. 2021 Dec 10;3(1):97–108. doi: 10.1002/jha2.312

TABLE 1.

Overview of baseline characteristics before and after adjustment with IPTW for the base case

		Unadjusted	Adjusted
Variables used in adjustment with IPTW for the base case
Refractory status ^b	Penta refractory ^c Triple or quad refractory ^d Others	41 (42.3) 44 (45.4) 12 (12.4)	177 (52.7) 130 (38.7) 29 (8.6)	37 (46.3) 36 (45.5) 7 (8.2)
ISS stage	I II III	61 (62.9) 22 (22.7) 14 (14.4)	120 (35.7) ^e 106 (31.5) ^e 110 (32.7) ^e	53 (66.7) 16 (20.6) 10 (12.7)
Cytogenetic profile	High risk ^f Standard risk Unknown	23 (23.7) 68 (70.1) 6 (6.2)	62 (18.5) 181 (53.9) 93 (27.7)	17 (21.8) 58 (72.1) 5 (6.1)
Time to progression on last regimen	≤4 months >4 months	48 (49.5) 49 (50.5)	101 (30.1) 235 (69.9)	40 (50.5) 40 (49.5)
Presence of total plasmacytoma ^g	No Yes	78 (80.0) 19 (20.0)	NR NR	NR NR
Number of prior LOTs	≤4 >4	33 (34.0) 64 (66.0)	65 (19.3) 271 (80.7)	24 (29.8) 56 (70.2)
Years since MM diagnosis	<6 ≥6	45 (46.4) 52 (53.6)	259 (77.1) 77 (22.9)	38 (47.6) 42 (52.4)
Age	<65 ≥65	62 (63.9) 35 (36.1)	129 (38.4) 207 (61.6)	51 (63.2) 29 (36.8)
Variables not used in adjustment with IPTW for the base case
Hemoglobin (g/dL)	<12 ≥12	90 (92.8) 7 (7.2)	249 (74.1) ^h 87 (25.9) ^h	59 (74.1) 21 (25.9)
LDH levels (units/L)	<280 ≥280	85 (87.6) 12 (12.4)	284 (84.5) ⁱ 52 (15.5) ⁱ	67 (83.4) 13 (16.6)
Prior stem cell transplant	No Yes	10 (10.3) 87 (89.7)	137 (40.8) 199 (59.2)	21 (24.5) 60 (75.5)
ECOG status	0 1	39 (40.2) 58 (59.8)	98 (29.2) ^j 238 (70.8) ^j	33 (40.8) 50 (58.5)
Race	White Black/African American Not reported/other	69 (71.1) 17 (17.5) 11 (11.3)	233 (69.3) 48 (14.3) 55 (16.4)	57 (71.5) 13 (16.3) 10 (12.2)
Sex	Female Male	40 (41.2) 57 (58.8)	151 (44.9) 185 (55.1)	32 (39.6) 48 (60.4)
Type of MM	IgG Light chain Other	57 (58.8) 24 (24.7) 16 (16.5)	198 (58.9) 58 (17.3) 80 (23.8)	48 (59.5) 16 (20.3) 16 (20.2)

Unadjusted

Adjusted

Variable

Categories

CARTITUDE‐1, N (%) 97 (100%)

RW cohort, N _OBS (%) 336 (100%)

RW cohort, ESS ^a (%) 80 (100%)

Variables used in adjustment with IPTW for the base case

Refractory status ^b

Penta refractory ^c

Triple or quad refractory ^d

Others

41 (42.3)

44 (45.4)

12 (12.4)

177 (52.7)

130 (38.7)

29 (8.6)

37 (46.3)

36 (45.5)

7 (8.2)

ISS stage

III

61 (62.9)

22 (22.7)

14 (14.4)

120 (35.7) ^e

106 (31.5) ^e

110 (32.7) ^e

53 (66.7)

16 (20.6)

