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<h3>Background and Importance</h3> Dalbavancin is a long-acting lipoglycopeptide active against Gram-positive bacteria exhibiting rapid bactericidal activity. For difficult-to-treat infections, different dosing regimens have been proposed but limited comparative clinical pharmacokinetic (PK) data are available. Although with limited evidence, therapeutic drug monitoring (TDM) has been employed to extend dosing intervals while ensuring optimal drug exposure. <h3>Aim and Objectives</h3> To evaluate, in a pilot TDM study, whether dalbavancin maintains sufficient plasma concentrations (Cp) at different time points after administration, potentially allowing extended dosing intervals. <h3>Material and Methods</h3> Prospective PK study conducted in a tertiary hospital including all patients with dalbavancin TDM (November 2024–August 2025). Demographic, clinical, PK and microbiological data were collected. Blood samples were obtained at various time points post-administration: ≤1 week, 1–2 weeks, 2–3 weeks, and >3 weeks. A validated UPLD-MS/MS method was used. Preclinical data suggest that a PK/PD target Cp above 4–8 mg/L before the next dose is sufficient to ensure efficacy against staphylococci (MIC ≤0.125 mg/L). <h3>Results</h3> Twenty-two patients were included (50% women). Characteristics (median (range)): age 72 (28–95) years, Body Mass Index: 26.6(17.8–38.8) kg/m<sup>2</sup>, Charlson Index: 2 (0–6), baseline glomerular filtration rate: 80(31–119) mL/min, serum creatinine: 0.9(0.5–1.7) mg/dL. Infection sites: osteoarticular (72.7%) and endovascular (27.3%). Targeted therapy was used in 20 patients (90.9%), being polymicrobial infections in seven (31.8%). Main microorganisms were: coagulase-negative staphylococci in 12 (41.4%) patients, MRSA in seven (24.1%), <i>E. faecalis</i> in four (13.8%), and MSSA in three (10.3%). MIC data were available for eight isolates (36.4%), of which 87.5% showed MIC <0.125 mg/L (EUCAST clinical breakpoint). Eighteen (81,8%) patients received a single dose (table 1), while four received multiple doses (three on suppressive therapy). The three patients on suppressive regimens received: 500 mg/2 weeks, 1500 mg/2 weeks and 1500 mg monthly achieving Cp of 25, 51, and 28 mg/L, respectively, before next administration. The last patient received two 1500-mg doses one week apart, reaching a Cp of 55.8 mg/L measured two weeks after the second dose. <h3>Conclusion and Relevance</h3> In this pilot TDM study, dalbavancin Cp after single or multiple doses remained well above the established threshold (8 mg/L). These results support the potential for extending dosing intervals to optimise treatment outcomes, patient convenience, and healthcare costs. <h3>Conflict of Interest</h3> No conflict of interest