Financial Position - Estimated cash and cash equivalents of approximately $76.3 million as of September 30, 2024[2] - Existing cash and cash equivalents expected to fund operating expenses and capital expenditures into mid-2026[5] Workforce and Restructuring - Company announced a workforce reduction of approximately 39% to refocus on strategic priorities around tebipenem HBr and R&D efforts[4] - Estimated restructuring charges of approximately $1.1 million related to severance pay and termination benefits[5] - Company may incur additional costs related to the workforce reduction not currently contemplated[5] Business Operations and Strategy - Company released an investor presentation providing updates on business and operations[6] - Company emphasizes reliance on third parties for manufacturing and commercialization of product candidates[11] Forward-Looking Statements - Forward-looking statements indicate potential regulatory delays and the need for additional funding[9] - Anticipated expenses and cash runway are subject to various important factors that may affect actual results[9] - Completion of quarterly results will be included in the Company's Quarterly Report on Form 10-Q for the quarter ended September 30, 2024[3]

Core Viewpoint - Spero Therapeutics is progressing well with its Phase 3 PIVOT-PO trial of tebipenem HBr, expecting to complete enrollment in the second half of 2025, while also managing its financial resources effectively to extend its cash runway into mid-2026 [1][2][10]. Pipeline Update - Tebipenem HBr is an investigational oral carbapenem antibiotic aimed at treating complicated urinary tract infections (cUTI), potentially reducing hospitalizations [3][4]. - The PIVOT-PO trial is a randomized, double-blinded study comparing oral tebipenem HBr with intravenous imipenem cilastatin, targeting approximately 2,648 patients [4]. - SPR206 is another investigational drug showing activity against multi-drug resistant Gram-negative pathogens, with plans for a Phase 2 trial pending funding [5][6]. Financial Results - For Q3 2024, Spero reported a net loss of $17.1 million, or ($0.32) per share, compared to a net loss of $3.2 million, or ($0.06) per share in Q3 2023 [10][18]. - Total revenue for Q3 2024 was $13.5 million, down from $25.5 million in Q3 2023, primarily due to lower collaboration revenues [10][18]. - Research and development expenses increased to $26.9 million in Q3 2024 from $16.4 million in the same period in 2023, attributed to higher clinical trial costs [10][18]. Corporate Update - Following the suspension of the SPR720 development program, Spero underwent a restructuring that included a 39% reduction in workforce, which has extended its cash runway into mid-2026 [9][10].

Financial Position - As of September 30, 2024, the company had an accumulated deficit of $438.8 million and cash and cash equivalents of $76.3 million[158]. - As of September 30, 2024, the company had cash and cash equivalents of $76.3 million, which is expected to fund operating expenses and capital requirements for at least 12 months[192]. - The company anticipates needing additional funding beyond the 12-month period, which may include equity or debt financings, new collaborations, or grant funding[192]. Revenue and Income - The company has not generated any revenue from product sales to date and cannot predict future revenue generation from product commercialization[167]. - Total revenues for the three months ended September 30, 2024, were $13.5 million, a decrease of $12.0 million compared to $25.5 million in the same period of 2023[177]. - Grant revenue for the three months ended September 30, 2024, was $5.7 million, an increase of $3.6 million from $2.1 million in the same period of 2023[177]. - Collaboration revenue from related parties decreased by $15.4 million to $7.8 million in the three months ended September 30, 2024, compared to $23.4 million in 2023[178]. - For the nine months ended September 30, 2024, total revenues were $32.9 million, an increase of $2.7 million from $30.3 million in 2023[181]. - Grant revenue for the nine months ended September 30, 2024, was $14.9 million, an increase of $9.5 million from $5.3 million in 2023[181]. - The company recognized $14.6 million in grant revenue from the BARDA contract for tebipenem HBr during the nine months ended September 30, 2024, an increase of $11.5 million from $3.1 million in 2023[181]. - Collaboration revenue for the nine months ended September 30, 2024, was $18.0 million, a decrease of $6.87 million from $24.9 million in the same period of 2023[182]. - The company recognized $17.7 million in collaboration revenue from GSK and $0.3 million from Pfizer for the nine months ended September 30, 2024[182]. Expenses - The company expects to incur significant expenses and increasing operating losses for at least the next several years[158]. - Research and development expenses primarily consist of costs related to drug discovery and development, with significant external costs tracked on a program-by-program basis[168]. - Research and development expenses increased by $10.5 million to $26.9 million for the three months ended September 30, 2024, compared to $16.4 million in 2023[179]. - Research and development expenses totaled $67.9 million for the nine months ended September 30, 2024, an increase of $33.04 million compared to $34.9 million for the same period in 2023[183]. - Direct costs for the tebipenem HBr program increased by $30.5 million during the nine months ended September 30, 2024, due to ongoing clinical activities[185]. - Total operating expenses for the three months ended September 30, 2024, were $32.1 million, an increase of $4.7 million from $27.4 million in 2023[177]. - General and administrative expenses decreased to $16.6 million for the nine months ended September 30, 2024, down by $2.47 million from $19.1 million in 2023[186]. Losses - The net loss for the three months ended September 30, 2024, was $17.1 million, an increase of $13.9 million from a net loss of $3.2 million in the same period of 2023[177]. - Net cash used in operating activities for the nine months ended September 30, 2024, was less than $0.1 million, compared to $15.5 million for the same period in 2023[188]. Strategic Restructuring - The strategic restructuring announced on October 29, 2024, included a workforce reduction of approximately 39%, with estimated costs of $1.1 million related to severance and termination benefits[160]. - The company anticipates a substantial reduction in future development-related expenses following the suspension of SPR720 and the implementation of its restructuring[173]. - The company plans to make reductions in spending if adequate additional funding is not secured, which may delay or eliminate planned clinical trials and research programs[192]. Clinical Development - The Phase 3 clinical trial for tebipenem HBr is on track, targeting enrollment of approximately 2,648 patients, with completion expected in the second half of 2025[163]. - An additional contract modification of $11.7 million was executed under the existing contract with BARDA, increasing total committed funding to $59.3 million for tebipenem HBr clinical development[164]. - The FDA cleared the investigational new drug application for SPR206, with plans to initiate a Phase 2 trial pending non-dilutive funding availability[165]. Future Outlook - Future cash requirements will depend on clinical trial costs, regulatory approvals, and potential collaborations[191]. - The company has no material changes to its contractual obligations and commitments during the three and nine months ended September 30, 2024[194]. - There are currently no off-balance sheet arrangements affecting the company[195]. - The primary objectives of the company's investment activities are to preserve principal, provide liquidity, and maximize income without significantly increasing risk[195]. - The company faces exposure to foreign currency exchange rate movements, primarily with the Euro, British Pound, Japanese Yen, and Australian Dollar against the U.S. dollar[195]. - Historically, foreign currency fluctuations have not had a material impact on the company's consolidated financial statements[195]. - The company does not have any assets classified as marketable securities as of September 30, 2024[195]. - The company is classified as a smaller reporting company and is not required to provide certain disclosures under SEC rules[195].

