VOLUNTARY ANNOUNCEMENT INTENTION TO CONDUCT ON-MARKET SHARE REPURCHASE

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.JACOBIO PHARMACEUTICALS GROUP CO. LTD.加科思药业集团有限公司 (Incorporated in the Cayman Islands with limited liability) (Stock Code: 1167) VOLUNTARY ANNOUNCEMENT INTENTION TO CONDUCT ON-MARKET SHARE REPURCHASE This announcement is made by JACOBIO PHARMACEUTICALS GROUP CO. LTD. (the “Company” together with its subsidiaries the “Group”) on a voluntary basis to inform the shareholders of the Company (the “Shareholders”) and potential investors about the latest developments of the Group.The board (the “Board”) of directors (the “Director(s)”) of the Company wishes to announcethat it has an intention to exercise its powers under the general mandate (the “Share RepurchaseMandate”) given to the Board pursuant to the resolutions of the Shareholders passed at the annual general meeting of the Company (the “AGM”) held on June 7 2024 to repurchase up to 79175508 shares of the Company (the “Shares”) being 10% of the total number of the issued Shares as at the date of the AGM (the “Proposed Share Repurchase”) with such mandate to expire upon whichever is the earliest of: (a) the conclusion of the next annual general meeting of the Company; or (b) the expiration of the period within which the next annual general meeting of the Company is required by the articles of association of the Company or any applicable law of the Cayman Islands to be held; or (c) the date on which the authority set out in the ordinary resolution approving the Share Repurchase Mandate is revoked or varied by an ordinary resolution of the Shareholders in general meeting.The Board has decided to utilize the Share Repurchase Mandate to repurchase Shares in the open market from time to time in accordance with market conditions and use up to a maximum of HK$100 million for the Proposed Share Repurchase. The Company intends to fund the Proposed Share Repurchase from its own financial resources and not from the proceeds of the listing of the Shares on the Main Board of The Stock Exchange of Hong Kong Limited. No repurchases would be made in circumstances that would have a material adverse impact on the working capital position of the Company. 1The Company will conduct the Proposed Share Repurchase in compliance with the memorandum and articles of association of the Company the Rules Governing the Listing of Securities on The Stock Exchange of Hong Kong Limited (the “Listing Rules”) the Codes on Takeovers and Mergers and Share Buy-backs the Companies Act of the Cayman Islands and all applicable laws and regulations to which the Company is subject to the actual repurchase price of each Share shall be no more than 5% higher than the average closing market price for the Shares over the five trading days immediately preceding each repurchase. The Company may make further repurchases of Shares according to market conditions until the expiry of the Share Repurchase Mandate but in any case subject to the availability of the Share Repurchase Mandate. The Proposed Share Repurchase shall not result in the number of the Shares held by the public falling below the relevant minimum percentage prescribed by the Listing Rules. Any Shares repurchased pursuant to the Proposed Share Repurchase may be canceled or held in treasury.The Company’s business development and operations are currently normal and its current financial position is healthy. The Board is of the view that the current trading price of the Shares does not reflect their intrinsic value and the Proposed Share Repurchase will enhance the value of the Shares thereby increasing the returns to the Shareholders. In addition the Board believes that the Proposed Share Repurchase reflects the Company’s confidence in its long-term business prospects and the Company’s growth potential which will ultimately benefit the Company and is in the best interests of the Company and the Shareholders as a whole.At the time of publication of this announcement the Company has not repurchased any Shares under the Share Repurchase Mandate. Shareholders and potential investors should note that repurchases of Shares under the Share Repurchase Mandate will be subject to market conditions and at the absolute discretion of the Board. There is no assurance of the timing quantity or price of any repurchases or whether or not the Company will make any repurchases. Accordingly Shareholders and potential investors are reminded to exercise caution when dealing in the securities of the Company.By Order of the Board JACOBIO PHARMACEUTICALS GROUP CO. LTD.Yinxiang WANG Chairman Hong Kong June 11 2024 As at the date of this announcement the Board comprises Dr. Yinxiang WANG as Chairman and executive Director Ms. Xiaojie WANG and Ms. Yunyan HU as executive Directors Ms. Yanmin TANG and Dr. Te-li CHEN as non-executive Directors and Dr. Ruilin SONG Dr. Bai LU and Dr.Ge WU as independent non-executive Directors. 2