Description of Business

Iterum Therapeutics plc (the Company) was incorporated under the laws of the Republic of Ireland in June 2015 as a limited company and re-registered as a public limited company on March 20, 2018. The Company maintains its registered office at 25 North Wall Quay, Dublin 1, D01 H104, Ireland. The Company commenced operations in November 2015. The Company licensed global rights to its novel anti-infective compound, sulopenem, from Pfizer Inc. (Pfizer). The Company has developed sulopenem in an oral tablet formulation, sulopenem etzadroxil-probenecid, which is referred to herein as oral sulopenem or ORLYNVAH™, as the context so requires, and is advancing the development of an IV formulation. The Company refers to sulopenem delivered intravenously as sulopenem and, sulopenem together with oral sulopenem/ORLYNVAH™, as its sulopenem program. The Company is dedicated to maximizing the commercial potential of ORLYNVAH™, the first oral branded penem available in the United States and potentially the first and only oral and intravenous (IV) branded penem available globally and is focusing the majority of its efforts and resources in preparing for the commercial launch of ORLYNVAH™ in the U.S. with its commercialization partner, EVERSANA Life Science Services, LLC (EVERSANA), which the Company expects to occur by the end of August 2025.

Commercialization Activities

The Company is continuing to build its commercial capabilities and infrastructure in anticipation of the launch of ORLYNVAH™ in the United States by the end of August 2025. In June 2025, the Company's subsidiary, Iterum Therapeutics US Limited (ITUS), entered into a Product Commercialization Agreement (the EVERSANA Agreement) with EVERSANA for the commercialization of its approved product, ORLYNVAHTM. Pursuant to the EVERSANA Agreement, EVERSANA will provide sales and commercial operations services to ITUS in the United States, as well as the provision of marketing, logistics, channel management, regulatory, medical affairs and other services related to the commercialization of ORLYNVAHTM in the United States (the Commercialization Services).

Under the terms of the EVERSANA Agreement, ITUS will have legal, regulatory, and manufacturing responsibilities for ORLYNVAHTM, and will book sales for ORLYNVAHTM. ITUS will pay EVERSANA fees and reimburse EVERSANA for its expenses in performing the Services as agreed in applicable statements of work issued pursuant to the EVERSANA Agreement. Subject to the terms and conditions of the Agreement, EVERSANA will serve as the exclusive provider to ITUS of the Commercialization Services agreed to between the parties in any statement of work issued pursuant to the EVERSANA Agreement.

Liquidity and Going Concern

Since inception, the Company has devoted substantially all of its efforts to research and development, recruiting management and technical staff, and raising capital, and has financed its operations through the issuance of ordinary and convertible preferred shares, debt raised under a financing arrangement with Silicon Valley Bank (SVB) including the Paycheck Protection Program loan (PPP loan), a sub-award from the Trustees of Boston University under the Combating Antibiotic Resistant Bacteria Biopharmaceutical Accelerator (CARB-X) program and the proceeds of a private placement (Private Placement) and subsequent rights offering (the 2020 Rights Offering) pursuant to which its wholly owned subsidiary, Iterum Therapeutics Bermuda Limited (Iterum Bermuda) issued and sold approximately $51,808 aggregate principal amount of 6.500% Exchangeable Senior Subordinated Notes (Exchangeable Notes) and $104 aggregate principal amount of Limited Recourse Royalty-Linked Subordinated Notes (the RLNs and, together with the Exchangeable Notes, the Securities), which Securities were sold in units consisting of an Exchangeable Note in the original principal amount of $1,000 and 50 RLNs (the Units). Beginning on January 21, 2021 through January 31, 2025, certain noteholders of $40,691 aggregate principal amount of Exchangeable Notes completed a non-cash exchange of their notes, including accrued and unpaid interest of $3,071, for an aggregate of 3,760,155 of the Company’s ordinary shares. On January 31, 2025, the Exchangeable Notes matured and Iterum Bermuda repaid in full to the holders thereof an aggregate principal amount of $11,117 together with accrued interest of $3,628. The Company has not generated any product revenue.

