X0306 4 2022-03-01 0 0001533040 Phio Pharmaceuticals Corp. PHIO 0001570511 Kontulis Caitlin C/O PHIO PHARMACEUTICALS CORP. 257 SIMARANO DRIVE, SUITE 101 MARLBOROUGH MA 01752 0 1 0 0 Secretary & VP Finance & Admin Common stock, $0.0001 par value 2022-03-01 4 F 0 4011 0.821 D 103815 D The transaction reported represents the withholding of shares by the issuer to satisfy the reporting person's tax withholding obligations in connection with the vesting of restricted stock units. No shares were sold. Includes shares of common stock underlying unvested restricted stock units. Caitlin Kontulis 2022-03-03