Inpatient administration of bispecific antibody step-up dosing associated with financial burden

Non-prospective payment system (PPS)-exempt hospitals administering inpatient step-up dosing for bispecific antibodies saw a “large financial” burden, according to a study. This suggests that care models, such as outpatient step-up dosing, “are key to managing bispecific antibody initiation costs and ensuring financially sustainable delivery of care,” according to Nisha Joseph, MD, of the Winship Cancer Institute at Emory University in Atlanta, and colleagues who presented the study at the 2026 SOHO Annual Meeting.

The researchers compared net costs and payments for bispecific antibody inpatient initiation for Medicare patients (aged ≥65 years) at non-PPS-exempt hospitals.

Using Medicare fee-for-service Part A/B claims from October 25, 2021, to October 20, 2024, hospital costs were estimated by application of center-specific Medicare cost-charge ratios from Centers for Medicare & Medicaid Services Hospital Cost Reports to inpatient-facility charges.

The study assessed 1129 patients with relapsed or refractory multiple myeloma who initiated a bispecific antibody and had a mean length of stay of nine days. The estimated cost per inpatient step-up dosing stay was $36,964, or $3963 per day.

Mean Medicare payments were $28,366, with a mean loss per patient of $8598. On average, payments exceeded estimated costs by $2764 to $8149 for one- to four-day hospitalizations. For those with lengths of stay of six to nine days and ≥10 days, payments were lower than costs by $6735 and $16,659, respectively, which the authors said suggests a loss.

For subsequent outpatient administrations that were required by 74% of patients, mean cumulative longitudinal payments exceeded cumulative costs within two to three months. Inpatient stay net losses increased with cases of:

• Infection (−$6406)
• Neutropenia (−$7006)
• Febrile neutropenia (−$10,018)

This abstract was accepted and previously presented at the 2026 ASCO Annual Meeting. 

Reference

Joseph N, Inocencio T, Heitkamp S, et al. Net costs associated with inpatient administration of step-up dosing of bispecific antibodies among Medicare patients with relapsed/refractory multiple myeloma. Abstract MM-768. Presented at the 2026 Society of Hematologic Oncology Annual Meeting; September 9-12, 2026; Houston.

Read more from SOHO 2026 here.