THIS DOCUMENT IS IN DRAFT FORM, INCOMPLETE AND SUBJECT TO CHANGE AND THE INFORMATION MUST BE READ IN CONJUNCTION WITH THE SECTION HEADED “WARNING” ON THE COVER OF THIS DOCUMENT HISTORY AND CORPORATE STRUCTURE OVERVIEW We are an innovative vaccine company with a high-value prophylactic and therapeutic vaccine pipeline driven by in-house developed technology platforms. The history of our Group can be traced back to April 2009, when our Company was founded by Dr. Wang in Beijing as a limited liability company. For details of the background and experience of Dr. Wang, please refer to the section headed “Directors, Supervisors and Senior Management” in this document. On December 20, 2020, the promoters of the Company entered into a promoters’ agreement, pursuant to which, the promoters of the Company agreed to convert the Company into a joint stock limited liability company with a registered capital of RMB25,920,000. The conversion was completed on December 31, 2020. KEY MILESTONES The following table sets forth the key milestones of our business and corporate development: Year Key milestones and achievements October 2016 We completed the pilot test for ADV110. February 2017 We established our principal operating subsidiary, Suzhou Advaccine. March 2017 We completed the Round I Investment (as defined below) and raised approximately RMB20 million. July 2018 We initiated the Phase I clinical trial of ADV110 in Australia. November 2019 We successfully completed the Phase I clinical trial of ADV110. January 2020 We entered into a memorandum of understanding with Inovio relating to the initiation of co-development of pGX9501/INO-4800 against COVID-19. February 2020 We completed the Round II Investment (as defined below) and raised approximately RMB40 million. June 2020 We completed the Round III Investment (as defined below) and raised approximately RMB42 million. July 2020 We obtained the umbrella approval for initiation of Phase I/II clinical trials of pGX9501 from the NMPA. – 136 – THIS DOCUMENT IS IN DRAFT FORM, INCOMPLETE AND SUBJECT TO CHANGE AND THE INFORMATION MUST BE READ IN CONJUNCTION WITH THE SECTION HEADED “WARNING” ON THE COVER OF THIS DOCUMENT HISTORY AND CORPORATE STRUCTURE Year Key milestones and achievements September 2020 We initiated the Phase I clinical trial of pGX9501 and also received the approval for the commencement of Phase II clinical trial of ADV110 in Australia. We acquired Suzhou Si’ao with a manufacturing center of over 18,000 square meters. November 2020 We received an approval letter from the Ethics Committee of Jiangsu Provincial Center for Disease Control and Prevention (江蘇省疾病預防控制中心倫理審查委員會) for the commencement of Phase II clinical trial of pGX9501. We completed the Round IV Investment (as defined below) and raised approximately RMB220 million. December 2020 We commenced the Phase II clinical trial of pGX9501 and successfully completed the enrollment as well as the first dosing of all planned trial subjects. We entered into the collaboration agreement with Inovio relating to joint development, manufacturing and commercialization of pGX9501/INO-4800. Our Company was converted into a joint stock company. Suzhou Advaccine was accredited as a “High- and New- Technology Enterprise”. March 2021 We completed the Round V Investment (as defined below) and raised approximately RMB432 million. MAJOR SHAREHOLDING CHANGES OF OUR COMPANY Early Years Our Company was established in the PRC as a limited liability company on April 8, 2009 with an initial registered capital of RMB500,000. Upon its establishment, our Company was wholly owned by Dr. Wang and his family member(s). With its ongoing development, the Company’s registered capital was increased to RMB10,000,000 by August 2015. In July 2016, as a reward and repayment for the capital support provided by Dr. Ma at our early development stage, 25% equity interest of our Company was transferred to Dr. Ma, upon completion of which, our Company was owned as to 75% by Ms. Yu and 25% by Dr. Ma. Dr. Ma is our Supervisor and the mother of Mr. Lunan ZHANG (張璐楠), one of our Executive Directors. – 137 – THIS DOCUMENT IS IN DRAFT FORM, INCOMPLETE AND SUBJECT TO CHANGE AND THE INFORMATION MUST BE READ IN CONJUNCTION WITH THE SECTION HEADED “WARNING” ON THE COVER OF THIS DOCUMENT HISTORY AND CORPORATE STRUCTURE Since its establishment, our Company has undertaken a series of capital increases to raise funds for our business development and to bring in new shareholders to our Company. The major shareholding changes of our Company are set out below: Round I Investment On December 23, 2016, our Company, Ms. Yu, Dr. Ma and Dr. Wang entered into a capital increase agreement with Shenzhen Dachen Chuanglian Equity Investment Fund Partnership (Limited Partnership) (深圳市達晨創聯股權投資基金合夥企業(有限合夥)) (“Dachen Chuanglian”), Jiaxing Stars Xuanyuan Investment Partnership (Limited Partnership) (嘉興星 空軒轅投資合夥企業(有限合夥)) (“Stars Xuanyuan”), Nanjing Heheng Investment Center (Limited Partnership) (南京和恒投資中心(有限合夥)) (“Heheng Investment”) and Shenzhen Taiji Investment Enterprise (Limited Partnership) (深圳泰極投資企業(有限合夥)) (“Taiji