Table 1 Baseline characteristics

Age at diagnosis, years, median (range)

56 (34–71)

Age at clinical trial screening, years, median (range)

59 (35–73)

Diagnosis to clinical trial screening, months, median (range)

26 (3–101)

Male, N (%)

22 (68.8)

Extramedullary disease at diagnosis, N (%)

18 (56.3)

Extramedullary disease at enrollment, N (%)

32 (100.0)

ISS at diagnosis, N (%)

 I/II/III

7 (21.9)/ 14(43.7) / 11(34.4)

R-ISS at diagnosis, N (%)

 I/II/III/unknown

3 (9.4)/ 7(21.9)/ 13(40.6) /9(28.1)

High risk, N (%)

Available in 23 patients 16/23 (69.6%)

 t(4;14)

6/23 (26.1)

 del(17p)

4/23 (17.4)

 t(14;16)

6/23 (26.1)

Number of prior lines of treatment, median (range)

3 (1–5)

Prior ASCT, N (%)

19 (59.4)

Prior proteasome inhibitor use, N (%)

 Bortezomib

32 (100)

 Carfilzomib

25 (78.1)

 Ixazomib

2 (6.3)

Prior IMiDs use, N (%)

 Thalidomide

25 (78.1)

 Lenalidomide

29 (90.6)

 Pomalidomide

14 (43.8)

Prior alkylator exposure, N (%)

16 (50.0)

Refractory to proteasome inhibitor, N (%)

28 (84.5)

Refractory to IMiDs, N (%)

30 (93.8)

Double refractory, N (%)

27 (84.4)

ECOG performance at enrollment, N (%)

 0/1/2

7(21.9) / 19(59.4)/ 6(18.8)

Laboratory findings at enrollment, mean (standard deviation)

 Hemoglobin, g/dL

13.5 (1.8)

 WBC, × 10⁹/L

5.7 (5.2)

 ALC, × 10⁹/L

1.5 (1.5)

 ANC, × 10⁹/L

2.8 (1.6)

 Platelet, × 10⁹/L

171.7 (104.6)