Table 2.

Safety characteristics of patients across OL1 [baseline to Week 72], OL2 [Weeks 76–144] and the follow-up period.

	Ontamalimab 75 mg [n = 164]	Ontamalimab 225 mg [n = 166]	Ontamalimab overall [n = 330]
Overall TEAEs by system organ class, n [%]
Any TEAEa	146 [89.0]	147 [88.6]	293 [88.8]
Infections and infestations	96 [58.5]	94 [56.6]	190 [57.6]
General disorders and administration site conditions	43 [26.2]	58 [34.9]	101 [30.6]
Skin and subcutaneous tissue disorders	41 [25.0]	55 [33.1]	96 [29.1]
Gastrointestinal disorders	95 [57.9]	94 [56.6]	189 [57.3]
Nervous system disorders	33 [20.1]	48 [28.9]	81 [24.5]
Respiratory, thoracic, and mediastinal disorders	34 [20.7]	34 [20.5]	68 [20.6]
Musculoskeletal and connective tissue disorders	53 [32.3]	62 [37.3]	115 [34.8]
TEAEs considered related to ontamalimab	58 [35.4]	61 [36.7]	119 [36.1]
TESAEs	34 [20.7]	40 [24.1]	74 [22.4]
Treatment discontinuation due to TEAEsb	12 [7.3]	23 [13.9]	35 [10.6]
Deaths	1 [0.6]	0 [0.0]	1 [0.3]
Individual TEAEs, reported in ≥5% of patients, n [%]
Ulcerative colitisc	55 [33.5]	50 [30.1]	105 [31.8]
Arthralgia	27 [16.5]	30 [18.1]	57 [17.3]
Nasopharyngitis	20 [12.2]	28 [16.9]	48 [14.5]
Upper respiratory tract infection	23 [14.0]	20 [12.0]	43 [13.0]
Headache	17 [10.4]	22 [13.3]	39 [11.8]
Gastroenteritis	19 [11.6]	14 [8.4]	33 [10.0]
Cough	20 [12.2]	11 [6.6]	31 [9.4]
Abdominal pain	9 [5.5]	21 [12.7]	30 [9.1]
Back pain	12 [7.3]	18 [10.8]	30 [9.1]
Nausea	8 [4.9]	20 [12.0]	28 [8.5]
Influenza	8 [4.9]	15 [9.0]	23 [7.0]
Pyrexia	15 [9.1]	7 [4.2]	22 [6.7]
Rash	8 [4.9]	13 [7.8]	21 [6.4]
Urinary tract infection	11 [6.7]	10 [6.0]	21 [6.4]
Diarrhoea	12 [7.3]	7 [4.2]	19 [5.8]
Pharyngitis	2 [1.2]	17 [10.2]	19 [5.8]
Vomiting	11 [6.7]	8 [4.8]	19 [5.8]
Bronchitis	10 [6.1]	8 [4.8]	18 [5.5]
Influenza-like illness	8 [4.9]	9 [5.4]	17 [5.2]
Sinusitis	7 [4.3]	10 [6.0]	17 [5.2]

Treatment groups based on initial randomisation assignment.

OL1, open-label treatment period 1; OL2, open-label treatment period 2; TEAE, treatment-emergent adverse event; TESAE, treatment-emergent serious adverse event.

^aIncludes non-treatment-related TEAEs.

^bIncludes two patients in the 225 mg group who discontinued owing to TEAEs that occurred after the treatment period was completed.

^cWorsening or ongoing disease activity.