10 (12.7)

Cytogenetic profile

High risk ^f

Standard risk

Unknown

23 (23.7)

68 (70.1)

6 (6.2)

62 (18.5)

181 (53.9)

93 (27.7)

17 (21.8)

58 (72.1)

5 (6.1)

Time to progression on last regimen

≤4 months

>4 months

48 (49.5)

49 (50.5)

101 (30.1)

235 (69.9)

40 (50.5)

40 (49.5)

Presence of total plasmacytoma ^g

Yes

78 (80.0)

19 (20.0)

Number of prior LOTs

≤4

33 (34.0)

64 (66.0)

65 (19.3)

271 (80.7)

24 (29.8)

56 (70.2)

Years since MM diagnosis

≥6

45 (46.4)

52 (53.6)

259 (77.1)

77 (22.9)

38 (47.6)

42 (52.4)

Age

<65

≥65

62 (63.9)

35 (36.1)

129 (38.4)

207 (61.6)

51 (63.2)

29 (36.8)

Variables not used in adjustment with IPTW for the base case

Hemoglobin (g/dL)

<12

≥12

90 (92.8)

7 (7.2)

249 (74.1) ^h

87 (25.9) ^h

59 (74.1)

21 (25.9)

LDH levels (units/L)

<280

≥280

85 (87.6)

12 (12.4)

284 (84.5) ⁱ

52 (15.5) ⁱ

67 (83.4)

13 (16.6)

Prior stem cell transplant

Yes

10 (10.3)

87 (89.7)

137 (40.8)

199 (59.2)

21 (24.5)

60 (75.5)

ECOG status

39 (40.2)

58 (59.8)

98 (29.2) ^j

238 (70.8) ^j

33 (40.8)

50 (58.5)

Race

White

Black/African American

Not reported/other

69 (71.1)

17 (17.5)

11 (11.3)

233 (69.3)

48 (14.3)

55 (16.4)

57 (71.5)

13 (16.3)

10 (12.2)

Sex

Female

Male

40 (41.2)

57 (58.8)

151 (44.9)

185 (55.1)

32 (39.6)

48 (60.4)

Type of MM

IgG

Light chain

Other

57 (58.8)

24 (24.7)

16 (16.5)

198 (58.9)

58 (17.3)

80 (23.8)

48 (59.5)

16 (20.3)

16 (20.2)

^{^a}

ESS was rounded to whole numbers.

^{^b}

Refractoriness was defined as discontinuation of drug of interest within 60 days and starting a different drug in the next line or starting a new drug within 60 days after end of previous treatment (RW cohort) and by International Myeloma Working Group consensus criteria (CARTITUDE‐1) [7, 21].

^{^c}

Refractory to at least two IMiDs, two PIs, and an anti‐CD38 MoAB.

^{^d}

Refractory to two IMiDs and one PI; or two PIs and one IMiD; or two IMiDs and two PIs.

^{^e}

ISS stage was imputed for 96 observations in the RW cohort.

^{^f}

At least one of del17p, t(14;16), or t(4;14).

^{^g}

Includes extramedullary plasmacytomas and soft‐tissue components of bone‐based plasmacytomas [24].

^{^h}

Hemoglobin was imputed for 1 observation in the RW cohort.

^ⁱ

LDH was imputed for 97 observations in the RW cohort.

^{^j}

ECOG was imputed for 84 observations in the RW cohort.

Abbreviations: ATT, average treatment effect in the treated; ECOG, Eastern Cooperative Oncology Group; ESS, effective sample size; IMiD, immunomodulatory drug; IPTW, inverse probability of treatment weighting; ISS, International Staging System; LDH, lactate dehydrogenase; LOTs, lines of therapy; MM, multiple myeloma; MoAB, monoclonal antibody; N _OBS, number of observations; NR, not reported; PI, proteasome inhibitor; RW, real world; SMD, standardized mean difference.