Organization and Significant Accounting Policies	6 Months Ended
Jun. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Significant Accounting Policies	1. Organization and Significant Accounting Policies Nature of Operations Phio Pharmaceuticals Corp. (“Phio” or the “Company”) is a clinical stage biotechnology company whose proprietary INTASYL™ self-delivering RNAi technology platform is designed to make immune cells more effective in killing tumor cells. Phio is developing therapeutics that are designed to leverage INTASYL to precisely target specific proteins that reduce the body’s ability to fight cancer, without the need for specialized formulations or drug delivery systems. Effective January 26, 2023, the Company completed a 1-for-12 reverse stock split of the Company’s outstanding common stock, including reclassifying an amount equal to the reduction in par value to additional paid-in capital. The reverse stock split did not reduce the number of authorized shares of the Company’s common or preferred stock. All share and per share amounts have been adjusted to give effect to the reverse stock split. Principles of Consolidation The condensed consolidated financial statements include the accounts of Phio and its wholly-owned subsidiary, MirImmune, LLC. All material intercompany accounts have been eliminated in consolidation. Basis of Presentation The accompanying condensed consolidated financial statements are unaudited and have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”). Certain information and footnote disclosures that are included in the Company’s annual consolidated financial statements, but that are not required for interim reporting purposes, have been condensed or omitted. Additionally, the Company made adjustments to the outstanding stock option and unvested restricted stock unit balances, and related per share amounts, at December 31, 2022 to reflect final revisions to these outstanding equity awards as a result of the Company’s reverse stock split. The adjustment had no effect on the Company’s condensed consolidated financial statements. These statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in the Company’s most recent Annual Report on Form 10-K for the year ended December 31, 2022, as filed with the Securities and Exchange Commission (the “SEC”) on March 22, 2023 (the “2022 Form 10-K”). In the opinion of management, all adjustments (including normal recurring accruals) considered necessary for a fair presentation of the condensed consolidated financial statements have been included. Interim results are not necessarily indicative of results for a full year. Use of Estimates The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. The areas subject to significant estimates and judgement include, among others, those related to the fair value of equity awards, accruals for research and development expenses, useful lives of property and equipment, income taxes, and the valuation allowance on the Company’s deferred tax assets. On an ongoing basis the Company evaluates its estimates and bases its estimates on historical experience and other relevant assumptions that the Company believes are reasonable under the circumstances. Actual results could differ materially from these estimates. Liquidity The Company has reported recurring losses from operations since inception and expects to continue to have negative cash flows from operations for the foreseeable future. Historically, the Company’s primary source of funding has been from sales of its securities. The Company’s ability to continue to fund its operations is dependent on obtaining funding from third parties, such as proceeds from the issuance of debt, sale of equity, or strategic opportunities, in order to maintain its operations. This is dependent on a number of factors, including the market demand or liquidity of the Company’s common stock. There is no guarantee that debt, additional equity or other funding will be available to the Company on acceptable terms, or at all. If the Company fails to obtain additional funding when needed, the Company would be forced to scale back or terminate its operations or seek to merge with or to be acquired by another company. The Company has limited cash resources, has reported recurring losses from operations since inception and has not yet received product revenues. These factors raise substantial doubt regarding the Company’s ability to continue as a going concern, and the Company’s current cash resources may not provide sufficient capital to fund operations for at least the next 12 months from the date of the release of these financial statements. The continuation of the Company as a going concern depends upon the Company’s ability to raise additional capital through an equity offering, debt offering and/or strategic opportunity to fund its operations. There can be no assurance that the Company will be successful in accomplishing these plans in order to continue as a going concern. These financial statements do not include any adjustments to the recoverability and classification of recorded asset amounts and classification of liabilities that might be necessary should the Company be unable to continue as a going concern. Summary of Significant Accounting Policies There have been no material changes to the significant accounting policies disclosed in the Company’s 2022 Form 10-K. Recent Accounting Pronouncements There have been no recent accounting pronouncements that have significantly impacted this Quarterly Report on Form 10-Q, beyond those disclosed in the Company’s 2022 Form 10-K.

