JOINT ANNOUNCEMENTEXTENSION OF TIME FOR DESPATCH OF THECOMPOSITE DOCUMENTANDMONTHLY UPDATEIN RELATION TO THE PROPOSED PRE-CONDITIONAL PRIVATISATION OFYICHANG HEC CHANGJIANG PHARMACEUTICAL CO., LTD. BYSUNSHINE LAKE PHARMA CO., LTD.BY WAY OF MERGER BY ABSORPTION OFYICHANG HEC CHANGJIANG PHARMACEUTICAL CO., LTD.

Hong Kong Exchanges and Clearing Limited and The Stock Exchange of Hong Kong Limited take no responsibility for the contents of this joint 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 joint announcement.This joint announcement appears for information purposes only and is not intended to and does not constitute or form part of any offer to purchase or subscribe for or an invitation to purchase or subscribe for securities of the Offeror or the Company or the solicitation of any vote or approval in any jurisdiction nor shall there be any sale issuance or transfer of securities of the Offeror or the Company in any jurisdiction in contravention of applicable law or regulation.This joint announcement is not for release publication or distribution in whole or in part in into or from any jurisdiction where to do so would constitute a violation of the applicable laws or regulations of such jurisdiction.广东东阳光药业股份有限公司宜昌东阳光长江药业股份有限公司 SUNSHINE LAKE PHARMA YICHANG HEC CHANGJIANG CO. LTD. PHARMACEUTICAL CO. LTD.(a company incorporated in the People’s Republic of (a joint stock limited company incorporated in the China with limited liability) People’s Republic of China with limited liability) (Stock Code: 1558) JOINT ANNOUNCEMENT EXTENSION OF TIME FOR DESPATCH OF THE COMPOSITE DOCUMENT AND MONTHLY UPDATE IN RELATION TO THE PROPOSED PRE-CONDITIONAL PRIVATISATION OF YICHANG HEC CHANGJIANG PHARMACEUTICAL CO. LTD. BY SUNSHINE LAKE PHARMA CO. LTD.BY WAY OF MERGER BY ABSORPTION OF YICHANG HEC CHANGJIANG PHARMACEUTICAL CO. LTD.Financial Adviser to the Offeror Financial Adviser to the Company – 1 –Reference is made to the announcement jointly published by Sunshine Lake Pharma Co.Ltd. (the ‘‘Offeror’’) and YiChang HEC ChangJiang Pharmaceutical Co. Ltd. (the ‘‘Company’’) on 10 May 2024 (the ‘‘Joint Announcement’’) in relation to the Merger.Unless the context requires otherwise capitalised terms used herein shall have the same meanings as those defined in the Joint Announcement.PROGRESS UPDATE ON THE MERGER As stated in the Joint Announcement the Merger Agreement is subject to the fulfilment of the Pre-Conditions being (1) the approval filing or registration (if applicable) with or by (a) NDRC (if applicable); (b) MoC (if applicable) and (c) SAFE (if applicable) and such other applicable governmental approvals in respect of the Merger having been obtained (2) the approval or filing by or with the Listing Committee of the Stock Exchange the Department of International Cooperation of the CSRC and such other competent authorities which are necessary for the listing (by way of introduction) of and permission to deal in the Offeror H Shares on the Stock Exchange pursuant to the Listing and (3) approval by the shareholders meeting of the Offeror of the Merger in accordance with the PRC Laws and the articles of association of the Offeror.Since the publication of the Joint Announcement steps have been taken to fulfil the Pre- Conditions. As at the date of this joint announcement none of the Pre-Conditions has been fulfilled yet.DELAY IN DESPATCH OF THE COMPOSITE DOCUMENT Pursuant to Rule 8.2 of the Takeovers Code unless the Executive’s consent is obtained the Offeror and the Company should normally despatch the Composite Document within 35 days of the date of the Joint Announcement which in this case would be on or before 14 June 2024. As more time is required for the fulfilment of Pre-Conditions an application was made to the Executive pursuant to Note 2 to Rule 8.2 of the Takeovers Code and the Executive has granted consent to extend the latest date for the despatch of the Composite Document to (i) within 7 days after the fulfillment of the Pre-Conditions or (ii) 7 July 2025 whichever is earlier. Further announcement(s) will be made as and when appropriate in compliance with the Takeovers Code and upon the fulfilment of the Pre-Conditions and the despatch of the Composite Document.– 2 –WARNING: The Pre-Conditions and the Conditions to effectiveness must be fulfilled before the Merger Agreement becomes effective. The Merger Agreement becoming effective is therefore a possibility only. Further Shareholders investors and potential investors in the securities of the Company should be aware that the implementation of the Merger is subject to the Conditions to implementation set out in the Joint Announcement being satisfied or waived as applicable. Neither the Offeror nor the Company provides any assurance that any or all Conditions or Pre-Conditions can be fulfilled and thus the Merger Agreement may or may not become effective or if effective may or may not be implemented or completed. Shareholders investors and potential investors in the securities of the Company should therefore exercise caution when dealing in the securities of the Company. Persons who are in doubt as to the action to take and the implications arising from the Merger should consult their stockbroker bank manager solicitor or other professional advisers (including tax adviser regarding the tax consequences of the cancellation of the Shares and the implementation of the Merger).By order of the board of By order of the board of Sunshine Lake Pharma Co. Ltd. YiChang HEC ChangJiang Pharmaceutical ZHANG Yingjun Co. Ltd.Chairman TANG Xinfa Chairman Hubei the PRC 7 June 2024 As at the date of this joint announcement the Offeror’s directors are Dr. ZHANG Yingjun Dr. LI Wenjia Mr. Zhang Yushuai Mr. TANG Xinfa Mr. ZHU Yingwei Ms. DONG Xiaowei Ms. WANG Lei Dr. LI Xintian Dr. MA Dawei Dr. YIN Hang Hubert and Dr. LIN Aimei. The directors of the Offeror jointly and severally accept full responsibility for the accuracy of the information contained in this joint announcement (other than in relation to the Company or the Directors in their capacity as such) and confirm having made all reasonable enquiries that to the best of their knowledge opinions expressed in this joint announcement (other than those expressed by the Company or the Directors in their capacity as such) have been arrived at after due and careful consideration and there are no other facts not contained in this joint announcement the omission of which would make any of the statements in this joint announcement misleading.As at the date of this joint announcement the Board consists of Mr. JIANG Juncai Mr.WANG Danjin Mr. LI Shuang and Mr. CHEN Hao as executive Directors; Mr. TANG Xinfa as non-executive Director; and Mr. TANG Jianxin Ms. XIANG Ling and Mr. LI Xuechen as independent non-executive Directors. The Directors jointly and severally accept full responsibility for the accuracy of the information contained in this joint announcement (other than in relation to the Offeror or its directors in their capacity as such) and confirm having made all reasonable enquiries that to the best of their knowledge opinions expressed in this joint announcement (other than those expressed by the Offeror or its directors in their capacity as such) have been arrived at after due and careful consideration and there are no other facts not contained in this joint announcement the omission of which would make any of the statements in this joint announcement misleading.–3–