Background: RRMM patients (pts) previously exposed to bortezomib (BORT) and lenalidomide (LEN) have short overall survival (OS). The phase 3 MM-003 trial (NCT01311687) demonstrated significantly longer OS in RRMM pts treated with POM + LoDEX vs HiDEX (HR, 0.74 [95% CI, 0.56-0.97], P = .0285). This post hoc analysis investigated OS based on the response status of pts at different cycles. Methods: Landmark analyses at the start of cycles (C) 3, 5, and 7 were performed using Kaplan-Meier methods and unadjusted Cox regression models. Time-dependent survival analyses captured response status over time. For both approaches, survival of ptswith stable disease (SD) was compared to that of pts with progressive disease (PD) or overall response (OR; ≥ partial response). Results: At C3, 38.4% of pts (116/302) randomized to POM + LoDEX attained SD, 14.6% PD, and 19.2% OR; 28% had no response data, most due to early discontinuation. The median OS from randomization by response status at C3 was 15.3 mos for SD, 6.3 for PD, and 17.5 for OR. The difference in OS at C3 between pts with PD or SD was significant (P < .001); that between pts with OR or SD was not (P = .32). A similar pattern was observed at C5 and C7. The time-dependent survival model showed a lower risk of death for pts with SD or OR vs PD (HR, 0.27 [95% CI, 0.17-0.44] and HR, 0.06 [95% CI, 0.02-0.16], respectively). For the HiDEX arm, small pt numbers per group (due to the lower response rate, 2:1 randomization, and shorter OS vs POM + LoDEX) made interpretation challenging. Conclusions: In the POM + LoDEX group, pts with SD at C3, C5, and C7 had OS comparable to pts who achieved a response by those times. Pts with either SD or OR had a longer OS than those with PD at the same time points. Clinical trial information: NCT01311687