As filed with the U.S. Securities and Exchange Commission on December 22, 2025 Registration No. UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 ____________________________ ESTRELLA IMMUNOPHARMA, INC. (Exact Name of Registrant as Specified in its Charter) ____________________________ (State or other jurisdiction of incorporation or organization) (Primary Standard Industrial Classification Code Number) Delaware 6770 86-1 ...

Group 1 - Mustang Bio, Inc. has regained compliance with Nasdaq's minimum stockholders' equity requirement as per Nasdaq Listing Rule 5550(b)(1) [1][2] - The company previously satisfied the minimum bid price requirement under Nasdaq Listing Rule 5550(a)(2) for continued listing, thus meeting all Nasdaq Capital Market listing requirements [2] - Mustang Bio is a clinical-stage biopharmaceutical company focused on developing cell therapies for difficult-to-treat cancers, aiming to license or acquire technologies to fund research and development [3] Group 2 - Mustang Bio has partnered with leading medical institutions to advance CAR-T therapies [3] - The company's common stock is registered under the Securities Exchange Act of 1934 and it files periodic reports with the SEC [3]