In this issue of Blood, Kumar et al and Richardson et al report the results of 2 phase 1 trials that investigated 2 different administration schedules of ixazomib in patients with relapsed/refractory multiple myeloma (MM): weekly and biweekly dosing., Kumar et al determined that the maximum tolerated dose (MTD) of single-agent oral ixazomib given weekly for 3 of 4 weeks was 2.97 mg/m2. Detailed pharmacokinetic analyses showed that after multiple dosing, the terminal half-life was long (3.6-11.3 days), supporting once-weekly dosing. In the trial by Richardson et al, the MTD of single-agent, oral ixazomib, given on days 1, 4, 8, 11 of a 21-day cycle was found to be 2 mg/m2.