CAMBRIDGE, Mass., July 29, 2024 (GLOBE NEWSWIRE) -- Spero Therapeutics, Inc. (Nasdaq: SPRO), a multi-asset clinical-stage biopharmaceutical company, focused on identifying and developing novel treatments for rare diseases and multi-drug resistant (MDR) bacterial infections, today announced that management will host a conference call and live audio webcast on Monday August 5th, 2024 at 4:30 p.m. ET to report financial results for second quarter 2024 and provide an update on its business and pipeline. To acce ...

Exhibit 99.1 Spero Therapeutics Announces First Quarter 2024 Operating Results and Provides a Business Update CAMBRIDGE, Mass., May 15, 2024 — Spero Therapeutics, Inc. (Nasdaq: SPRO), a multi-asset clinical-stage biopharmaceutical company, focused on identifying and developing novel treatments for rare diseases and multi-drug resistant (MDR) bacterial infections, today announced financial and operational results for the quarter ended March 31, 2024. "We continued to make progress towards our stated goals ac ...

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, 2024 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: 001-38266 SPERO THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) (State or other jurisdiction of incorpora ...

Spero Therapeutics, Inc. (NASDAQ:SPRO) Q4 2023 Earnings Conference Call March 13, 2024 4:30 PM ET Company Participants Michael Wood - Managing Director of LifeSci Advisors Sath Shukla - CEO Kamal Hamed - CMO Esther Rajavelu - CFO and Chief Business Officer Conference Call Participants Ritu Baral - TD Cowen Louise Chen - Cantor Operator Good afternoon and welcome to the Spero Therapeutics Full Year 2023 Financial Results Conference Call. At this time, all participants are in a listen-only mode. Following the ...

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, 2023 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 001-38266 SPERO THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) Delaware 46-4590683 State or other juri ...

Spero Therapeutics, Inc. (NASDAQ:SPRO) Q3 2023 Earnings Conference Call November 13, 2023 4:30 PM ET Company Participants Ted Jenkins - Vice President, Investor Relations and Strategic Finance Sath Shukla - Chief Executive Officer Kamal Hamed - Chief Medical Officer Steve Dipalma - Interim Chief Financial Officer and Treasurer Conference Call Participants Louise Chen - Cantor Fitzgerald Boobalan Pachaiyappan - H.C. Wainwright Good afternoon and welcome to the Spero Therapeutics Third Quarter 2023 Financial ...

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 September 30, 2023 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: 001-38266 SPERO THERAPEUTICS, INC. (Exact name of registrant as specified in its charter) | Delaware | 46-4590683 | | --- | --- ...