Table 3.

Adverse events

		CD24Fc group (n=114)	Placebo group (n=115)
Total adverse events		69	52
Participants with adverse events		32 (28%)	35 (30%)
Treatment-related adverse events		0	0
Participants with treatment-related adverse events		0	0
Total serious adverse events		37	32
Participants with serious adverse events		26 (23%)	27 (24%)
Deaths		16 (14%)	18 (15%)
Total fatal serious adverse events		17	19
Participants with fatal serious adverse events		15 (13%)	18 (16%)
Fatal serious adverse events*
	Respiratory, thoracic, and mediastinal disorders	7 (6%)	13 (11%)
	Respiratory failure	5 (4%)	12 (10%)
	Cardiac disorders	6 (5%)	3 (3%)
	Cardiac arrest	3 (3%)	2 (2%)
Total non-fatal serious adverse events		22	15
Participants with non-fatal serious adverse events		17 (15%)	12 (10%)
Non-fatal serious adverse events*
	Respiratory, thoracic, and mediastinal disorders	7 (6%)	7 (6%)
	Respiratory failure	0	3 (3%)
	Blood and lymphatic system disorders	3 (3%)	1 (1%)
	Anaemia	3 (3%)	1 (1%)
	Renal and urinary disorders	3 (3%)	1 (1%)
	Acute kidney injury	3 (3%)	1 (1%)
Grade ≥3 adverse events by system organ class*
Blood and lymphatic system disorders
	Acute anaemia	0	1 (1%)
	Acute exacerbation of chronic anaemia	1 (1%)	0
	Anaemia	5 (4%)	1 (1%)
	Worsening of anaemia	1 (1%)	0
Cardiac disorders
	Asystole arrest	1 (1%)	0
	Cardiac arrest	2 (2%)	2 (2%)
Renal and urinary disorders
	Acute kidney injury	1 (1%)	1 (1%)
	Acute renal failure	4 (3%)	1 (1%)
	Oliguric acute renal failure with hyperkalaemia	0	1 (1%)
Respiratory, thoracic, and mediastinal disorders
	Pneumothorax	2 (2%)	1 (1%)
	Right pneumothorax	1 (1%)	0
	Exacerbation of respiratory failure	3 (3%)	7 (6%)
	Hypoxic respiratory failure	0	2 (2%)
	Hypoxic respiratory failure secondary to COVID-19	0	1 (1%)
	Respiratory failure	4 (3%)	6 (5%)

Data are n or n (%). Adverse event assessment period was 28 days from randomisation.

^*With incidence rates of 2% or greater in one or more treatment group, by system organ class in all participants who received study treatment.