A Cost-Effectiveness Analysis of Mosunetuzumab vs Tisagenlecleucel for Treatment of Third- or Higher-Line (3L+) Relapsed or Refractory (R/R) Follicular Lymphoma (FL) in Italy.

Purpose: To compare the cost-effectiveness of mosunetuzumab with tisagenlecleucel for treating patients with relapsed or refractory follicular lymphoma (R/R FL 3L+) from the perspective of the Italian National Health Service (NHS).

Patients and methods: The analysis employs a weekly cycle partitioned survival model (PSM) with a lifetime horizon. The PSM model tracks patient outcomes based on time-to-event data, including progression-free survival (PFS) and post-progression survival (PPS). A matching-adjusted indirect treatment comparison (MAIC) approach was used to account for differences in trial population characteristics on the relative efficacy of mosunetuzumab to tisagenlecleucel. PFS and overall survival (OS) were extrapolated beyond the trial period by applying the hazard ratios from the MAIC to mosunetuzumab's parametric survival curves. Utility values and patient data are retrieved from the GO29781 trial. Economic inputs, from the perspective of the Italian NHS, include direct medical costs such as drugs, administration, monitoring, adverse event (AE) management, therapy following FL progression. Discontinuation and terminal care costs were also considered. Probabilistic sensitivity (PSA) and scenario analyses were conducted.

Results: Mosunetuzumab was found to be dominant compared to tisagenlecleucel, resulting in an increase of 0.98 life years (LYs) and 0.70 quality-adjusted life years (QALYs), while also being associated with lower overall costs. The sensitivity analysis consistently favored mosunetuzumab, with 94% of simulations demonstrating its cost-effectiveness based on the Italian WTP threshold of €40,000/QALY. Even in a scenario where tisagenlecleucel maintained a PFS advantage with assumed equivalence in OS, mosunetuzumab still showed a favorable cost-saving profile due to its lower incremental costs.

Conclusion: In the Italian setting, mosunetuzumab is a cost-effective treatment option compared to tisagenlecleucel for adult patients with R/R 3L+ FL, presenting favourable outcomes from the perspective of the NHS. Future research and data collection efforts are crucial to validate these findings and reduce uncertainties regarding long-term clinical and economic implications.