Phoenix Biotech Acquisition Corp. (PBAXU) is a blank check company, or special purpose acquisition company (SPAC), focused on effecting a merger, share exchange, asset acquisition, share purchase, reorganization, or similar business combination with one or more businesses, primarily targeting the healthcare and healthcare-related industries in the United States and Europe; it offers no current products or services beyond its SPAC structure, which includes Class A common stock and warrants traded as units on Nasdaq. Incorporated in 2021 and headquartered in Oakland, California, the company completed its initial public offering in October 2021, raising $155 million through 15.5 million units priced at $10 each. In February 2024, Phoenix Biotech Acquisition Corp. completed a business combination with CERo Therapeutics, Inc., a clinical-stage immunotherapy company developing engineered T cell therapeutics such as its lead candidate CER-1236 for hematologic malignancies and solid tumors, resulting in the combined entity operating as CERo Therapeutics Holdings, Inc. (NASDAQ: CERO) with CERo surviving as a wholly-owned subsidiary; post-merger, PBAXU units were suspended from trading on Nasdaq, and the ticker now reflects limited or delisted status as of late 2025.