Initiation of Bispecific Antibodies Associated With High Care Costs for Patients With MM

Key Takeaways

• Among Medicare patients with multiple myeloma (MM) who initiated treatment with bispecific antibodies in inpatient settings, total care costs averaged to $36 964 per patient.
• Patients with longer lengths of stay or adverse events (AEs) accumulated higher costs than those with shorter hospitalizations or no AEs.
• Outpatient settings could potentially reduce costs and improve disease management among patients with MM.

Step-up dosing is common for patients with MM initiating treatment with bispecific antibodies, especially in inpatient settings.

To evaluate the economic burden of bispecific antibodies, researchers compared care costs for 1129 Medicare patients being treated in inpatient settings at hospitals not exempt from the Prospective Payment System (PPS).

The Economic Burden of Bispecific Antibodies

The estimated average cost per day of hospitalization was $3963, with total costs averaging to $36 964 per patient for inpatient step-up dosing.

Mean Medicare payments were $28 366 per patient. Actual payments exceeded cost estimates by $2764 to $8149 for length of stays of 1 to 4 days.

For patients with a length of stay of 6 to 9 days, payments were $6735 lower than estimated costs. Patients who were hospitalized for 10 days or more made payments lower than care costs by $16 659, suggesting a net loss.

Patients with infection, neutropenia, and febrile neutropenia had higher inpatient net losses than patients without AEs.

After bispecific antibody initiation, 74% of patients received follow-up doses in an outpatient setting. The average cumulative longitudinal payments were greater than the cumulative costs within 2 to 3 months.

Implications for Oncology Care

These findings illustrate a substantial financial burden for inpatient settings administering step-up dosing for patients with MM, especially among patients with longer hospital stays.

The authors said, “Care models (e.g. [outpatient step-up dosing]) are key to manage initiation costs and ensure delivery of care for [bispecific antibodies] remains financially sustainable.”

Understanding the costs associated with inpatient step-up dosing may help stakeholders anticipate the financial implications of bispecific antibody treatment in MM.

Reference

Joseph N, Inocencio T, Heitkamp S, et al. Net costs associated with inpatient (IP) administration of step-up dosing (SUD) of bispecific antibodies (bsAbs) among Medicare patients (pts) with relapsed/refractory multiple myeloma (MM). J Clin Oncol. 2026;44(16):e19504. doi:10.1200/JCO.2026.44.16_suppl.e19504