PCN69 COST-EFFECTIVENESS OF DARATUMUMAB ADDED TO LENALIDOMIDE AND DEXAMETHASONE FOR TRANSPLANT INELIGIBLE MULTIPLE MYELOMA

Abstract

Multiple Myeloma survival rates are steadily increasing due to availability of new drug classes used in combinations with corticosteroids and chemotherapy. Daratumumab is a CD38-targeted, human IgG1k monoclonal antibody approved as combination with standard of care regimens for transplant-ineligible newly diagnosed multiple myeloma (NDMM). For this reason, we wanted to determine the cost-effectiveness of daratumumab added to the standard of care of lenalidomide plus dexamethasone (Rd) regimen compared to standard therapy alone in transplant-ineligible NDMM. A two-state Markov model (‘stable disease’, progression and/or death’) was developed using a US societal perspective and 10 year lifetime time horizon. Transition probabilities were calculated from the latest progression-free survival data reported in the phase 3 MAIA trial and extrapolated using a Weibull distribution based on the Hoyle Henley method. National costs were in 2019 US dollars. Adverse event (AE) management was determined using MAIA trial data and disease treatment guidelines. Base case, one-way, and probabilistic sensitivity analyses were conducted. Daratumumab therapy (DRd) had a high incremental cost effectiveness ratio (ICER) ($364,990 per progression-free life-year [PFLY]) compared to standard (Rd) care in our base case analysis; assuming a willingness-to-pay threshold of $100,000/PFLY. Triple drug therapy was much more costly than standard therapy ($22,570/month vs. $16,163/month). Sensitivity analysis showed our model was sensitive to drug costs and changes in progression rates and costs. Two-way sensitivity analysis showed that DRd therapy reaches under the WTP limit when Rd progression costs are $2,667/month more than DRd progression costs. The results demonstrate a high ICER per PFLY for Triple therapy with Daratumumab vs standard care. An additional 5 months of unpublished PFS data matches our Weibull models. As overall survival data becomes available, a more accurate ICER threshold can be demonstrated. Cost of drug and progression drive our results.