Phio Pharmaceuticals Reports Third Quarter 2020 Financial Results and Provides Business Update Marlborough, Mass.

Pharmaceuticals Reports Third Quarter 2020 Financial Results and Provides Business Update

Marlborough, Mass., November 10, 2020

-- Phio Pharmaceuticals Corp. (Nasdaq: PHIO), a biotechnology company developing the next generation of immuno-oncology therapeutics

based on its proprietary self-delivering RNAi (INTASYL ) therapeutic platform, today reported its financial results for the

quarter ended September 30, 2020 and provided a business update.

"During the quarter, we continued to execute on the development

of our INTASYL RNAi technology as a cancer immunotherapy platform for innovative therapeutics. Promising new in vivo data

was recently presented at the Society for Immunotherapy of Cancer's (SITC) annual meeting. This data showed that our INTASYL

compounds targeting PD-1, PD-L1 or TIGIT inhibited tumor growth, and that such antitumoral effect can be significantly improved

by combining different INTASYL compounds without having a negative impact on the tolerability of the treatment," said Dr.

Gerrit Dispersyn, President and CEO of Phio. "Immune checkpoint therapy with systemic antibodies can result in dose limiting

toxicities, especially when used in combination. With our INTASYL platform, we can easily combine multiple targets in a single

therapeutic. Our data suggest that local administration with INTASYL compounds, even when used in combination, may provide a safer

and more cost-effective alternative to antibody-based immune checkpoint therapy. Based upon these exciting results, we look forward

to finalizing our IND-enabling studies and to moving our INTASYL compounds into the clinical phase of development in the near future."

Quarter in Review and Recent Corporate Updates

At September 30, 2020, the Company

had cash of $16.9 million as compared with $6.9 million at December 31, 2019. The Company expects its cash will be sufficient to

fund currently planned operations for at least the next 12 months.

Research and Development Expenses

Research and development expenses were

approximately $1.3 million for the quarter ended September 30, 2020, compared to approximately $1.0 million for the quarter ended

September 30, 2019. The increase is primarily due to an increase in the use of third-party service providers to conduct preclinical

research studies to support the development of the Company's pipeline programs as compared to the prior year period offset by a

decrease in the use of an outside interim temporary labor consultant in the prior year period.

General and Administrative Expenses

General and administrative expenses

were relatively steady at $1.1 million for the three-month periods ended September 30, 2020 and 2019.

Net loss was $2.3 million, or $0.40

per share, for the quarter ended September 30, 2020, compared with $2.1 million, or $4.53 per share, for the quarter ended September

30, 2019. The increase in net loss was primarily attributable to an increase in research and development expenses, as discussed

above. The change in net loss per share was primarily due to an increase in the number of shares outstanding as a result of our

capital raise activities as compared to the prior year period.

Pharmaceuticals Corp.

Phio Pharmaceuticals Corp. (Nasdaq: PHIO) is a biotechnology

company developing the next generation of immuno-oncology therapeutics based on its self-delivering RNAi (INTASYL ) therapeutic

platform. The Company's efforts are focused on silencing tumor-induced suppression of the immune system through its proprietary

INTASYL platform with utility in immune cells and the tumor micro-environment. Our goal is to develop powerful INTASYL therapeutic

compounds that can weaponize immune effector cells to overcome tumor immune escape, thereby providing patients a powerful new treatment

option that goes beyond current treatment modalities. For additional information, visit the Company's website, www.phiopharma.com.

Forward Looking Statements

This press release contains forward-looking statements within

the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements are neither historical facts nor

assurances of future performance. These statements are based only on our current beliefs, expectations and assumptions regarding

the impact to our business and operations by the recent coronavirus outbreak, results from our preclinical and clinical activities,

the development of our product candidates, the ability of obtain future financing, the future of our business, future plans and

strategies, projections, anticipated events and trends, the economy and other future conditions. Because forward-looking statements

relate to the future, they are subject to inherent uncertainties, risks and changes in circumstances that are difficult to predict

and many of which are outside of our control. Our actual results may differ materially from those indicated in the forward-looking

statements as a result of a number of important factors, including, but not limited to, market and other conditions and those identified

in our Annual Report on Form 10-K and subsequent Quarterly Reports on Form 10-Q under the caption "Risk Factors" and

in other filings the Company periodically makes with the SEC. Readers are urged to review these risk factors and to not act in

reliance on any forward-looking statements, as actual results may differ from those contemplated by our forward-looking statements.

Phio does not undertake to update forward-looking statements to reflect a change in its views, events or circumstances that occur

after the date of this release, except as required by law.

Contact Phio Pharmaceuticals Corp.

PHIO PHARMACEUTICALS CORP.

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS

(Amounts in thousands, except share and per share data)

PHIO PHARMACEUTICALS CORP.

CONDENSED CONSOLIDATED BALANCE SHEETS

(Amounts in thousands)