Is Polatuzumab Vedotin Plus Bendamustine-Rituximab Cost-Effective For Patients In The United States With Transplant-Ineligible Relapsed/Refractory Diffuse Large B-Cell Lymphoma?

Polatuzumab vedotin (pola) plus bendamustine-rituximab (BR) demonstrated clinically meaningful improvements in response rates, PFS and OS, versus BR in transplant-ineligible relapsed/refractory diffuse large B-cell lymphoma (R/R DLBCL) (Sehn, Blood 2018). Pola+BR was FDA approved (June 2019) in R/R DLBCL (third-line treatment and beyond). We assessed the cost effectiveness of pola+BR in R/R DLBCL using GO29365 study data. In a randomised phase II trial (GO29365/NCT02257567) patients with R/R DLBCL received pola+BR (n=40) or BR (n=40). A partitioned survival model was developed utilising OS and investigator-assessed PFS data. Drug utilisation, treatment duration, and adverse events (AEs) were based on trial data. Costs included drug acquisition/administration, AEs, PFS routine care, progressive disease (PD) medical care and end-of-life care. QALYs were calculated using published utility estimates (Tisagenlecleucel NICE Report). The base-case analysis assumed OS was informed by PFS (extrapolated) and used a mixture cure rate model to estimate the proportion of putative long-term survivors (pola+BR: 21%; BR: 0% [Sehn, ICML 2019]). Scenario analyses: mixture cure rate based on OS only and standard parametric survival models. The total cost of pola+BR ($232,358) was $113,484 higher than BR ($118,874), primarily due to higher drug/administration costs ($170,028 vs $50,163, respectively). Pola+BR had cost-savings for PD (-$11,914) and end-of-life care (-$2,131) vs BR. AE costs were higher for pola+BR ($21,989) than BR ($15,505). Patients treated with pola+BR had increased QALYs vs BR (incremental: 2.49). The incremental cost-effectiveness ratio (ICER) was $45,535/QALY gained. Probabilistic sensitivity analyses showed pola+BR was cost effective versus BR in 52% and 94% of cases at a willingness-to-pay threshold of $50,000 and $100,000, respectively. Scenario analyses: ICER $46,186/QALY (OS only) and $115,751/QALY (parametric). Driven predominantly by higher PFS/OS and the higher estimated proportion of long-term survivors, the results suggest that pola+BR vs BR is cost effective for transplant-ineligible R/R DLBCL in the USA.