ANTIBIOTIC duration in patients with left-sided infective endocarditis was significantly reduced without compromising safety in the POET-II trial, according to findings presented during the European Society of Cardiology (ESC) Congress 2026.
The study evaluated whether antibiotic treatment length could be individualised based on patients’ clinical response, challenging the long-standing practice of administering therapy for up to 6 weeks.
Infective endocarditis is a potentially fatal condition involving infection of the heart’s inner lining, typically occurring alongside bloodstream infection. Current treatment strategies generally rely on prolonged courses of high-dose antibiotics.
Researchers sought to determine whether patients demonstrating a favourable early response could safely receive a shorter duration of therapy.
The open-label POET-II trial enrolled 508 clinically stable patients with left-sided infective endocarditis across 13 centres in Denmark, Sweden, and the United States.
Eligible participants had infection caused by Staphylococcus aureus, Enterococcus faecalis, or streptococci and were randomly assigned to either tailored therapy or standard treatment.
Patients in the tailored therapy group received a minimum of 2 to 4 weeks of antibiotic treatment, after which therapy was discontinued if predefined stabilisation criteria had been met.
The study population had a mean age of 70 years, and 75% were men.
The tailored approach reduced treatment duration by approximately one-third. Median antibiotic duration was 26 days in the tailored therapy group compared with 41 days in the standard therapy group, representing a significant difference of 15 days.
The primary endpoint, defined as median days alive without antibiotic treatment within 6 months after randomisation, favoured tailored therapy (183 days versus 169 days in the standard therapy group).
Safety outcomes remained comparable between groups. The composite endpoint of all-cause mortality, unplanned heart valve surgery, or symptomatic embolic events within 6 months occurred in 8.2% of patients receiving tailored therapy and 10.7% of those receiving standard treatment, meeting noninferiority criteria.
Although primary relapse rates were higher with tailored therapy, they remained low overall (5.1% versus 1.6% in the standard treatment group).
Researchers noted that most relapses were successfully managed by restarting antibiotic treatment.
The researchers concluded that a substantial proportion of patients with left-sided infective endocarditis could be eligible for reduced duration therapy, potentially offering benefits related to adverse effects, healthcare costs, microbial resistance, and patient quality of life.
Bundgaard H et al.; POET II Investigators. Response-tailored or standard-duration antibiotic treatment for infective endocarditis. N Engl J Med. 2026;DOI:10.1056/NEJMoa2607887.
Featured image: Saiful52 on Adobe Stock
Each article is made available under the terms of the Creative Commons Attribution-Non Commercial 4.0 License.
