

China

(Address of principal executive offices)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F ☒ Form 40-F ☐

On April 1, 2026, Ascentage Pharma Group International (“Ascentage Pharma” or the “Company”) issued an announcement entitled, “Change of Principal Place of Business in Hong Kong”. A copy of the announcement is furnished as Exhibit 99.1 to this Report.

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INDEX TO EXHIBITS

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SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

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Exhibit 99.1

Hong Kong Exchanges and Clearing Limited and The Stock Exchange of Hong Kong Limited take no responsibility for the contents of this announcement, make no representation as to its accuracy or completeness and expressly disclaim any liability whatsoever for any loss howsoever arising from or in reliance upon the whole or any part of the contents of this announcement.

ASCENTAGE PHARMA GROUP INTERNATIONAL

亞盛醫藥集團

(Incorporated in the Cayman Islands with limited liability)

(Stock Code: 6855)

CHANGE OF PRINCIPAL PLACE OF BUSINESS IN HONG KONG

The board (the “Board”) of directors (the “Directors”) of Ascentage Pharma Group International (the “Company”) announces that the principal place of business of the Company in Hong Kong has been changed to Unit 906, 9/F., Haleson Building, 1 Jubilee Street, Central, Hong Kong with effect from April 1, 2026.

Suzhou, People’s Republic of China, April 1, 2026

As at the date of this announcement, the Board comprises Dr. Yang Dajun as Chairman and executive Director, Dr. Wang Shaomeng and Dr. Lu Simon DazhongNote1 as non-executive Directors, and Mr. Ye Changqing, Mr. Ren Wei and Dr. David SidranskyNote2 and Ms. Marina S. Bozilenko and Dr. Debra Yu and Marc E. Lippman, MD as independent non-executive Directors.

Notes: