Voluntary and Business Update Announcement New Drug Application of Methylthioninium Chloride Enteric-coated Sustained-release Tablets Lumeblue Approved in China

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.CHINA MEDICAL SYSTEM HOLDINGS LIMITED 康哲药业控股有限公司* (Incorporated in the Cayman Islands with limited liability) (Stock Code: 867) Voluntary and Business Update Announcement New Drug Application of Methylthioninium Chloride Enteric-coated Sustained-release Tablets Lumeblue Approved in China China Medical System Holdings Limited (the “Company” together with its subsidiaries the “Group”) is pleased to announce that on 11 June 2024 the New Drug Application (NDA) of the Group’s innovative drug methylthioninium chloride enteric-coated sustained-release tablets Lumeblue (“Lumeblue” or the “Product”) has been approved by the National Medical Products Administration of China (NMPA). The drug registration certificate was obtained on 18 June 2024. The Product is indicated to enhancing visualisation of colorectal lesions in adult patients undergoing screening or surveillance colonoscopy.Lumeblue is an oral diagnostic drug that uses patented multi-matrix (MMX) technology to deliver active substances directly to the colon and release them locally in a controlled manner.As an enhancer dye the Product increases the contrast between colorectal lesions and healthy mucosa. The results of the Phase III clinical trial in China show that the Product can significantly improve the detection rate of non-polypoid colorectal lesions (the primary endpoint of the study) leading to an improved detection rate of dangerous lesions such as non-polypoid adenomas (the secondary endpoint). In addition the Product can be taken during the bowel preparation step ensuring that colorectal staining is completed by the time colonoscopy is conducted. This not only enhances the detection rate of colorectal lesions but also potentially simplifies the colonoscopy procedure making the examination more efficient and improving the screening benefits. According to the diagnosis and treatment data of the Digestive Endoscopy Branch of the Chinese Medical Association approximately a total of 28 million gastroenteroscopies were completed nationwide in 2012 including 5.83 million *For identification purpose onlycolonoscopies. In 2019 approximately 38.73 million gastroenteroscopies were completed nationwide an increase of 34.62% compared with 2012. The "Chinese Consensus of Early Colorectal Cancer Screening" recommends that people aged 50 to 75 years old should be screened for colorectal cancer regardless of whether they have alarm symptoms. There are approximately 400 million people aged 50 to 75 in China in 2020. With the popularity of early screening for colorectal cancer in China it is expected to witness a considerable growth of the number of colonoscopies in China in the future.Lumeblue has been approved by the European Medicines Agency (EMA) to be commercialized in the European Union under the trade name Lumeblue in August 2020.The Group obtained an exclusive license for the Product from Cosmo Technologies Ltd. on 3 December 2020. The Group will promote the commercialization of the Product in an orderly manner to benefit patients with colorectal disease at an early date.This announcement is made on a voluntary basis by the Company and aims to inform potential investors and shareholders of the Company of the latest business developments of the Group. Shareholders and investors are advised to exercise caution in dealing in the shares and other securities of the Company.By order of the Board China Medical System Holdings Limited Lam Kong Chairman Hong Kong 18 June 2024 As at the date of the announcement the directors of the Company comprise (i) Mr. Lam Kong Mr. Chen Hongbing and Ms. Chen Yanling as executive directors; and (ii) Mr. Leung Chong Shun Ms. Luo Laura Ying and Mr. Fung Ching Simon as independent non-executive directors.