NK cell kinetics predict outcome in the multiple treated with elotuzumab, lenalidomide plus dexamethasone (ERd): a subanalysis in Japanese multicenter observation for once monthly ERd study

S212model results indicated that total C_ave,event was not significantly associated (P-value=0.4307) with G3+ neutropenia, however, free C_ave,event was significant (P-value=0.0272).For infections, total C_ave,event was not significantly associated with G3+ infections (P-value=0.1918),however, free C_ave,event was significant (P-value=0.0362).Neither the exposure metrics nor the clinical or laboratory covariates were retained in the final models after backward elimination.For peripheral neuropathy, the analysis dataset included a total of 29 events of G2+ peripheral neuropathy which did not allow for a statistical analysis.However, there was no apparent ER relationship by visual inspection of diagnostic plots and exposure in participants with G2+ peripheral neuropathy was within the range of those without events.Conclusions: No statistically significant relationship was observed between elranatamab exposure (free or total Cave,event) and the incidence of G3+ AEs of neutropenia/infection and G2+ peripheral neuropathy.Elranatamab demonstrated a relatively flat exposure-safety profile.This finding together with the meaningful clinical benefit observed in the MagnetisMM-3 study indicates a favorable benefit-risk for elranatamab at the 76 mg QW/ Q2W regimen.