Cost-Effectiveness and Cost-Utility Analyses of Polatuzumab Vedotin With Rituximab and Chemotherapy vs Rituximab and Chemotherapy in Treating Naïve Diffuse Large B-Cell Lymphoma in Italy

OBJECTIVES: To assess the incremental cost-effectiveness (ICER) and cost-utility (ICUR) ratio of polatuzumab vedotin with rituximab and chemotherapy (Pola-R-CHP) versus rituximab and chemotherapy (R-CHOP) for treatment-naïve adult patients with diffuse large B-cell lymphoma (DLBCL), from the Italian Health Service perspective.

METHODS: A partitioned survival model of three mutually exclusive health-states –progression-free, progressed disease and death– was developed to estimate lifetime clinical outcomes and costs of patients treated with Pola-R-CHP or R-CHOP. Disease evolution was simulated through a mixture cure rate model (MCM), a statistical method able to support the evidence that a proportion of treated patients –75% for Pola-R-CHP and 64% for R-CHOP, both estimated from progression-free survival (PFS) Kaplain-Meier (KM) curves from the POLARIX trial with generalised gamma distribution– enters long-term remission. PFS R-CHOP curve extrapolated with MCM generalised gamma distribution was validated using the PFS KM curve from GOYA trial after adjusting with propensity score weighting. Health utilities from the GOYA trial were used to estimate QALYs. Direct healthcare costs, including drugs, administration, disease monitoring, adverse event management and post-progression therapy were collected from official and published Italian sources. Net prices for drugs with confidential rebates were used. Costs, reported in Euro-2022, and health gains were discounted at an annual 3% rate. Probabilistic sensitivity analysis (PSA) evaluated the uncertainties on input parameters.

RESULTS: Pola-R-CHP generated 0.52 additional LYs and 0.54 additional QALYs at an additional cost of €18,300 relative to R-CHOP. ICER for the comparison of Pola-R-CHP versus R-CHOP is around €35,000 per LY gained and ICUR is about €34,000 per QALY gained. PSA confirms the robustness of the model, with a high probability of dropping on the cost-effectiveness region.

CONCLUSIONS: In light of the unmet medical need, Pola-R-CHP should be considered a cost-effective option for treatment-naïve patients with DLBCL, since the deterministic incremental ratios are both below the threshold of €40,000.