Table 2.

Summary of safety assessments in all participants who received at least one study injection

		Tetravalent (n=110)	Trivalent (n=55)	Placebo (n=33)
Serious adverse events
	Any	6 (6%)	0	0
	Angina pectoris and acoustic neuroma	1 (1%)	0	0
	Atrial fibrillation	1 (1%)	0	0
	Ankle fracture	1 (1%)	0	0
	Rheumatoid arthritis	1 (1%)	0	0
	Syncope	1 (1%)	0	0
	Lymphoedema	1 (1%)	0	0
Adverse event leading to vaccine discontinuation		0	1 (2%)*	2 (6%)†
Grade 3 solicited adverse events
	Any local	2 (2%)	6 (11%)	1 (3%)
	Any systemic	25 (23%)	13 (24%)	1 (3%)
Unsolicited adverse events within 28 days of any dose
	Any	74 (67%)	35 (64%)	23 (70%)
	Related	5 (5%)	4 (7%)	3 (9%)
	Grade 3	2 (2%)	3 (5%)	0
Abnormal vital signs
	Bradycardia	15 (14%)	9 (16%)	7 (21%)
	Hypertension	15 (14%)	5 (9%)	5 (15%)

Data are n (%).

^*Hepatitis C infection.

^†Urticaria and viral infection. There were no adverse events of special interest.