Cost-Effectiveness Analysis of Frontline Treatment with Polatuzumab Vedotin in Diffuse Large B-Cell Lymphoma

Introduction: The POLARIX trial (NCT03274492) recently demonstrated that substituting polatuzumab vedotin (pola), a CD79b-targeted antibody-drug conjugate, for vincristine in standard R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone) chemoimmunotherapy for first-line therapy can prolong progression-free survival in patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL). However, the medication cost of pola-R-CHP (pola, rituximab, cyclophosphamide, doxorubicin, and prednisolone) regimen is substantially higher than that of R-CHOP treatment. It remains unknown whether the lower rate of treatment failure with pola-R-CHP can be translated into reduced subsequent healthcare costs, increased life years (LYs), and improved quality of life, which may offset the higher medication cost. This study aimed to investigate the cost-effectiveness of substituting pola for vincristine in first-line therapy for patients with newly diagnosed DLBCL from a US payer perspective.

Methods: We developed a decision analytic model to project lifetime quality-adjusted life years (QALYs) gained, LYs gained, and direct healthcare costs in newly diagnosed DLBCL patients. The model utilized a hypothetical cohort of patients at 65 years (the median age of disease onset). Direct healthcare costs were adjusted to 2021 US dollars, and an annual rate of 3% was used to discount future costs and benefits. Incremental cost-effectiveness ratios (ICERs) were calculated, and a willingness-to-pay (WTP) threshold of USD 150,000 per QALY gained was used as the acceptable level for determining cost-effectiveness. Sensitivity analyses and scenario analyses were conducted to assess the uncertainty of the base-case scenario and input parameters.

Results: Pola-R-CHP, compared to standard R-CHOP, was associated with an incremental cost of USD 90,439, an improvement of 0.89 QALYs and 1.14 LYs, leading to an ICER of USD 101,510/QALY. The model was most sensitive to the survival benefit provided by pola-R-CHP, the age of the patients at initial treatment, and the price of pola. The ICER would increase significantly if pola-R-CHP is ineffective in providing long-term remissions. Furthermore, the ICER value increased as patients were older at the beginning of the treatment. When patients were older than 76.5 years at initial treatment, the ICER would exceed the WTP threshold of USD 150,000/QALY. To make the pola-R-CHP regimen cost-effective in all age groups (up to 80 years old), the current price of pola, which was estimated to be USD 19,307 for 170 mg per treatment cycle, needed to be reduced by 20%. In the probabilistic sensitivity analysis, 48% and 73% of the iterations produced ICERs below WTP thresholds of USD 100,000/ QALY and USD 150,000/ QALY, respectively.

Conclusion: Our study findings suggest that pola-R-CHP, compared to the standard R-CHOP regimen, could be a cost-effective strategy in treatment-naïve DLBCL patients aged 65 years from a US payer perspective. However, several noticeable factors that could affect the cost-effectiveness profile of pola-R-CHP therapy should be considered in decision-making. The follow-up period of the POLARIX trial was relatively short, and mature survival data would be required to fully evaluate the value of pola in the treatment of newly diagnosed DLBCL.

Chou:aether AI: Other: The AI product in this abstract... investigators of this study w/commercial profit; National Taiwan University Hospital: Other: The AI product in this abstract... investigators of this study w/commercial profit.