Results: Between December 1st, 2020, and March 2nd, 2022, a total of 102 patients were enrolled. Overall, the median age was 59.5 years (range: 38 to 75) with 31 (30.4%) patients aged 65 years or older, 39 (38.2%) patients had ISS Stage III and 61 (59.8%) patients had high-risk cytogenetics.

The objective response rate (ORR) was 92.2% (95% CI: 85.13, 96.55) for the whole study population; 73 (71.6%) patients achieved stringent complete response (sCR, n=69) or complete response (CR, n=4), 20 (19.6%) achieved very good partial response (VGPR), 1 (1.0%) achieved partial response (PR). The ORR or the CR/sCR rate was not affected by any of the baseline characteristics tested: In age-based subgroups, ORR and CR/sCR rate for ＜65yrs versus ≥ 65yrs were 93.0% (66/71) versus 90.3% (28/31) and 71.8% (51/71) versus 71.0% (22/31), respectively. In ISS-based subgroups, ORR and CR/sCR rate for ISS I/II versus ISS III were 89.7% (35/39) versus 93.7% (59/63) and 61.5% (24/39) versus 77.8% (49/63), respectively. Subgroup without high-risk cytogenetics had ORR and CR/sCR rates of 90.2% (37/41) and 73.2% (30/41), respectively, compared to ORR and CR/sCR rate of 93.4% (57/61) and 70.5% (43/61), respectively in patients with high-risk cytogenetics.

With a median follow-up of 20.3 (range: 0.4 to 27) months, the median duration of response (DOR), progression-free survival (PFS), and overall survival (OS) data were not mature and therefore, 18-month (18m) and estimated 30-month (30m) event free rates were used as efficacy outcomes for subgroup analyses. The DOR, PFS and OS were not impacted by age or ISS. In the age-based subgroups ＜65yrs versus ≥ 65yrs, 18m DOR rate was 62% versus 60%, 18m PFS rate was 63% versus 58% and the estimated 30m OS rate was 81% versus 77%. In ISS-based subgroups I/II versus III, 18m DOR rate was 57% versus 64%, 18m PFS rate was 58% versus 63% the estimated 30-month OS rate was 76% versus 81%. There was a trend towards favorable outcomes which was seen in patients without high-risk cytogenetics compared to those with high-risk cytogenetics: 18m DOR rate of 66% versus 58%, 18m PFS rate of 69% versus 56% and an estimated 30m OS rate of 85% versus 76%, however, none of these differences were statistically significant.

Conclusion: The subgroup analyses of the pivotal Phase II stage of LUMMICAR STUDY 1 indicated that the clinical efficacy of zevor‑cel is not significantly impacted by baseline characteristics suggesting that even patients with RRMM with poor prognostic factors may benefit from zevor-cel.