Antibiotics

Background/Objectives: This study aimed to describe the population pharmacokinetics of cefazolin (CFZ) using unbound serum and periprostatic adipose tissue concentrations and to optimize dosing regimens for patients undergoing robotic-assisted radical prostatectomy (RARP). Methods: We investigated the population pharmacokinetics of CFZ using 295 unbound serum and 67 periprostatic adipose tissue samples from 67 individuals. CFZ concentrations were determined in all samples. A nonlinear mixed-effects model was developed. The pharmacodynamic target was defined as maintaining unbound trough and periprostatic adipose tissue concentrations exceeding the minimum inhibitory concentration (MIC) against methicillin-susceptible Staphylococcus aureus (MSSA) for over 90% of the dosing interval (MIC₉₀; 0.5 mg/L). Results: Systemic clearance of unbound CFZ was significantly associated with creatinine clearance (CLcr). In patients with normal renal function, simulations showed that a 1 g CFZ infusion over 15 min maintained unbound concentrations exceeding the MSSA MIC₉₀ for >90% of the 3 h interval after the initial dose. Notably, in patients with mild renal impairment (CLcr ≤ 80 mL/min), a 5 h dosing interval also achieved a >90% probability of maintaining the target CFZ concentration. Conclusions: The simulations demonstrated that the probability of target attainment of >90% was maintained for up to 5 h in patients with mild renal impairment (CLcr ≤ 80 mL/min). These findings provide a pharmacokinetic rationale suggesting that the standard additional dose may not be necessary for this subgroup; however, future clinical studies are needed to validate safety and efficacy.

In the face of rising antimicrobial resistance, food insecurity, and climate change, bacteriophages are gaining renewed attention as promising biological alternatives to antibiotics across human, animal, and plant health sectors. Their high specificity, self-replicating capacity, and biodegradability make them valuable tools for combating antimicrobial or pesticide resistance and promoting sustainable biocontrol. This review discusses commonly accepted selection criteria for therapeutic phages, such as avoiding temperate types and screening for undesirable genes, while acknowledging ongoing debates and exceptions in specific clinical or ecological contexts. An overview of phage-based applications within a One Health framework is provided, spanning human medicine, veterinary practice, aquaculture, food safety and crop protection. Particular attention is given to agricultural biocontrol, where several successful plant protection strategies are highlighted, illustrating the feasibility and diversity of phage-based approaches. Despite their potential, key challenges remain regarding phage stability, formulation, and persistence under environmental conditions. Emerging innovations such as encapsulation, carrier bacteria, and protective formulations aim to enhance field performance. Furthermore, this review emphasizes the need to assess the environmental safety of phage applications, particularly their impacts on natural ecosystems, microbial communities, and ecological functions. Finally, the regulatory and policy challenges that currently limit the large-scale deployment of phages, particularly in the European Union, where they remain evaluated under conventional chemical pesticide frameworks are discussed. The development of dedicated regulatory pathways, better adapted to the specificities of phages, is argued to be essential for supporting their integration into agroecological transition strategies and next-generation antimicrobial policies.

Background: AMR is a public health concern which leads to high global morbidity and mortality. Immunocompromised patients, who are more susceptible to contracting potentially life-threatening infections, are faced with reduced treatment options due to emerging AMR. Ceftolozane/tazobactam is a novel β-lactam/β-lactamase inhibitor which displays effectiveness against resistant Gram-negative infections. Methods: SPECTRA was a multinational, observational study conducted in seven countries including 617 patients who received ≥48 h of ceftolozane/tazobactam. Medical-record data were collected up to 6 months before treatment and 30 days after the final dose or until death. This analysis describes clinical outcomes and healthcare resource use in patients with sepsis or who were immunocompromised, specifically in patients with hematologic malignancy with and without solid tumor, febrile neutropenia, and solid organ transplant patients. Results: Clinical success ranged from 50.0% in patients with hematologic malignancy and solid tumor to 69.4% in 38 patients with febrile neutropenia. All-cause in-hospital mortality was 23.1–42.9%, with the lowest rates in patients with solid organ transplant. ICU admission was 46.4–68.2% across subpopulations (excluding febrile neutropenia) with the lowest rates in patients with hematologic malignancy. ICU length of stay was lowest within transplant patients (9 days) and highest within the hematologic malignancy and solid tumor population (32 days). Conclusions: The results from this sub analysis of SPECTRA showed that ceftolozane/tazobactam was associated with clinical success in the selected immunocompromised and sepsis patient populations and may lead to reduced morbidity, mortality, and healthcare-resource use. Further research is required to standardize treatment protocols and improve patient outcomes.