YS Biopharma, a biopharmaceutical company, agreed to go public via a SPAC merge with Summit Healthcare Acquisition, a blank check company, in an $834m deal. "YS Biopharma has always been the trailblazer and at the forefront in developing new technology and products for vaccine and immunological therapeutics. This transaction will fuel our strategy for future business expansion and execution and allow shareholders to participate in significant upside potential created by the partnership with Summit," Yi Zhang, YS Biopharma Founder and Chairman.