Spero Therapeutics, Inc.

Good afternoon and welcome to Sparrow Therapeutics second quarter 2025 earnings conference call. At this time, all participants are in the listen-only mode. Following the company's formal remark, we will open up the call for questions. Please be advised that this call is being recorded and a replay will be available. You can find the information in the replay and further information related to today's announcement on the Sparrow Therapeutics website at www.sperrotherapeutics.com. At this time, I would like to turn the call over to Shahi Biran, Senior Director, Investor Relations. Mr. Biran, please go ahead.

Thank you, Operator, and thank you all for participating in today's conference call. This afternoon, Sparrow Therapeutics released financial results and provided a business update for the second quarter of 2025. The press release is available on the investor page of the Sparrow Therapeutics website. Before we begin, I would like to remind you that some of the information presented on this conference call contains forward-looking statements under the Private Securities Litigation Reform Act of 1995 as amended. These forward-looking statements are based on management's current expectations and beliefs and are subject to risks, uncertainties, and other factors that may cause actual results to differ materially from those indicated by such forward-looking statements. These risks uncertainties, and other factors are described in detail in Sphero-Therapeutics filings with the SEC, including in the risk factors set forth in the periodic report on Form 10-Q for the second quarter ended June 30, 2025, filed with the SEC today. Leading our call today will be Esther Rajavelu, our Chief Executive Officer and Chief Financial Officer. She will be joined by our Chief Operating Officer, Tim Koitzer. Esther will provide an update on our lead clinical program, Tevipenem HBR, for complicated urinary tract infections, or COTIs. Then, Tim will provide an overview of the COTI therapeutic landscape and the unmet need we believe Tevipenem HBR could fill, followed by a brief update on SPR 720. Esther will then conclude with a review of our financials before opening the call for questions. I will now turn the call over to Esther.

Thank you, Shai. Good afternoon, everyone, and thank you for joining our second quarter 2025 earnings and business update call. I'm very pleased to share that in May of this year, together with our development partner, GSK, We announced that the Phase III PIVOT-PO trial evaluating tebupenem HVR in patients with CUTI, including pyelonephritis, successfully met its primary endpoint and was stopped early for efficacy. This decision follows a recommendation from the Independent Data Monitoring Committee, or IDMC, which reviewed data from a pre-specified interim analysis based on 1,690 patients enrolled in the trial. The primary endpoint was overall response at the test of cure visit, a composite of clinical cure plus microbiological eradication. Tebupenem HBR demonstrated non-inferiority to intravenous imipenem psilostatin in hospitalized adult patients with CUTI, including pyelonephritis. The positive outcome from the PIVOT-PO trial further supports our thesis that tebupenem HBR and oral carbapenem can deliver comparable treatment outcomes to standard-of-care IV carbapenem therapy. The ID&C review did not identify any new safety concerns beyond what had been reported in prior carbapenem studies. Diarrhea and headache were the two most reported adverse events. We and GSK plan to submit the full results from Pivot-PO for presentation at an upcoming scientific conference and for publication in a peer-reviewed journal. GSK is responsible for regulatory filings and has communicated that they plan to work with the FDA to include the PIVOT PO data as part of an FDA filing at ERN 2025. We currently believe that FDA action is likely in the second half of 2026. Sparrow will support GSK in the preparation of the filing and any potential pre-approval communications with the FDA. The PivotPO study is covered by the Special Protocol Assessment Agreement entered into with the FDA in 2023. The FDA has indicated that positive and persuasive results from the PivotPO, together with results from previously completed studies, could be sufficient to support approval of tebupenem-HBR as a treatment for CUTIs, including pyelonephritis, for a limited use indication. As a reminder, our agreement with GSK grants them an exclusive license to develop and commercialize tebupenem-HBR in all territories except for Japan and certain other Asian countries that are covered by our partnership with Meiji Seika Pharmaco. While Sparrow is responsible for the execution and cost of the PIVOT-PO trial, GSK is responsible for the execution and cost of the planned regulatory filings and commercialization activities, as well as any future clinical development activities. Assuming these activities are successfully pursued, Sparrow could qualify for up to 351 million in contingent milestones, including 25 million when GSK submits the U.S. regulatory filing. and subsequent milestones based on commercialization and sales ramp, as well as tiered royalties on net sales. Our press release and 10-Q filed this evening include additional details on these contingent payments. Importantly, with the trial stopping early for efficacy, we have achieved meaningful cost savings in the near term, which we anticipate will extend our cash runway into 2028 based on our current operating plan. I will now turn the call over to Tim, who will provide additional details on the TEBI program and FPR 720.