BARDA Provides Further Support for Basilea’s Ceftibuten-Ledaborbactam Programme Targeting Complicated Urinary Tract Infections

BARDA Provides Further Support for Basilea’s Ceftibuten-Ledaborbactam Programme Targeting Complicated Urinary Tract Infections

(IN BRIEF) Basilea Pharmaceutica has received an additional USD 13.3 million from BARDA to continue development of ceftibuten-ledaborbactam etzadroxil, an investigational oral beta-lactam/beta-lactamase inhibitor antibiotic being developed for complicated urinary tract infections, including pyelonephritis. The latest tranche brings BARDA’s total committed funding to Basilea to USD 25 million, with the contract carrying the potential for up to USD 133 million in further non-dilutive funding. The funding will support continued development work, including preparation for a phase 3 clinical programme. Ceftibuten-ledaborbactam is being developed to target complicated urinary tract infections caused by multidrug-resistant Gram-negative bacteria, particularly Enterobacterales that express resistance enzymes such as ESBLs, cephalosporinases and carbapenemases. The candidate has received Qualified Infectious Disease Product and Fast Track designations from the U.S. FDA for complicated and uncomplicated urinary tract infections, but it remains investigational and is not approved for commercial use in any country.

(PRESS RELEASE) ALLSCHWIL, 28-May-2026 — /EuropaWire/ — Basilea Pharmaceutica Ltd, Allschwil, a commercial-stage biopharmaceutical company focused on addressing serious bacterial and fungal infections, has received an additional USD 13.3 million from the Biomedical Advanced Research and Development Authority to continue development of its investigational oral antibiotic ceftibuten-ledaborbactam etzadroxil.

BARDA is part of the Administration for Strategic Preparedness and Response within the U.S. Department of Health and Human Services. The new funding will support the continued advancement of ceftibuten-ledaborbactam etzadroxil, a beta-lactam/beta-lactamase inhibitor combination being developed for complicated urinary tract infections, including pyelonephritis.

Ceftibuten-ledaborbactam etzadroxil is designed to address infections caused by multidrug-resistant Gram-negative bacteria, an area where effective oral treatment options remain limited. The latest BARDA tranche brings the total amount committed to Basilea under the agreement to USD 25 million. The contract could provide up to an additional USD 133 million in non-dilutive funding, supporting further development activities for the antibiotic candidate.

David Veitch, Chief Executive Officer of Basilea, said the company is pleased to be advancing ceftibuten-ledaborbactam in collaboration with BARDA. He noted that the additional funding will help Basilea continue development work, including preparation for the clinical phase 3 programme. Veitch said the candidate has the potential to address an important unmet medical need by offering an oral treatment option for complicated urinary tract infections caused by multidrug-resistant Gram-negative pathogens.

Beta-lactam/beta-lactamase inhibitor combinations play an important role in treating infections caused by resistant bacteria. Many Gram-negative bacteria produce enzymes, including extended spectrum beta-lactamases, that can make commonly used antibiotics ineffective. Beta-lactamase inhibitors are intended to block these resistance enzymes, helping restore the activity of beta-lactam antibiotics against bacterial strains that would otherwise be resistant.

Ledaborbactam etzadroxil is the orally bioavailable prodrug of ledaborbactam, a novel broad-spectrum boronic acid beta-lactamase inhibitor. It is being developed in combination with ceftibuten, an oral cephalosporin antibiotic approved in the United States for upper and lower respiratory tract infections and approved outside the United States for urinary tract infections.

Preclinical studies have shown that ledaborbactam etzadroxil can restore the activity of ceftibuten against strains of Enterobacterales that express Ambler class A extended spectrum beta-lactamases, class C cephalosporinases, class A carbapenemases such as KPC, and class D carbapenemases such as OXA-48. Studies have also demonstrated activity against multidrug-resistant Enterobacterales.

Ceftibuten-ledaborbactam etzadroxil has received Qualified Infectious Disease Product and Fast Track designations from the U.S. Food and Drug Administration for complicated urinary tract infections and uncomplicated urinary tract infections. The antibiotic remains investigational and has not been approved for commercial use in any country.

