Day-hospital long-acting antibiotic pathways show strong real-world clinical success, though the economic case remains modelled rather than proven

A retrospective, multicentre observational study across nine Italian centres evaluated real-world outcomes for 160 adult patients treated with long-acting lipoglycopeptides (dalbavancin and/or oritavancin) in a day-hospital setting between January 2020 and December 2025 Primary Study. Just over half of patients (54.4%) received these agents for off-label indications, principally osteomyelitis, prosthetic joint infection and spondylodiscitis, rather than the licensed indication of acute bacterial skin and skin-structure infection. Overall clinical success was 86.8% (138 of 159 patients with available outcome data), with no significant difference between in-label and off-label use, and the adverse-event rate was low (3.3%), with no treatment discontinuations attributable to adverse events.

The study also modelled cost impact from avoided inpatient bed-days: estimated net savings ranged from approximate cost-neutrality under conservative assumptions to a substantial figure under maximum assumptions, with sensitivity analysis showing a possible net loss at low inpatient daily-cost values.

The authors are explicit that this is an uncontrolled retrospective cohort with no matched inpatient or conventional-OPAT comparator, and describe their own findings as hypothesis-generating: the study cannot establish comparative efficacy, superiority, or actual cost savings against alternative pathways, only that outcomes and safety within this cohort were favourable.

For OPAT services considering single-visit, long-acting-agent pathways to reduce contact burden — particularly for patients facing travel or attendance barriers — this is real-world evidence of clinical feasibility and safety at meaningful scale, but the pharmacoeconomic case would need local costing against actual bed-day and OPAT nurse-visit costs before use in a business case, exactly as the authors themselves caution.