Operationalizing Step-Up Dosing in Outpatient and Inpatient/Outpatient Hybrid Setting

The implementation of bispecific antibody step-up dosing has evolved from mandatory inpatient management to predominantly outpatient or hybrid approaches as clinical experience has grown. Most centers initially required hospitalization for all step-up doses but have transitioned to outpatient management for appropriate patients using prophylactic tocilizumab and dexamethasone to minimize cytokine release syndrome (CRS) risk. Hybrid models involve administering the first dose as an inpatient with early tocilizumab intervention, then completing subsequent step-up doses on an outpatient basis once the risk period has passed.

Patient selection for outpatient step-up dosing requires careful assessment of multiple factors including caregiver support availability, distance from the treatment center, tumor burden, and overall medical stability. Patients must be able to return quickly if complications arise, typically within 1 hour of the treatment facility, and should have reliable caregivers who can monitor for symptoms and assist with medication administration. Those with rapidly progressive disease, bulky tumor burden, or significant comorbidities may still benefit from inpatient monitoring during initial dosing phases.

The development of standardized protocols and staff education has been crucial for successful outpatient implementation. Clear algorithms for managing fever and CRS symptoms, readily available medications like tocilizumab in infusion centers, and coordination with emergency departments ensure appropriate response to complications. Community practices beginning bispecific programs may benefit from starting with inpatient step-up dosing to build experience and comfort before transitioning to outpatient models, with approximately two-thirds of selected patients successfully completing outpatient step-up when appropriate protocols are followed.