Institutional and national budget impact of alternative pembrolizumab dosing in non-small cell lung cancer: a real-world pharmacoeconomic analysis.

BACKGROUND: Pembrolizumab is among the costliest anticancer therapies; fixed dosing may cause drug wastage, particularly in lower-weight patients, adding to health-system budgetary pressure. RESEARCH DESIGN AND METHODS: This retrospective, single-center pharmacoeconomic analysis compared standard flat-dose pembrolizumab (200 mg every three weeks [Q3W] or 400 mg every six weeks [Q6W]) with a simulated weight-banded strategy (<65 kg, 65-90 kg, ≥90 kg) in adults with advanced non-oncogene-addicted non-small cell lung cancer treated at the Clinical Hospital Centre Rijeka, Croatia, during 2024. Institutional and national public-payer budget impact was modeled using list drug-acquisition prices, with one-way and probabilistic sensitivity analyses. RESULTS: Ninety-six patients received pembrolizumab during the study period. Weight-banded dosing reduced institutional drug consumption by 25%, yielding annual savings exceeding €1.1 million. National extrapolation, assuming Rijeka accounts for 10-30% of national pembrolizumab use, projected savings of €3.7-11.2 million annually. CONCLUSIONS: Weight-banded pembrolizumab dosing may reduce drug expenditure without evidence of compromised outcomes in this economic model; prospective clinical validation and consideration of pharmacodynamic, safety, and regulatory implications are warranted before implementation.