Investment”, together with Dachen Chuanglian, Stars Xuanyuan, Heheng Investment, collectively, the “Round I Investors”), pursuant to which the Round I Investors agreed to subscribe the increased registered capital of our Company of RMB2,500,000 at a total consideration of RMB20,000,000 (the “Round I Investment”). The consideration was determined based on arm’s length negotiation between the parties taking into account the Company’s research and development progress, pipeline candidates, management team, future prospects and strategic needs. The following table sets forth details of the Round I Investment: Date by which the Registered capital consideration was No. Name of investors subscribed Consideration fully settled 1. Dachen Chuanglian RMB1,250,000 RMB10,000,000 December 30, 2016 2. Stars Xuanyuan RMB625,000 RMB5,000,000 April 27, 2017 3. Heheng Investment RMB375,000 RMB3,000,000 December 29, 2016 4. Taiji Investment RMB250,000 RMB2,000,000 January 3, 2017 Upon completion of the Round I Investment in April 2017, the registered capital of our Company was increased to RMB12,500,000 and our Company was owned as to 60% by Ms. Yu, 20% by Dr. Ma, 10% by Dachen Chuanglian, 5% by Stars Xuanyuan, 3% by Heheng Investment and 2% by Taiji Investment, respectively. For further details, please see “—Pre-[REDACTED] Investments.” Establishment of Domestic Shareholding Platform In order to reward and incentivize our talents and employees for their contribution or potential contribution to our Group, Advaccine Investment was established as a limited partnership in the PRC on October 17, 2017 as our domestic shareholding platform. – 138 – THIS DOCUMENT IS IN DRAFT FORM, INCOMPLETE AND SUBJECT TO CHANGE AND THE INFORMATION MUST BE READ IN CONJUNCTION WITH THE SECTION HEADED “WARNING” ON THE COVER OF THIS DOCUMENT HISTORY AND CORPORATE STRUCTURE On October 23, 2017, Advaccine Investment entered into transfer agreements with Ms. Yu and Dr. Ma, respectively, pursuant to which Ms. Yu and Dr. Ma agreed to transfer to Advaccine Investment the share capital of RMB1,125,000 and RMB375,000, representing 9% and 3% of the then registered capital of the Company, at a consideration of RMB1,125,000 and RMB375,000, respectively. Upon completion of the aforesaid equity transfers in January 2018, our Company was owned as to 51.00% by Ms. Yu, 17.00% by Dr. Ma, 12.00% by Advaccine Investment, 10.00% by Dachen Chuanglian, 5.00% by Stars Xuanyuan, 3.00% by Heheng Investment and 2.00% by Taiji Investment, respectively. As of the Latest Practicable Date, Advaccine Investment was owned by Ms. Yu, Dr. Ma and Ms. Zhou LU (陸洲), our Supervisor, as to 68.60%, 22.87% and 8.54%, respectively. Ms. Yu serves as the general partner of Advaccine Investment and is entitled to exercise the voting rights attaching to Shares owned by Advaccine Investment. See “Appendix VII—Statutory and General Information” for details of our incentive scheme. Round II Investment On December 30, 2019, our Company, together with the then shareholders, entered into a capital increase agreement with Small Median Size Enterprises Development Fund (Shenzhen Limited Partnership) (中小企業發展基金(深圳有限合夥)) (“SMED”), Shanghai Lianzhi Venture Investment Management Center (Limited Partnership) (上海聯知創業投資管理中心 (有限合夥)) (“Shanghai Lianzhi”), Suzhou Hi-tech Fengqiao Emerging Industries Investment Co., Ltd. (蘇州高新楓橋新興產業投資有限公司)(“Fengqiao Investment”) and Chengdu Deshang Kuayue Equity Investment Fund Center (Limited Partnership) (成都德商跨越股權投 資基金中心(有限合夥)) (“Deshang Kuayue”, together with SMED, Shanghai Lianzhi and Fengqiao Investment, collectively, the “Round II Investors”), pursuant to which the Round II Investors agreed to subscribe the increased registered capital of our Company of RMB2,500,000 at a total consideration of RMB40,000,000 (the “Round II Investment”). The consideration was determined based on arm’s length negotiation between the parties taking into account the Company’s research and development progress, pipeline candidates, management team, future prospects and strategic needs. The following table sets forth details of the Round II Investment: Date by which the Registered capital consideration was No. Name of investors subscribed Consideration fully settled 1. SMED RMB1,250,000 RMB20,000,000 April 1, 2020 2. Shanghai Lianzhi RMB312,500 RMB5,000,000 March 9, 2020 3. Fengqiao Investment RMB562,500 RMB9,000,000 March 3, 2020 4. Deshang Kuayue RMB375,000 RMB6,000,000 March 13, 2020 – 139 – THIS DOCUMENT IS IN DRAFT FORM, INCOMPLETE AND SUBJECT TO CHANGE AND THE INFORMATION MUST BE READ IN CONJUNCTION WITH THE SECTION HEADED “WARNING” ON THE COVER OF THIS DOCUMENT HISTORY AND CORPORATE STRUCTURE Upon completion of the Round II Investment in April 2020, the registered capital of our Company was increased to RMB15,000,000 and our Company was owned as to approximately 42.50% by Ms. Yu, 14.17% by Dr. Ma, 10% by Advaccine Investment, 8.33% by Dachen Chuanglian, 8.33% by SMED, 4.17% by Stars Xuanyuan, 3.75% Fengqiao Investment, 2.50% by Heheng Investment, 2.50% by Deshang Kuayue, 2.08% by Shanghai Lianzhi and 1.67% by Taiji Investment, respectively.