Kaplan-Meier survival curves for disseminated models. Mice bearing disseminated MM xenografts were treated on day 0 with ²¹¹At-CD38 or ²¹¹At-Ab⁻; n = 9 to 10 mice per group. Disease progression was monitored via weekly BLI and thrice weekly observations of mouse weight, condition, and mobility. Mice were euthanized when they experienced hind-limb paralysis or met IACUC weight loss or condition requirements. Statistics report Kaplan-Meier proportional hazards tests. (A) MOLP-8^Luc model, treated at 12, 20, and 28 µCi. Across treatment levels, ²¹¹At-CD38 therapy strongly benefitted survival relative to untreated controls (P < .00001) and to ²¹¹At-Ab⁻ groups (P < .00001) in a dose-dependent manner (P < .00001). (B) OPM-2^Luc model, treated at 15, 30, and 45 µCi. ²¹¹At-CD38 therapy strongly improved survival across groups, relative to untreated controls (P < .00001) and to ²¹¹At-Ab⁻ treatments (P = .00002) in a dose-dependent manner (P < .00001). Additional statistics in “Results.” (C) NCI-H929^Luc model, treated at 8, 18, or 24 µCi. Mice treated with ²¹¹At-CD38 survived significantly longer than untreated control (P < .0001) and ²¹¹At-Ab⁻ treated mice (P < .0006). Treatment benefits were dose-dependent with higher ²¹¹At dosing improving survival (P < .002).