The Company is subject to risks and uncertainties common to early-stage companies in the pharmaceutical industry, including, but not limited to, the ability to secure additional capital to fund operations, failure to successfully develop and commercialize its product candidates, development by competitors of new technological innovations, dependence on key personnel, protection of proprietary technology and compliance with government regulations.

Even with receipt of U.S. Food and Drug Administration (FDA) approval, it is uncertain when, if ever, the Company will realize significant revenue from product sales.

The accompanying condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (GAAP) and include the accounts of the Company and its subsidiaries.

The Company filed a universal shelf registration statement on Form S-3 with the Securities and Exchange Commission (SEC), which was declared effective on October 17, 2022 (File No. 333-267795), and pursuant to which the Company registered for sale up to $100,000 of any combination of debt securities, ordinary shares, preferred shares, subscription rights, purchase contracts, units and/or warrants from time to time and at prices and on terms that the Company may determine. On October 7, 2022, the Company

entered into a sales agreement with HC Wainwright (the Sales Agreement), as agent, pursuant to which it could offer and sell ordinary shares, nominal value $0.01 per ordinary share (the ordinary shares) for aggregate gross sales proceeds of up to $16,000 (subject to the availability of ordinary shares), from time to time through HC Wainwright by any method permitted that is deemed to be an “at the market offering” as defined in Rule 415(a)(4) promulgated under the Securities Act of 1933, as amended (the Securities Act). On December 10, 2024, the Company filed a prospectus supplement with the SEC pursuant to which it may offer and sell ordinary shares having an aggregate offering price of up to an additional $25,000 through HC Wainwright pursuant to the Sales Agreement.

On August 9, 2024, the Company completed a rights offering (the 2024 Rights Offering) in which it sold an aggregate of 6,121,965 units (2024 Units) at a subscription price of $1.21 per whole 2024 Unit, consisting of (a) one ordinary share, (b) a warrant to purchase 0.50 ordinary shares, at an exercise price of $1.21 per whole ordinary share from the date of issuance through its expiration one year from the date of issuance (the 1-year warrants) and (c) a warrant to purchase one ordinary share, at an exercise price of $1.21 per whole ordinary share from the date of issuance through its expiration five years from the date of issuance (the 5-year warrants and, together with the 1-year warrants, the warrants). The Company's net proceeds from the 2024 Rights Offering, after deducting dealer-manager fees and other offering expenses payable by the Company, were $5,430. The warrants are exercisable upon issuance at a price of $1.21 per ordinary share. The 1-year warrants expire on August 9, 2025 and the 5-year warrants expire on August 9, 2029.

The Company filed a universal shelf registration statement on Form S-3 with the SEC, which was declared effective on February 19, 2025 (File No. 333-284774), and pursuant to which the Company registered for sale up to $150,000 of any combination of debt securities, ordinary shares, preferred shares, subscription rights, purchase contracts, units and/or warrants from time to time and at prices and on terms that the Company may determine.

On April 28, 2025, the Company entered into a securities purchase agreement with an institutional investor (the April 2025 Registered Direct Offering) pursuant to which it issued and sold an aggregate of (i) 3,040,000 ordinary shares, at a purchase price of $0.90 per ordinary share, and (ii) pre-funded warrants to purchase up to an aggregate of 2,515,556 ordinary shares at a purchase price of $0.89 per pre-funded warrant. The Company's net proceeds from the April 2025 Registered Direct Offering, after deducting placement agent fees and offering expenses payable by the Company were $4,177. Upon closing, the pre-funded warrants became exercisable immediately at an exercise price of $0.01 per ordinary share, subject to adjustment in certain circumstances, and expire when exercised in full, subject to certain conditions. As of June 30, 2025, all pre-funded warrants issued in connection with the April 28, 2025 Offering had been exercised.

