PS1516 COST‐EFFECTIVENESS OF RISK‐STRATIFIED TREATMENT IN TRANSPLANT‐ELIGIBLE PATIENTS WITH MULTIPLE MYELOMA
Authors: Van Dongen ‐ Leunis A. , Sajjad A. , Valent E. , van Vliet M. , van Beers E. , Sonneveld P. , Redekop K. 
Published: June 2019

Background:Many different treatment regimens are currently available for Multiple Myeloma (MM) patients. There is ongoing research to identify subgroups of patients who may benefit from specific treatments. Recently, it was found that patients with low‐risk MM (SKY92 standard‐risk, ISS stage I, and no del(17p)) had a better overall survival after receiving Bortezomib, Melphalan and Prednisone (VMP) combination therapy compared to High‐dose Melphalan therapy followed by an autologous stem cell transplantation (HDM+ASCT)(Hofste op Bruinink et al. 2018, The American Society of Hematology, # 3186). Clinicians may consider a risk‐stratified treatment approach based on SKY92, ISS, and del(17p) status for transplant‐eligible MM patients instead of treating all transplant‐eligible patients with HDM+ASCT.Aims:We evaluated the cost‐effectiveness of a risk‐stratified treatment approach for transplant‐eligible MM patients in which low‐risk individuals are directly treated with combination therapy instead of HDM+ASCT. All others patients will receive HDM+ASCT as initial treatment.Methods:The cost‐effectiveness analysis was restricted to the low‐risk patient group because risk stratification only led to a therapy change for this subgroup. A decision model was developed consisting of three health states: progression‐free survival, progressive disease and death. A partitioned survival model, based on Kaplan‐Meier curves reported by Hofste op Bruinink et al. (2018), was used to estimate the proportion of patients in each health state over time. Quality of life utilities and costs were derived from literature. Costs consisted of additional testing costs, initial treatment costs, maintenance treatment costs and costs of progressive disease. It was assumed that all patients received maintenance treatment until disease progression and that second and further‐line treatments were identical for both VMP and HDM+ASCT. The main outcome of the analysis was the incremental costs per life year or quality‐adjusted life year (QALY) gained. The analysis was performed from a Dutch health care perspective (in 2018 Euros) with a lifetime horizon.Results:26% of all transplant‐eligible patients were classified as low‐risk. In these patients, VMP resulted in better health outcomes compared to HDM+ASCT. The difference in life years was 9.6 years (VMP: 21.3 years, HDM+ASCT: 11.7 years). The QALY gain was 6.4 QALY (VMP: 14.8, HDM+ASCT: 8.4 QALYs). Initial treatment costs were almost similar for the two treatments, but the costs of maintenance treatment and progressive disease were substantially larger for VMP due to a longer life expectancy. The total difference in costs was €345,000 (VMP: €876,245, HDM+ASCT: €531,245). The incremental cost‐effectiveness ratio was €35,677 per life year gained and €54,005 per QALY gained.Summary/Conclusion:The proposed risk‐stratified treatment approach resulted in substantial survival and QALY gain. However, this health gain is also associated with higher costs due to continuous maintenance treatment until progression and expensive treatments for patients with progressive disease. Nevertheless, the risk‐stratified treatment is expected to be cost‐effective. If low‐risk patients can also achieve satisfying outcomes with less intensive maintenance and relapse treatment, the risk‐stratified treatment may become even more cost‐effective.