Transitioning from intravenous to subcutaneous ocrelizumab in a high-volume infusion center: A
Aurora Zanghì1, Paola Sofia Di Filippo1, Claudia Rutigliano1
1Department of Medical and Surgical Sciences, University of Foggia, Italy.
Background:
Subcutaneous (SC) ocrelizumab offers a streamlined alternative to intravenous (IV) infusion in the management of multiple sclerosis (MS). Building on time-and-motion (T&M) methodologies validated in oncology, we conducted a single-center operational study to quantify procedure-level time savings, estimate the resulting care-time dividend, and assess changes in patient flow following SC implementation.
Methods:
We employed a cross-sectional observational design in a five-chair day hospital treating ∼600 patients with MS treated with infusive therapies. T&M data were collected for 15 IV ocrelizumab administrations (April 2025) and 15 SC administrations (November 2025), capturing active clinical time across four phases: premedication, administration, observation, and checkout. Service-flow metrics (monthly visit volume, mean waiting time) were extracted from the electronic queue system for May 2025 (early SC implementation) and November 2025 (mature SC adoption). A deterministic operational model projected capacity gains under different SC adoption scenarios.
Results:
SC ocrelizumab reduced total active clinical time from 320 to 60 min (-81%), driven by administration (210→10 min) and observation (60→15 min) reductions. At 15 SC administrations/month, this translated into 65 clinical hours and 50 chair-hours released-equivalent to 14 IV-equivalent infusion slots. Despite unchanged ocrelizumab volumes, monthly visits increased (+7.9%) and mean waiting time decreased (-30%) from May to November 2025. Scenario modeling projected 100-133 chair-hours released at 30-40 SC administrations/month.
Conclusions:
Transitioning from IV to SC ocrelizumab yields substantial procedural efficiencies and frees infusion-unit capacity. The care-time dividend enables expanded access to complex therapies without additional staff or infrastructure, positioning SC ocrelizumab as a structural efficiency tool in MS care.
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