Complicated urinary tract infections, including kidney infections such as pyelonephritis, are among the most common bacterial infections in both hospital and community settings. These infections arise when bacteria ascend from the bladder and are accompanied by local and systemic signs and symptoms. Growing bacterial resistance has reduced the availability of effective oral antibiotics for these infections, creating a need for new treatment options that can address resistant pathogens.

At present, there are no approved oral beta-lactam or beta-lactam/beta-lactamase inhibitor combinations effective against Enterobacterales expressing Ambler class A ESBLs, class C cephalosporinases, and class A and D serine carbapenemases, including KPC and OXA-48. Basilea’s development programme is intended to help address this treatment gap through a novel oral antibiotic approach.

About beta-lactam/beta-lactamase inhibitor (BL/BLI) combinations

Many Gram-negative bacteria express enzymes such as extended spectrum beta-lactamases (ESBL) that confer resistance against commonly used antibiotics. Beta-lactamase inhibitors block these enzymes and restore the activity of beta-lactam antibiotics against initially resistant Gram-negative bacteria, therefore BL/BLI combinations are an important addition to the armamentarium for the treatment of infections caused by multidrug-resistant bacterial pathogens.

About ceftibuten-ledaborbactam etzadroxil

Ledaborbactam etzadroxil is the orally bioavailable prodrug of ledaborbactam, a novel broad-spectrum boronic acid beta-lactamase inhibitor, which is being developed in combination with ceftibuten, an oral cephalosporin antibiotic, which is approved in the US for the treatment of upper and lower respiratory tract infections and for urinary tract infections outside the US. In vitro and in vivo studies demonstrated that ledaborbactam etzadroxil restores the activity of ceftibuten against strains of Enterobacterales expressing Ambler class A extended spectrum beta-lactamases (ESBLs), class C cephalosporinases, and class A and D carbapenemases (KPC and OXA-48, respectively) as well as multidrug-resistant (MDR) Enterobacterales.[2] Ceftibuten-ledaborbactam etzadroxil has been granted Qualified Infectious Disease Product (QIDP) and Fast Track designations by the US Food and Drug Administration (FDA) for cUTI and uncomplicated urinary tract infections. Ceftibuten-ledaborbactam etzadroxil is an investigational drug and is not yet approved in any country for commercial use.

About complicated urinary tract infections (cUTI)

Complicated UTIs, which include pyelonephritis (kidney infections), are defined as urinary tract infections ascending from the bladder accompanied by local and systemic signs and symptoms and are one of the most common bacterial infections in hospital and community settings. Increasing resistance of bacteria causing complicated urinary tract infections has led to limited availability of effective oral antibiotic treatment options.[3] Currently, there are no approved oral beta-lactam or beta-lactam/beta-lactamase inhibitor combinations that are effective against Enterobacterales expressing Ambler class A ESBLs, class C cephalosporinases, and class A & D serine carbapenemases (KPC and OXA-48).

About Basilea

Basilea is a commercial-stage biopharmaceutical company founded in 2000 and headquartered in Switzerland. We are committed to discovering, developing and commercializing innovative drugs to meet the needs of patients with severe bacterial and fungal infections. We have successfully launched two hospital brands, Cresemba for the treatment of invasive fungal infections and Zevtera for the treatment of bacterial infections. In addition, we have preclinical and clinical anti-infective assets in our portfolio. Basilea is listed on the SIX Swiss Exchange (SIX: BSLN). Please visit basilea.com.

Disclaimer

This communication expressly or implicitly contains certain forward-looking statements, such as “believe”, “assume”, “expect”, “forecast”, “project”, “may”, “could”, “might”, “will” or similar expressions concerning Basilea Pharmaceutica Ltd, Allschwil and its business, including with respect to the progress, timing and completion of research, development and clinical studies for product candidates. Such statements involve certain known and unknown risks, uncertainties and other factors, which could cause the actual results, financial condition, performance or achievements of Basilea Pharmaceutica Ltd, Allschwil to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements. Basilea Pharmaceutica Ltd, Allschwil is providing this communication as of this date and does not undertake to update any forward-looking statements contained herein as a result of new information, future events or otherwise.

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