In accordance with Accounting Standards Update (ASU) 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern (Subtopic 205-40), the Company has evaluated whether there are conditions and events, considered in aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern within one year of the date of issue of these quarterly condensed consolidated financial statements.

The Company has funded its operations to date primarily with proceeds from the sale of preferred shares and ordinary shares, warrants, debt raised under its financing arrangement with SVB including the PPP loan (both of which have been repaid), payments received under the CARB-X program and proceeds from the Private Placement and 2020 Rights Offering. The Company has incurred operating losses since inception, including net losses of $11,400 and $12,098 for the six months ended June 30, 2025 and 2024, respectively, and a net loss of $24,774 for the year ended December 31, 2024. The Company had an accumulated deficit of $497,472 as of June 30, 2025 and expects to continue to incur net losses for the foreseeable future. The Company’s future cash flows are dependent on key variables such as its ability to secure additional sources of funding in the form of public or private financing of debt or equity or collaboration agreements and its ability to achieve its revenue growth from sales of ORLYNVAH™ in the United States. Based on its available cash and cash equivalents, including amounts raised under the Sales Agreement with H.C. Wainwright & Co. LLC (HC Wainwright), as agent, subsequent to June 30, 2025 (see Note 18 – Subsequent Events), the Company does not have cash on hand to fund its current operations and capital expenditure requirements for the next 12 months from the date of this Quarterly Report on Form 10-Q. This condition raises substantial doubt about the Company’s ability to continue as a going concern for one year from the date these condensed consolidated financial statements are issued.

The Company's ability to continue as a going concern is dependent on its ability to obtain additional funding to support its business objectives including the revenue growth rate of ORLYNVAH™ following commercialization, which the Company expects to occur by the end of August 2025. The Company has limited experience and has not yet demonstrated an ability to successfully commercialize a product. Management expects that, in order to obtain additional funding for its operations and commercialization activities, it will need to raise funding through the possible sale of the Company’s equity or debt through additional public or private financings. Although management plans to obtain additional funding to finance its operations, and has successfully raised capital in the past, there is no assurance that we will be successful in obtaining sufficient funding on terms acceptable to us to fund continuing operations, if at all.

If the Company is unable to obtain funding, it could be forced to significantly delay, scale back or discontinue the development and commercialization of its sulopenem program, or otherwise change its strategy, which could adversely affect its business prospects, or the Company may be unable to continue operations. Based on the Company’s operating losses since inception, the expectation of continued operating losses for the foreseeable future, and the need to raise additional capital to finance its future operations,

management has concluded there is substantial doubt about the Company’s ability to continue as a going concern within one year from the date these condensed consolidated financial statements are issued.

The accompanying condensed consolidated financial statements do not include any adjustments that might result from the outcome of this uncertainty. Accordingly, the condensed consolidated financial statements have been prepared on a basis that assumes the Company will continue as a going concern and which contemplates the realization of assets and satisfaction of liabilities and commitments in the ordinary course of business.

Interim Financial Information

The condensed consolidated balance sheet at December 31, 2024 was derived from audited financial statements, but does not include all disclosures required by GAAP. The accompanying unaudited condensed consolidated financial statements as of June 30, 2025 and for the three and six months ended June 30, 2025 and 2024 have been prepared by the Company pursuant to the rules and regulations of the SEC for interim financial statements. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. These condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto for the year ended December 31, 2024, included in the Company’s Annual Report on Form 10-K filed with the SEC on February 7, 2025. In the opinion of management, all adjustments, consisting only of normal recurring adjustments necessary for a fair statement of the Company’s financial position as of June 30, 2025, and results of operations for the three and six months ended June 30, 2025 and 2024, and cash flows for the six months ended June 30, 2025 and 2024 have been made. The results of operations for the three and six months ended June 30, 2025 are not necessarily indicative of the results of operations that may be expected for the year ending December 31, 2025.