Core Viewpoint - Spero Therapeutics reported significant progress in its tebipenem HBr program, with the Phase 3 PIVOT-PO trial meeting its primary endpoint, indicating potential for a new standard of care in treating complicated urinary tract infections (cUTI) [2][6][7]. Financial Results - For Q2 2025, Spero reported a net loss of $1.7 million, a significant reduction from a net loss of $17.9 million in Q2 2024, translating to a diluted net loss per share of $0.03 compared to $0.33 in the previous year [17][20]. - Total revenue for Q2 2025 was $14.2 million, up from $10.2 million in Q2 2024, primarily driven by collaboration revenue from GSK [17][20]. - Research and development expenses decreased to $10.7 million in Q2 2025 from $23.7 million in Q2 2024, attributed to reduced clinical expenses related to the PIVOT-PO trial [17][20]. - General and administrative expenses increased slightly to $5.9 million in Q2 2025 from $5.5 million in Q2 2024, mainly due to higher personnel and professional service costs [17][20]. Pipeline Update - Tebipenem HBr is being developed as an oral carbapenem antibiotic for treating cUTI, including pyelonephritis, with the potential to reduce hospital stays and improve patient outcomes [3][6]. - The PIVOT-PO trial was stopped early for efficacy, with plans to submit data to the FDA in the second half of 2025 [6][7]. - The oral development program for SPR720 in nontuberculous mycobacterium pulmonary disease (NTM-PD) was suspended following an interim analysis that did not meet its primary endpoint [8]. Corporate Update - Esther Rajavelu was appointed as President and CEO of Spero effective May 2, 2025, and continues to serve as Chief Financial Officer [8]. - As of June 30, 2025, Spero had cash and cash equivalents of $31.2 million, with projections to fund operations into 2028 [9][19].

Tebipenem HBr (cUTI) - Tebipenem HBr is in Phase 3 clinical trials for complicated urinary tract infections (cUTI)[3] - The Phase 3 trial met its primary endpoint following a pre-specified interim analysis (IA) of data from 1,690 enrolled patients[18] - Approximately 2.9 million annual cUTI treatment episodes are attributed to $6+ billion in US healthcare costs[16] - Spero granted GSK an exclusive license for Tebipenem HBr (ex-Asia) and received $66 million upfront and $9 million in common stock investment[32] - Spero is eligible to receive up to $400 million in additional potential regulatory, commercial, and sales milestone payments, as well as royalties from GSK[32] - Spero qualified to receive $95 million in development milestones, with $23.75 million to be received in 2H 2025[33] SPR720 (NTM-PD) - The company has suspended its current development program for SPR720[6, 34] - An interim analysis of a Phase 2a oral study did not show sufficient separation from placebo, highlighting potential oral dose-limiting safety issues in subjects dosed at 1,000 mg orally once daily[37] Financial Foundation - Spero received $30 million upon SPA agreement with the FDA[33] - Spero to receive tiered low-single digit to low-double digit (if sales exceed $1 billion) tiered royalties on net product sales of Tebipenem HBr[33]