Table 3.

Reasons for switching for all biologic switches the study cohort

		Loss of efficacy	Adverse events	Occurrence of a contraindication	Patient decision	Non medical reason	Clearance	Loss of adherence	Unknown	Total (nb of switches)
Total (%)*		740 (72.0%)	111 (10.8%)	55 (5.4%)	36 (3.5%)	11 (1.1%)	14 (1.4%)	8 (0.8%)	121 (11.8%)	1028
Intra‐class switch		151 (20.4%)	30 (27.0%)	9 (16.4%)	7 (19.4%)	3 (27.3%)	1 (7.1%)	1 (12.5%)	21 (17.4%)	211 (20.5%)
	TNFi	120 (79.5%)	20 (66.7%)	7 (77.8%)	6 (85.7%)	3 (100.0%)	1 (100.0%)	1 (100.0%)	12 (57.1%)	161
	IL‐17i	28 (18.5%)	9 (30.0%)	2 (22.2%)	1 (14.3%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	9 (42.9%)	46
	IL‐23i	3 (2.0%)	1 (3.3%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	4
Inter‐class switch		589 (79.6%)	81 (73.0%)	46 (83.6%)	29 (80.6%)	8 (72.7%)	13 (92.9%)	7 (87.5%)	100 (82.6%)	817 (79.5%)
TNFi to	IL‐17i	152 (25.8%)	14 (17.3%)	4 (8.7%)	5 (17.2%)	0 (0.0%)	1 (14.3%)	2 (15.4%)	16 (16.0%)	184
	IL‐12 23i	154 (26.2%)	27 (33.3%)	14 (30.4%)	10 (34.5%)	4 (50.0%)	4 (57.1%)	1 (7.7%)	30 (30.0%)	230
	IL‐23i	40 (6.8%)	5 (6.2%)	3 (6.5%)	2 (6.9%)	0 (0.0%)	1 (14.3%)	4 (30.8%)	7 (7.0%)	58
IL‐17i to	TNFi	24 (4.1%)	3 (3.7%)	4 (8.7%)	1 (3.5%)	0 (0.0%)	0 (0.0%)	1 (7.7%)	5 (5.0%)	36
	IL‐12 23i	10 (1.7%)	3 (3.7%)	5 (10.9%)	1 (3.5%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	17
	IL‐23i	40 (6.8%)	9 (11.1%)	3 (6.5%)	4 (13.8%)	0 (0.0%)	0 (0.0%)	1 (7.7%)	4 (4.0%)	50
IL‐23i to	TNFi	1 (0.2%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	1
	IL‐17i	6 (1.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	2 (2.0%)	8
	IL‐12 23i	0 (0.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	0
IL12‐23i to	TNFi	41 (7.0%)	7 (8.6%)	7 (15.2%)	2 (6.9%)	1 (12.5%)	0 (0.0%)	2 (15.4%)	9 (9.0%)	65
	IL‐17i	74 (12.6%)	9 (11.1%)	5 (10.9%)	1 (3.5%)	1 (12.5%)	1 (14.3%)	0 (0.0%)	15 (15.0%)	99
	IL‐23i	47 (8.0%)	4 (4.9%)	1 (2.2%)	3 (10.3%)	2 (25.0%)	0 (0.0%)	2 (15.4%)	12 (12.0%)	69

^*Total not equal to 100% since patients could have more than one reason for switching.