Table 1 Characteristic of COVID-19 cases receiving tixagevimab/cilgavimab prophylaxis and their matched-paired controls

Sex

 Female/male

20/27

42.6%/57.4%

19/26

42.2%/57.8%

19/26

42.2%/57.8%

1.000

 Age, in years, median (IQR) [range]

69 (62–79) [41–87]

69 (62–79) [41–84]

72 (63–77) [45–84]

0.948

Comorbidities

 At least one comorbidity

28

59.6%

27

60.0%

33

73.3%

0.263

 No risk factor identified

19

40.4%

18

40.0%

12

26.7%

Baseline malignancy

 Non-Hodgkin lymphoma

29

61.7%

29

64.4%

29

64.4%

1.000

 Multiple myeloma

7

14.9%

6

13.3%

6

13.3%

 Chronic lymphoid leukemia

5

10.6%

5

11.1%

5

11.1%

 Acute myeloid leukemia

2

4.3%

2

4.4%

2

4.4%

 Hodgkin lymphoma

2

4.3%

1

2.2%

1

2.2%

 Acute lymphoblastic leukemia

1

2.1%

1

2.2%

1

2.2%

 Myelodysplastic syndrome

1

2.1%

1

2.2%

1

2.2%

Last malignancy treatment before prophylactic tixagevimab/cilgavimab

 Immuno-chemotherapy

24

51.1%

 Targeted agents

4

8.4%

 Immunotherapy

2

4.3%

 Conventional chemotherapy

2

4.3%

 CAR-T

2

4.3%

 ASCT

1

2.1%

 No treatment

5

10.6%

 Unknown

7

14.9%

Malignancy status at COVID-19 onset

 Controlled disease

31

66.0%

30

66.7%

30

66.7%

1.000

 Stable disease

6

12.8%

5

11.1%

5

11.1%

 Active disease

10

21.3%

10

22.2%

10

22.2%

Anti-SARS-CoV-2 vaccine doses before prophylactic tixagevimab/cilgavimab

 Not vaccinated

7

14.9%

 1 dose

3

6.4%

 ≥ 2 doses

37

78.7%

Anti-SARS-CoV-2 vaccine doses before COVID-19

 Not vaccinated

7

15.6%

7

15.6%

1.000

 One dose

0

0.0%

0

0.0%

 Two doses

5

11.1%

5

11.1%

 Three doses

26

57.8%

26

57.8%

 Four doses

7

15.6%

7

15.6%

Time from tixagevimab/cilgavimab to COVID-19, in days, median (IQR) [range]

40 (18–85) [2–167]

COVID-19 severity

 Asymptomatic

5

10.6%

5

11.1%

7

15.6%

0.525

 Mild/Moderate

32

68.1%

10

22.2%

6

13.3%

 Severe

7

14.9%

27

60.0%

26

57.8%

 Critical

3

6.4%

3

6.7%

6

13.3%

Stay during COVID-19

 Home

37

78.7%

35

77.8%

18

40.0%

0.001

 Hospital

10

21.3%

7

15.6%

21

46.7%

ICU admission

3

6.4%

3

6.7%

6

13.3%

Days of hospital stay, median (IQR) [range]

10.5 (5–24) [4–30]

13 (9–31) [4–68]

10 (4–20) [1–48]

0.242

COVID-19 treatment

 Antivirals

15

31.9%

17

37.8%

24

53.3%

0.024

 Corticosteroids alone

16

34.0%

15

33.3%

5

11.1%

 Monoclonal antibodies ± antivirals ± corticosteroids

5

10.6%

5

11.1%

3

6.7%

 No treatment

11

23.4%

8

17.8%

13

28.9%

Follow up days since prophylactic tixagevimab/cilgavimab

109 (73–122) [28–177]

Outcome

 Alive

45

95.7%

43

95.6%

39

86.7%

0.266

 Dead

2

4.3%

2

4.4%

6

13.3%