CStone Pharmaceuticals — Share Issue/Capital Change 2025

Apr 10, 2025

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.

Neither this announcement nor any copy thereof may be released into or distributed directly or indirectly in the United States or any other jurisdiction where such release or distribution might be unlawful.

This announcement is for information purpose only and does not constitute an invitation or offer to acquire, purchase or subscribe for any securities of the Company.

This announcement and the information herein do not constitute or form a part of any offer or solicitation to purchase, subscribe or sell securities in the United States. The securities referred to herein have not been and will not be registered under the United States Securities Act of 1933, as amended (the "Securities Act"), or the securities laws of any state of the United States or other jurisdiction. The securities referred to herein are being offered and sold outside the United States in reliance on Regulation S under the Securities Act and may not be offered or sold within the United States absent registration or an applicable exemption from registration under the Securities Act. No public offering of the securities referred to herein will be made in the United States or in any other jurisdiction where such an offering is restricted or prohibited. No money, securities or other consideration is being solicited by this announcement or the information contained herein and, if sent in response to this announcement or the information contained herein, will not be accepted.

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基石药业

CSTONE PHARMACEUTICALS

CStone Pharmaceuticals

基石藥業

(Incorporated in the Cayman Islands with limited liability)

(Stock Code: 2616)

COMPLETION OF PLACING OF NEW SHARES UNDER GENERAL MANDATE

Sole Overall Coordinator, Sole Placing Agent and Sole Bookrunner

Morgan Stanley

The Board is pleased to announce that all conditions of the Placing have been fulfilled and the completion of the Placing took place on April 10, 2025. Pursuant to the terms and conditions of the Placing Agreement, 80,000,000 Placing Shares have been successfully placed by the Placing Agent to not less than six Placees at the Placing Price of HK$2.933 per Placing Share.

Reference is made to the announcement of CStone Pharmaceuticals (the "Company") dated April 2, 2025 in respect of the proposed placing of new Shares under general mandate (the "Announcement"). Unless otherwise stated, the terms used in this announcement shall have the same meaning as defined in the Announcement.

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COMPLETION OF THE PLACING

The Board is pleased to announce that all conditions to the Placing Agreement have been fulfilled and completion of the Placing took place on April 10, 2025. An aggregate of 80,000,000 Placing Shares have been placed by the Placing Agent to not less than six Places at the Placing Price of HK$2.933 per Placing Share pursuant to the terms and conditions of the Placing Agreement, representing approximately 5.86% of the issued share capital of the Company as enlarged by the allotment and issue of the Placing Shares immediately upon completion of the Placing.

To the best of the Directors' knowledge, information and belief, having made all reasonable enquiries, the Places and their respective ultimate beneficial owners are professional, institutional, or other investors who are Independent Third Parties.

The Company received net proceeds from the Placing, after deducting the placing commission and other related expenses and professional fees, of approximately HK$232.29 million. The Company intends to use the net proceeds for the purposes as disclosed in the paragraph headed "Reasons for the Placing and Use of Proceeds" in the Announcement.

SHAREHOLDING STRUCTURE OF THE COMPANY UPON COMPLETION OF THE PLACING

The shareholding structure of the Company immediately before and upon completion of the Placing are set out as follows:

	Immediately before completion of the Placing		Immediately upon completion of the Placing
		Approximate percentage of the issued share capital of the Company		Approximate percentage of the issued share capital of the Company
Name of Shareholders	No. of Shares	—	No. of Shares	—
The Places	—	—	80,000,000	5.86%
Other Shareholders	1,284,380,568	100.00%	1,284,380,568	94.14%
Total	1,284,380,568	100%	1,364,380,568	100%

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Cautionary statement required by Rule 18A.05 of the Listing Rules: There is no assurance that the Company will be able to develop, market, and/or commercialize any of the products in its pipeline successfully, including those specified in the paragraph headed "Reasons for the Placing and Use of Proceeds" in the Announcement. Shareholders and potential investors should exercise due care when dealing in the securities of the Company.

By Order of the Board
CStone Pharmaceuticals
Dr. Wei Li
Chairman

Suzhou, the People's Republic of China, April 10, 2025

As at the date of this announcement, the board of directors of the Company comprises Dr. Wei Li as Chairman and non-executive director, Dr. Jianxin Yang as executive director, Mr. Kenneth Walton Hitchner III, Mr. Xianghong Lin and Mr. Edward Hu as non-executive directors, and Dr. Paul Herbert Chew, Mr. Ting Yuk Anthony Wu, Mr. Hongbin Sun and Ms. Yip Betty Ho as independent non-executive directors.

The Directors jointly and severally accept full responsibility for the accuracy of information contained in this announcement and confirm, having made all reasonable inquiries, that to the best of their acknowledge, opinions expressed in this announcement have been arrived at after due and careful consideration and there are no other facts not contained in this announcement, the omission of which would make any statement in this announcement misleading.

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