Budget Impact of Introducing Fixed-Duration Mosunetuzumab for the Treatment of Relapsed or Refractory Follicular Lymphoma After Two or More Lines of Systemic Therapy in the USA.

OBJECTIVE: This study aimed to assess the budget impact of introducing fixed-duration mosunetuzumab as a treatment option for adult patients with relapsed or refractory follicular lymphoma after at least two prior systemic therapies and to estimate the total cumulative costs per patient in the USA. METHODS: A 3-year budget impact model was developed for a hypothetical 1-million-member cohort enrolled in a mixed commercial/Medicare health plan. Comparators were: axicabtagene ciloleucel, tisagenlecleucel, tazemetostat, rituximab plus lenalidomide, copanlisib, and older therapies (rituximab or obinutuzumab ± chemotherapy). Costs per patient comprised treatment-associated costs including the drug, its administration, adverse events, and routine care. Dosing and safety data were ascertained from respective package inserts and clinical trial data. Drug costs (March 2023) were estimated based on the average wholesale acquisition cost reported in AnalySource®, and all other costs were based on published sources and inflated to 2022 US dollars. Market shares were obtained from Genentech internal projections and expert opinion. Budget impact outcomes were presented on a per-member per-month basis. RESULTS: Compared with a scenario without mosunetuzumab, its introduction over 3 years resulted in a budget increase of $69,812 (1% increase) and an average per-member per-month budget impact of $0.0019. Among the newer therapies, mosunetuzumab had the second-lowest cumulative per patient cost (mosunetuzumab = $202,039; axicabtagene ciloleucel = $505,845; tisagenlecleucel = $476,293; rituximab plus lenalidomide = $263,520; tazemetostat = $250,665; copanlisib = $127,293) and drug costs, and its introduction only increased total drug costs by 0.1%. By year 3, the cumulative difference in the per patient cost with mosunetuzumab was -$303,805 versus axicabtagene ciloleucel, -$274,254 versus tisagenlecleucel, -$61,481 versus rituximab plus lenalidomide, -$48,625 versus tazemetostat, and $74,747 versus copanlisib. Older therapies were less costly with 3-year cumulative costs that ranged from $36,512 to $147,885. CONCLUSIONS: Over 3 years, the estimated cumulative per patient cost of mosunetuzumab is lower than most available newer therapies, resulting in a small increase in the budget after its formulary adoption for the treatment of relapsed or refractory follicular lymphoma.

Cost-effectiveness analysis of mosunetuzumab for treatment of relapsed or refractory follicular lymphoma after two or more lines of systemic therapy in the United States.

AIMS: Mosunetuzumab has received accelerated approval by the US Food and Drug Administration for adult patients with relapsed or refractory (R/R) follicular lymphoma (FL) after two or more lines of systemic therapy. We evaluated the cost-effectiveness of mosunetuzumab for the treatment of R/R FL from a US private payer perspective. MATERIALS AND METHODS: A partitioned survival model simulated lifetime costs and outcomes of mosunetuzumab against seven comparators: axicabtagene ciloleucel (axi-cel), tisagenlecleucel (tisa-cel), tazemetostat (taz, EZH2 wild-type only), rituximab plus lenalidomide (R-Len) or bendamustine (R-Benda), obinutuzumab plus bendamustine (O-Benda), and a retrospective real-world cohort (RW) based on current patterns of care derived from US electronic health records (Flatiron Health). Efficacy data for mosunetuzumab were from the pivotal Phase II GO29781 trial (NCT02500407). Relative treatment efficacy was estimated from indirect treatment comparisons (ITCs). Costs included were related to treatment, adverse events, routine care, and terminal care. Except for drug costs (March 2023), all costs were inflated to 2022 US dollars. Costs and quality-adjusted life-years (QALYs) were used to calculate incremental cost-effectiveness ratios (ICERs). Net monetary benefit (NMB) was calculated using a willingness-to-pay (WTP) threshold of $150,000/QALY. RESULTS: Mosunetuzumab dominated taz, tisa-cel, and axi-cel with greater QALYs and lower costs. Mosunetuzumab was projected to be cost-effective against R-Benda, O-Benda, and RW with ICERs of $78,607, $42,731, and $21,434, respectively. Mosunetuzumab incurred lower costs but lower QALYs vs. R-Len. NMBs showed that mosunetuzumab was cost-effective against comparators except R-Len. LIMITATIONS: Without head-to-head comparative data, the model had to rely on ITCs, some of which were affected by residual bias. Model inputs were obtained from multiple sources. Extensive sensitivity analyses assessed the importance of these uncertainties. CONCLUSION: Mosunetuzumab is estimated to be cost-effective compared with approved regimens except R-Len for the treatment of adults with R/R FL.