A Cost-Effectiveness Analysis of Axicabtagene Ciloleucel Versus Glofitamab in Third-Line Diffuse Large B-Cell Lymphoma Patients in the United States

• Published in: Transplantation and cellular therapy 2024-02, Vol.30 (2), p.S367-S368
• Main Authors: Locke, Frederick L., Hasegawa, Ken, Patel, Anik R., Hofmann, Sarahmaria, Kievit, Bradley, Blissett, Robert, Ray, Mark
• Format: Article
• Language: English
• ISSN: 2666-6367; 2666-6367
• DOI: 10.1016/j.jtct.2023.12.512

Several innovative immunotherapies have been introduced over recent years that have improved the outlook for relapsed and refractory (r/r) diffuse large B-cell lymphoma (DLBCL). Two classes of these new treatments include chimeric antigen receptor T-cell (CAR-T) and the T-cell engaging bispecific antibodies (BsAbs). Axicabtagene ciloleucel (axi-cel), a CAR-T, was first approved for treatment of r/r DLBCL in 2017 and has follow up data to 5 years demonstrating a durable response while glofitamab, a BsAb, received accelerated FDA approval in 2023 but survival data are immature. We developed a patient level microsimulation model to compare the cost effectiveness of axi-cel versus glofitamab in the third line (3L) DLBCL setting. A discrete event simulation framework was used to simulate lifetime health and economic outcomes after initiation of either axi-cel or glofitamab in 3L+ DLBCL patients. For both axi-cel and glofitamab, mixture cure models (MCM) were used in a naïve comparison to extrapolate 3L survival data from ZUMA-1 and NCT03075696 respectively. Considerable uncertainty surrounds the durability of glofitamab response. The base case MCM cure fraction (10%) was chosen such that the overall survival data predicted by the model best fit the overall survival data from NCT03075696. A scenario analysis using a standard parametric model for the glofitamab patients was explored. A United States (US) payer perspective was used. Treatment data and costs were sourced from the available literature and Micromedex and inflated to 2023 US prices. Costs and utilities were discounted at 3.0% annually. In the base case analysis, the axi-cel arm of the model had discounted costs of $508,508 compared to the glofitamab arm's $255,784. The cost of treating with glofitamab varied as some patients with fast progression had lower treatment costs while patients with longer response had 12 cycles of treatment at a high cost. Due to the higher projected survival and duration of progression-free disease in the axi-cel arm, the discounted quality-adjusted life year (QALYs) were also higher for axi-cel compared to glofitamab (4.62 versus 2.01). The incremental cost effectiveness ratio (ICER) for axi-cel versus glofitamab was $96,829 per QALY, indicating that axi-cel would be considered cost effective in the US payer setting. In a scenario analysis with no cure for glofitamab, the ICER for axi-cel decreased to $79,562 suggesting that the relative durability of treatment response is