Registration No. 333- As filed with the Securities and Exchange Commission on May 17, 2024 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM S-3 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 Phio Pharmaceuticals Corp. (Exact name of registrant as specified in its charter) Delaware 45-3215903 (State or other jurisdiction of incorporation or organization) (I.R.S. Employer Identification No.) 11 Apex Drive, Suite 300A, PMB 2006 Marlborough, Massachusetts 01752 (508) 767-386 ...