Clinical Experience of Ceftaroline-Fosamil in Gram-Positive Infective Endocarditis: A Multicenter Real-World Observational Study

Background/Objectives: Ceftaroline fosamil (CFT) is a fifth-generation cephalosporin approved in Spain for skin and soft tissue infections and community-acquired pneumonia. CFT may also be useful against endovascular infections. This real-world study aimed to evaluate its effectiveness and safety in patients with Gram-positive (GP) infective endocarditis (IE). Methods: This observational, retrospective multicenter study enrolled adults with GP-IE treated with CFT for ≥48 h. Recruitment extended from CFT incorporation in participating hospitals through May 2024. Data were gathered on demographic, clinical, and microbiological variables, adverse effects, overall and IE-related mortality, relapses, and a composite unfavorable outcome. Results: Seventy-six patients (65.8% male) were enrolled, with a mean age of 68.9±12.8 yrs and age-adjusted Charlson index of 4; 55.3% had previous moderate/severe valvular heart disease, 35.5% had atrial fibrillation, 34.2% chronic heart failure, 17.1% chronic kidney disease, and 22.4% septic shock. IE was native valve-related in 53.9%, involving aortic valve in 38.2% and mitral in 30.3%. Staphylococcus aureus was isolated in 50.7%, being methicillin-resistant in 57.9% of cases. CFT was salvage therapy in 64.9% and combined with other antibiotics in 94.8%. Valve replacement was indicated in 63.6% but performed in only 34.7% of these. At six months, adverse effect rate was 9.2%, overall crude mortality 37.7%; infection-related mortality 28.9%, and composite unfavorable outcome 40.1%. In multivariate analysis, mortality-related factors were age-adjusted Charlson index, septic shock, and methicillin- sensitive S. aureus. Conclusions: CFT proved effective and safe for the real-life treatment of GP-related IE in clinically complex patients with high comorbidity and previous antibiotic therapy failures.