Cost-effectiveness of axicabtagene ciloleucel versus tisagenlecleucel for the treatment of 3L + relapsed/refractory large B-cell lymphoma in the United States: incorporating longer survival results.

Aims: To provide an update on the cost-effectiveness of the chimeric antigen receptor (CAR) T-cell therapies axicabtagene ciloleucel (axi-cel) and tisagenlecleucel (tisa-cel) for the treatment of relapsed/refractory (r/r) large B-cell lymphoma (LBCL) among patients who have previously received ≥2 lines of systemic therapy using more mature clinical trial data cuts (60 months for axi-cel overall survival [OS] and 45 months for tisa-cel OS and progression-free survival [PFS]).

Methods: A partitioned survival model consisting of three health states (pre-progression, post-progression and death) was used to estimate quality-adjusted life years (QALYs) and costs associated with axi-cel and tisa-cel over a lifetime horizon. PFS and OS inputs for axi-cel and tisa-cel were based on a previously published matching-adjusted indirect treatment comparison (MAIC). Long-term OS and PFS were extrapolated using parametric survival mixture cure models (PS-MCMs). Costs of CAR-T cell therapy drug acquisition and administration, conditioning chemotherapy, apheresis, CAR T-specific monitoring, stem cell transplant, hospitalization, adverse events, routine care, and terminal care were sourced from US cost databases. Health state utilities were derived from previous publications. Model inputs were varied using a range of sensitivity and scenario analyses.

Results: Compared with tisa-cel, axi-cel resulted in 2.51 additional QALYs and $50,185 additional costs (an incremental cost-effectiveness ratio [ICER] of $19,994 per QALY gained). In probabilistic sensitivity analysis (PSA), the ICER for axi-cel versus tisa-cel was ≤$50,000/QALY in 99.4% of simulations and ≤$33,500 in 99% of simulations. Axi-cel remained cost-effective versus tisa-cel (assuming a willingness-to-pay threshold of $150,000 per QALY) across a range of scenarios.

Conclusions: With longer-term survival data, axi-cel continues to represent a cost-effective option versus tisa-cel for treatment of r/r LBCL among patients who have previously received ≥2 lines of systemic therapy, from a US payer perspective.