Yisheng Biopharma Co., Ltd. executed a letter of intent to acquire Summit Healthcare Acquisition Corp. (NasdaqCM:SMIH) from Summit Healthcare Acquisition Sponsor LLC and others in a reverse merger transaction on July 1, 2022. Yisheng Biopharma Co., Ltd. agreed to acquire Summit Healthcare Acquisition Corp. (NasdaqCM:SMIH) from Summit Healthcare Acquisition Sponsor LLC and others in a reverse merger transaction on September 29, 2022. Upon closing of the Transaction, YS Biopharma will continue to be led by Mr. Yi Zhang, its founder and chairman, Dr. Hui Shao, its president and chief executive officer, and the current management team. Upon closing of the Business Combination, Mr. Bo Tan, the Chief Executive Officer, Co-Chief Investment Officer, and director of Summit, will join YS Biopharma's board of directors. The board of directors of YS Biopharma will consist of seven directors, including two current directors of YS Biopharma, Bo Tan, and four independent directors. YS Biopharma shareholders will become the majority owners immediately after the closing of the transaction and the combined company will be renamed as YS Biopharma Co., Ltd. YS Biopharma will remain as the combined company and its shares and warrants are expected to begin trading on the Nasdaq Capital Market under the symbols “YS” and “YSBPW,” respectively. The business combination is expected to provide up to approximately $230 million in gross proceeds to YS Biopharma, including $30 million from Forward Purchase Investors and up to approximately $200 million currently held in Summit's. Each of the board of directors of YS Biopharma and Summit has unanimously approved the proposed Transaction. Completion of the proposed Transaction is still subject to the approval of Summit's shareholders and certain other customary closing conditions, the approval by the Nasdaq Stock Market LLC on the listing application of the combined company. Proceeds from the Transaction will allow YS Biopharma to fund its ongoing and planned clinical trials, future commercial launch of PIKA® adjuvanted rabies vaccine, the construction of new GMP-compliant manufacturing plants as well as developing other product candidates. As of February 9, 2023, the Company announced that the Securities and Exchange Commission (the “SEC”) has declared the effectiveness of YS Biopharma's registration statement on Form F-4 (the “Registration Statement”) in connection with the deal. The Company has decided to reschedule the Extraordinary General Meeting from March 1, 2023 to March 14, 2023. As of March 14, 2023, the transaction is approved by the shareholders of Summit. The Transaction is targeted to be completed in the first quarter of 2023. As of March 14, 2023, the transaction is expected to close on March 16, 2023. Jingtian & Gongcheng and Maples and Calder (Hong Kong) LLP and Dan Ouyang, Ke Li and Myra Sutanto Shen of Wilson Sonsini Goodrich & Rosati acted as a legal advisor to Yisheng Biopharma Co., Ltd. Cooley LLP and Ogier acted as a legal advisor to Summit Healthcare Acquisition. Continental Stock Transfer & Trust Company acted as transfer agent to Summit Healthcare Acquisition. ValueScope, Inc. acted as financial advisor and fairness opinion provider with a service fee of $45,000 respectively to Summit Healthcare Acquisition. Summit has engaged Advantage Proxy, Inc. to assist in the solicitation of proxies and agreed to pay Advantage a fixed fee of $10,000.

Yisheng Biopharma Co., Ltd. completed the acquisition of Summit Healthcare Acquisition Corp. (NasdaqCM:SMIH) from Summit Healthcare Acquisition Sponsor LLC and others in a reverse merger transaction on March 16, 2023.