(306) Life-year and quality-adjusted life-year results from a United States cost-effectiveness model for belantamab mafodotin, bortezomib, and dexamethasone in relapsed/refractory multiple myeloma

Background: : The phase 3 DREAMM-7 study (NCT04246047) demonstrated significant improvement in progression-free and overall survival with belantamab mafodotin, bortezomib, and dexamethasone (BVd) vs daratumumab, bortezomib, and dexamethasone (DVd) in patients with relapsed/refractory multiple myeloma (RRMM) who received ≥1 prior line of therapy.

Objective: : To measure the value of BVd vs that of alternative treatment options, a de novo US cost-effectiveness model was developed to estimate life years (LYs) and quality-adjusted LYs (QALYs) for BVd vs relevant comparator treatments in RRMM in the second-line or later.

Methods: : A de novo partitioned survival model with 4 health states (progression-free disease on treatment, progression-free disease off treatment, progressed disease, and death) evaluated BVd vs 7 comparators: carfilzomib and dexamethasone (Kd), daratumumab and Kd (DKd), DVd, isatuximab and Kd (Isa-Kd), pomalidomide and Vd, and selinexor and Vd, and Vd. The model used a 1-week cycle length with a US Medicare perspective over a lifetime horizon, and discounted outcomes at 3.0%. Efficacy data for BVd and DVd were sourced from DREAMM-7, while relative treatment effects for other comparators were informed by a network meta-analysis. Health utilities were informed by DREAMM-7 EQ-5D-3L data, and adverse event disutilities were sourced from previous Institute for Clinical and Economic Review reports and supplemented with National Institute for Health and Care Excellence appraisals. The incidence of grade ≥3 adverse events based on trial data was used to calculate the disutilities for each comparator. Sensitivity analyses (deterministic and probabilistic) explored the level of uncertainty of the results. The overall intention-to-treat (ITT) population and subpopulations (second line, lenalidomide refractory, and lenalidomide exposed) were evaluated.

Results: : In the ITT population, BVd resulted in the highest LYs (9.2) and QALYs (7.5) among all treatments. LYs for comparators ranged from 4.9 (Vd) to 7.8 (Isa-Kd and DKd). QALYs for comparators ranged from 4.0 (Vd) to 6.3 (Isa-Kd and DKd). Subgroup results were consistent with those from the ITT population.

Conclusions: : BVd consistently resulted in the highest LYs and QALYs.

Sponsorship:: GSK. Drug-linker technology licensed from Seagen Inc; monoclonal antibody produced using POTELLIGENT Technology, licensed from BioWa.