Benefit-risk preferences for treatments for newly-diagnosed multiple myeloma.

320 Background: Clinical studies are generating evidence on benefits and risks of emerging, novel treatments, including bispecifics and CAR-T, for newly diagnosed patients with multiple myeloma (MM) who are not candidates for stem-cell transplant (SCT). This study quantified the extent to which patients would accept short-term risks following MM therapy for the potential benefit of a longer, treatment-free interval. Methods: Adult patients with MM from the Duke Cancer Institute Tumor Registry were invited to complete an online discrete-choice experiment (DCE) survey in which they were to suppose they had a friend (same age and gender) recently diagnosed with MM who is not a candidate for SCT. Respondents chose the better post-induction therapy treatment for their friend from pairs of experimentally designed hypothetical treatments. In each question, treatments varied in terms of time until relapse (3, 5, or 10 years), impact of treatment-related side effects on daily activities (no, minor, or moderate limits), treatment-related mortality (0% to 10% in the first 3 months), and risk of reversible, short-term side effects (described as neurotoxicity or cytokine release syndrome) resulting in a 10-day hospitalization (0% to 20% risk in the first 3 months). DCE data were analyzed with a random-parameters logit model to estimate preference weights (PW) which were used to estimate the maximum level of short-term mortality risk acceptable to patients for longer time to relapse and less impact on daily activities. Results: The survey was completed by 176 patients (mean age; 66 yrs; 51% female, 22% Black) of whom 80% had a transplant and 31% had at least one relapse. Responses to the DCE were logically ordered (patients preferred lower levels of risks and better levels of benefit). For the levels specified, avoiding treatment-related mortality was most important (PW: 3.69), followed by gaining relapse-free years (PW: 3.32), and reducing impact on daily activities (PW: 2.04). Risk of reversible, short-term side effects was relatively least important (PW: 0.58). All else equal, patients would accept 5.7% mortality (95% CI: 3.8-7.2) for a 2-year gain in time to relapse (from 3 to 5 yrs) or 6.0% mortality risk (95% CI: 4.5-7.3) to avoid side effects that moderately limit their daily activities. Conclusions: Patients considering initial treatment following induction therapy for MM assigned least importance to reversible, short-term side effects that may be associated with CAR-T. Specified levels of treatment mortality were acceptable in exchange for longer relapse free intervals and fewer impacts on daily activities.[Table: see text]