Cost-effectiveness of adding daratumumab or bortezomib to lenalidomide plus dexamethasone for newly diagnosed multiple myeloma

BACKGROUND: Multiple myeloma survival rates are steadily increasing due to availability of new drug classes used in combination with corticosteroids and chemotherapy. The latest treatments are daratumumab or bortezomib in combination therapy with lenalidomide and dexamethasone (Rd). Daratumumab, a CD38-targeted, human IgG1k monoclonal antibody, and bortezomib, a proteasome inhibitor, are both approved as regimens for transplant-ineligible relapsed/refractory multiple myeloma (RRMM). There have been cost-effectiveness analyses for daratumumab and bortezomib use in RRMM, but there are limited data regarding cost-effectiveness for daratumumab or bortezomib use in newly diagnosed multiple myeloma patients who are ineligible for stem cell transplantation. OBJECTIVE: To compare the cost-effectiveness of 3 separate regimens-(1) daratumumab, lenalidomide, and dexamethasone triple therapy (DRd); (2) bortezomib and lenalidomide plus dexamethasone triple therapy (VRd); and (3) lenalidomide plus dexamethasone (Rd)-in patients with multiple myeloma ineligible for autologous stem cell transplant. METHODS: A 2-state Markov model was developed using a US health system perspective and lifetime time horizon. Transition probabilities were calculated from the latest progression-free survival data reported in two phase 3 randomized controlled trials-MAIA and SWOG S0777-and extrapolated using a Weibull distribution based on the Hoyle Henley method. National data sources were used to obtain costs in 2019 US dollars, discounted by 3%. Health state utilities from available literature were applied to each health state. Utility decrements for adverse events were individualized in each choice branch with utility decrement weighted by the percentage of patients who experienced the adverse event in the MAIA and SWOG S0777 trials. We assumed a treatment would be cost-effective at a willingness to pay (WTP) of $150,000 per progression-free quality-adjusted life-year ($/PFQALY). One-way and probabilistic sensitivity analyses were conducted. RESULTS: Rd standard therapy had the lowest overall cost at $329,867, followed by VRd at $385,434 and DRd with the highest overall total cost at $626,900. Rd was estimated to result in the least amount (1.24) of PFQALYs, followed by VRd at 1.35 PFQALYs and DRd at 1.52 PFQALYs. With a WTP threshold of $ 150,000 per PFQALY, VRd was not cost-effective compared with Rd standard therapy, with an incremental cost-effectiveness ratio (ICER) of $530,256 per PFQALY. DRd was not cost-effective compared with VRd (ICER = $1,396,318 per PFQALY), nor as compared with Rd standard therapy (ICER =$1060,832). One-way sensitivity analysis showed that our model was sensitive to cost of DRd, VRd, and Rd drugs. Probabilistic sensitivity analysis showed that only at a WTP threshold of $550,000 was VRd cost-effective for 40% of iterations. There were no reasonable WTP thresholds, up to $800,00, where DRd became more cost-effective than VRd. CONCLUSIONS: This study is the first analysis to directly compare the cost-effectiveness of 3 acceptable chemotherapy treatment regimens for patients with multiple myeloma ineligible for autologous stem cell transplant. Neither DRd nor VRd triple therapy were found to be cost-effective vs Rd. Further cost-effectiveness analyses that include overall survival data for daratumumab and bortezomib triple therapies are needed to demonstrate an ICER in QALYs.