Spero Therapeutics and GSK Unveil Positive Phase 3 Results for Tebipenem HBr

Spero Therapeutics, Inc. and GSK plc have announced promising results from the pivotal Phase 3 PIVOT-PO trial that evaluated the efficacy and safety of tebipenem HBr, a potential oral treatment for complicated urinary tract infections (cUTIs), including pyelonephritis. The findings were presented on October 20, 2025, during a late-breaking oral abstract session at IDWeek 2025 in Atlanta, Georgia.

This trial marks a significant milestone in the development of tebipenem HBr, as it could become the first oral carbapenem antibiotic available for patients. Carbapenems are a class of antibiotics typically administered intravenously and are crucial for treating serious bacterial infections. The ability to offer an oral formulation could greatly enhance patient compliance and accessibility to treatment.

The PIVOT-PO study included a robust patient population, and the data demonstrated that tebipenem HBr effectively met its primary endpoint, showcasing superior efficacy compared to the current standard of care. The analysis revealed a statistically significant reduction in the clinical failure rate, indicating that tebipenem HBr could provide a new option for patients suffering from cUTIs.

Safety assessments indicated that tebipenem HBr was well-tolerated, with an adverse event profile consistent with other antibiotics in the same category. These results suggest that tebipenem HBr may not only be effective but also safe for use in a broader patient population.

Dr. Ankit Mahadevia, Chief Executive Officer of Spero Therapeutics, expressed optimism about the trial’s results. He stated, “We are excited to see the positive outcomes from the PIVOT-PO trial, as tebipenem HBr has the potential to address a significant unmet need in the treatment of complicated urinary tract infections.”

The collaboration between Spero Therapeutics and GSK is part of a strategic effort to advance innovative therapies in the field of infectious diseases. Both companies are committed to addressing the growing concern of antibiotic resistance, which has made the development of new treatments increasingly vital.

As the results gain attention within the medical community, the next steps include preparing regulatory submissions to seek approval for tebipenem HBr. This will involve compiling comprehensive data from the trial and engaging with health authorities to demonstrate the drug’s clinical benefits.

With the increasing prevalence of antibiotic-resistant infections, the introduction of an oral carbapenem antibiotic could provide a much-needed alternative for healthcare professionals and patients alike. The implications of this development extend beyond individual patients, potentially impacting healthcare systems by reducing hospital stays and improving overall treatment outcomes.

The presentation at IDWeek 2025 not only highlighted the findings of the PIVOT-PO trial but also opened discussions on the future of antibiotic therapies in an era where resistance poses a significant challenge. The response from healthcare professionals and researchers during the session underscored the importance of ongoing innovation in this critical area of medicine.

In conclusion, Spero Therapeutics and GSK’s announcement represents a promising advancement in the treatment landscape for complicated urinary tract infections. As further evaluations and regulatory processes unfold, tebipenem HBr may soon become a vital tool in combating bacterial infections effectively.