The U.S. Food and Drug Administration has approved GSK and Spero Therapeutics’ tebipenem pivoxil for the treatment of complicated urinary tract infections, according to a June 18 announcement. The drug, which will be marketed under the brand name Utebzi, is expected to be available in the United States by the end of the year.
GSK said that more than 3 million cases of complicated urinary tract infections (cUTIs) are recorded annually in the U.S., with treatments failing in over a third of patients due to drug-resistant pathogens. Carbapenem antibiotics are often used as a last line of defense against these resistant infections but have previously only been available intravenously.
Utebzi is now the first oral carbapenem option for patients whose cUTI is caused by susceptible pathogens and who have limited or no alternative treatment options, GSK said. The drug was originally developed by Spero Therapeutics but was rejected by the FDA in June 2022 after regulators found that its Phase 3 study did not sufficiently support approval. The agency requested an additional study to establish efficacy.
In December 2022, GSK paid $66 million upfront and committed up to $750 million in milestones for exclusive rights to develop and commercialize tebipenem pivoxil globally except in Japan and certain Asian territories. GSK and Spero resubmitted their application for Utebzi in December 2025.
The FDA’s approval was supported by data from the Phase 3 PIVOT-PO study, which showed that Utebzi was non-inferior to intravenous imipenem-cilastatin. Patients receiving Utebzi had a treatment success rate of 58.5%, compared with 60.2% among those on intravenous therapy. An independent data board recommended stopping PIVOT-PO early due to efficacy results announced in May 2025.
With this latest clearance, GSK has achieved three infectious disease approvals within eighteen months. In March 2025, it received FDA approval for Blujepa as an oral antibiotic for uncomplicated urinary tract infections in female patients aged twelve years and older; later that year, Blujepa also gained regulatory clearance as a new class of antibiotics for uncomplicated urogenital gonorrhea—the first such advance in over thirty years.