Organization and Significant Accounting Policies

6 Months Ended

Jun. 30, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Organization and Significant Accounting Policies

1. Organization and Significant Accounting Policies

Nature of Operations

Phio Pharmaceuticals Corp. (“Phio” or the “Company”) is a clinical stage biotechnology company whose proprietary INTASYL™ self-delivering RNAi technology platform is designed to make immune cells more effective in killing tumor cells. Phio is developing therapeutics that are designed to leverage INTASYL to precisely target specific proteins that reduce the body’s ability to fight cancer, without the need for specialized formulations or drug delivery systems.

Effective January 26, 2023, the Company completed a 1-for-12 reverse stock split of the Company’s outstanding common stock, including reclassifying an amount equal to the reduction in par value to additional paid-in capital. The reverse stock split did not reduce the number of authorized shares of the Company’s common or preferred stock. All share and per share amounts have been adjusted to give effect to the reverse stock split.

Principles of Consolidation

The condensed consolidated financial statements include the accounts of Phio and its wholly-owned subsidiary, MirImmune, LLC. All material intercompany accounts have been eliminated in consolidation.

Basis of Presentation

The accompanying condensed consolidated financial statements are unaudited and have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”). Certain information and footnote disclosures that are included in the Company’s annual consolidated financial statements, but that are not required for interim reporting purposes, have been condensed or omitted. Additionally, the Company made adjustments to the outstanding stock option and unvested restricted stock unit balances, and related per share amounts, at December 31, 2022 to reflect final revisions to these outstanding equity awards as a result of the Company’s reverse stock split. The adjustment had no effect on the Company’s condensed consolidated financial statements. These statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in the Company’s most recent Annual Report on Form 10-K for the year ended December 31, 2022, as filed with the Securities and Exchange Commission (the “SEC”) on March 22, 2023 (the “2022 Form 10-K”). In the opinion of management, all adjustments (including normal recurring accruals) considered necessary for a fair presentation of the condensed consolidated financial statements have been included. Interim results are not necessarily indicative of results for a full year.

Use of Estimates

The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. The areas subject to significant estimates and judgement include, among others, those related to the fair value of equity awards, accruals for research and development expenses, useful lives of property and equipment, income taxes, and the valuation allowance on the Company’s deferred tax assets. On an ongoing basis the Company evaluates its estimates and bases its estimates on historical experience and other relevant assumptions that the Company believes are reasonable under the circumstances. Actual results could differ materially from these estimates.

Liquidity

The Company has reported recurring losses from operations since inception and expects to continue to have negative cash flows from operations for the foreseeable future. Historically, the Company’s primary source of funding has been from sales of its securities. The Company’s ability to continue to fund its operations is dependent on obtaining funding from third parties, such as proceeds from the issuance of debt, sale of equity, or strategic opportunities, in order to maintain its operations. This is dependent on a number of factors, including the market demand or liquidity of the Company’s common stock. There is no guarantee that debt, additional equity or other funding will be available to the Company on acceptable terms, or at all. If the Company fails to obtain additional funding when needed, the Company would be forced to scale back or terminate its operations or seek to merge with or to be acquired by another company.

The Company has limited cash resources, has reported recurring losses from operations since inception and has not yet received product revenues. These factors raise substantial doubt regarding the Company’s ability to continue as a going concern, and the Company’s current cash resources may not provide sufficient capital to fund operations for at least the next 12 months from the date of the release of these financial statements. The continuation of the Company as a going concern depends upon the Company’s ability to raise additional capital through an equity offering, debt offering and/or strategic opportunity to fund its operations. There can be no assurance that the Company will be successful in accomplishing these plans in order to continue as a going concern. These financial statements do not include any adjustments to the recoverability and classification of recorded asset amounts and classification of liabilities that might be necessary should the Company be unable to continue as a going concern.

Summary of Significant Accounting Policies

There have been no material changes to the significant accounting policies disclosed in the Company’s 2022 Form 10-K.

Recent Accounting Pronouncements

There have been no recent accounting pronouncements that have significantly impacted this Quarterly Report on Form 10-Q, beyond those disclosed in the Company’s 2022 Form 10-K.