Introduction of Glofitamab for the Treatment of Relapsed or Refractory Diffuse Large B-Cell Lymphoma (DLBCL) after ≥2 Lines of Systemic Therapy Results in Cost Savings to the Healthcare System Based on a United States Budget Impact Analysis

Background: Glofitamab is a humanized CD20xCD3 T-cell engaging bispecific immunoglobulin G1 antibody that was granted accelerated approval from the United States (US) Food and Drug Administration for adult patients with relapsed or refractory (R/R) DLBCL, not otherwise specified or large B-cell lymphoma arising from follicular lymphoma, after ≥2 lines of systemic therapy. We conducted a budget impact analysis to assess the effect of introducing glofitamab as a treatment option for R/R DLBCL after ≥2 lines of systemic therapy by estimating total costs to a US health plan, with and without glofitamab.

Methods: A 3-year budget impact model was developed for a hypothetical cohort of 1 million patients enrolled in a mixed commercial/Medicare health plan. Comparators were axicabtagene ciloleucel (Axi-cel), lisocabtagene maraleucel (Liso-cel), tisagenlecleucel (Tisa-cel), loncastuximab tesirine (Lonca), polatuzumab vedotin + bendamustine + rituximab (Pola-BR), rituximab + gemcitabine + oxaliplatin (R-GemOx), tafasitamab + lenalidomide, and epcoritamab. Total costs included those of the drug (based on mean treatment duration observed in pivotal trials) and its administration, as well as those arising from managing adverse reactions (including cytokine release syndrome and hematology laboratory abnormalities) and routine care. Drug costs were estimated based on the average wholesale acquisition cost reported in AnalySource ® (2023) or the Average Sales Price in the Centers for Medicare Services Pricing File (2023). All other costs were based on several US published sources. Market shares were based on Genentech internal projections and expert opinions. All costs were inflated to 2023 US dollars, where applicable. Budget impact outcomes over 3 years were presented as total cumulative costs and average per-member per-month (PMPM) costs. In a scenario analysis, we examined the budget impact when maximum treatment duration per US prescribing information (USPI) was applied across treatments. The net budget impact was the difference in costs between the projected scenario with glofitamab and the current scenario without glofitamab.

Results: Among 1 million patients,approximately nine patients were projected to be eligible for treatment of R/R DLBCL after ≥2 lines of therapy.The introduction of glofitamab as a treatment option resulted in an estimated cumulative total cost saving of $728,697 over 3 years; the average PMPM net budget impact was −$0.0202 ( Figure A). The introduction of glofitamab reduced costs across all categories ( Figure A). Among the newer therapies including chimeric antigen receptor T-cell therapy and bispecific antipbodies, the total cost per treated patient was lowest for glofitamab over the 3-year period: glofitamab = $226,658; Tisa-cel = $564,113; Axi-cel = $540,002; Liso-cel = $516,272; epcoritamab = $335,293 ( Figure B). In the scenario analysis where the full treatment duration per USPI was modeled, the introduction of glofitamab as a treatment option resulted in greater cost savings over 3 years, versus the current scenario without glofitamab (cumulative:

−$921,407 and PMPM: −$0.0256).

Conclusions: Over 3 years, the estimated cumulative per-patient cost of glofitamab is projected to be the lowest when compared with per-patient costs of other available T-cell engaging therapies, resulting in cost savings after its formulary adoption for the treatment of R/R DLBCL after ≥2 lines of therapy.