FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 For the fiscal year ended December 31, 2021 Or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 001-36304 PHIO PHARMACEUTICALS CORP. (Exact name of registrant as specified in its charter) | Title of each class | Tra ...

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to For the quarterly period ended September 30, 2021 OR Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Commission File Number: 001-36304 Phio Pharmaceuticals Corp. (Exact name of registrant as specified in its charter) Delaware 45-3215903 (State o ...

DEVELOPING THE NEXT GENERATION of immuno-oncology therapeutics w w w.phiopharma.com I Ticker: PHIO (NASDAQ) September 2021 Forward Looking Statements This presentation contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Words such as "believes," "anticipates," "plans," "expects," "indicates," "will," "intends," "potential," "suggests" and similar expressions are intended to identify forward-looking statements. These statements are based on Phio Pha ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2021 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-36304 Phio Pharmaceuticals Corp. (Exact name of registrant as specified in its charter) Delaware 45-3215903 (State of inc ...

OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-36304 Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2021 Phio Pharmaceuticals Corp. (Exact name of registrant as specified in its charter) Delaware 45-3215903 ( ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2020 Or (508) 767-3861 ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number 001-36304 PHIO PHARMACEUTICALS CORP. (Exact name of registrant as specified in its charter) (State or ot ...

DEVELOPING THE NEXT GENERATION of immuno-oncology therapeutics www.phiopharma.com I Ticker: PHIO (NASDAQ) January 2020 Forward Looking Statements This presentation contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Words such as "believes," "anticipates," "plans," "expects," "indicates," "will," "intends," "potential," "suggests" and similar expressions are intended to identify forward-looking statements. These statements are based on Phio Pharmac ...

DEVELOPING THE NEXT GENERATION of immuno-oncology therapeutics September 2019 www.phiopharma.com I Ticker: PHIO (NASDAQ) Forward Looking Statements This presentation contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Words such as "believes," "anticipates," "plans," "expects," "indicates," "will," "intends," "potential," "suggests" and similar expressions are intended to identify forward-looking statements. These statements are based on Phio Pharm ...