Table 1

Characteristics of cases receiving LTG who experienced SJS/TEN; reference group A: cases receiving LTG who experienced non-cutaneous ADRs; and reference group B: cases experiencing SJS/TEN after other drugs

		LTG with SJS/TEN		LTG without cutaneous ADRs, Ref A*			SJS/TEN with other drugs, Ref B
Total number of reports		486		2609			4349
Report features	Report variable	No. rep	%	No. rep	%	log OR (logOR ₀₀₅. logOR ₉₉₅₎ ^†	No. rep	%	log OR (logOR ₀₀₅. logOR ₉₉₅₎ ^†
Sex^‡	Male	205	42.5	1248	49.8	−0.42 (–0.68,–0.17)	2329	54.7	−0.69 (–0.96,–0.44)
	Female	277	57.5	1256	50.2	0.42 (0.19,0.63)	1932	45.3	0.69 (0.46,0.90)
	Unspecified	4	0.8	105	4.0	−1.49 (–3.01,–0.44)	88	2.0	−0.73 (–2.25,0.31)
Age groups	0–27 days	0	0.0	260^**	10.0	−3.56 (–5.77,–2.22)§	12	0.3	−0.34 (–2.56,0.99)
	28 days to 23 months	3	0.6	167	6.4	−2.25 (–3.89,–1.15)§	406	9.3	−2.77 (–4.41,–1.68)§
	2 to 11 years	228	46.9	1068	40.9	0.34 (0.09,0.58)	2456	56.5	−0.54 (–0.80,–0.31)
	12 to 17 years	255	52.5	1114	42.7	0.55 (0.31,0.78)	1475	33.9	1.07 (0.83,1.30) ^§
Report origin by geographical region	North America	244	50.2	1266	48.5	0.10 (–0.15,0.32)	1147	26.4	1.44 (1.20,1.67) ^§
	Europe	158	32.5	1015	38.9	−0.39 (–0.70,–0.11)	1354	31.1	0.09 (-0.22,0.37)
	Asia	45	9.3	162	6.2	0.55 (–0.02,1.04)	1382	31.8	−2.07 (–2.64,–1.59)§
	Latin America	18	3.7	34	1.3	1.04 (0.16,1.74)	85	2.0	0.68 (–0.19,1.38)
	Oceania	13	2.7	103	3.9	−0.44 (–1.45,0.33)	137	3.2	−0.18 (–1.19,0.60)
	Africa	8	1.6	29	1.1	0.33 (–0.89,1.22)	244	5.6	−1.36 (–2.58,–0.47)
Fatal outcome	Yes	15	3.1	107	4.1	−0.33 (–1.28,0.41)	178	4.1	−0.33 (–1.28,0.41)
Top co-reported drugs^¶ with LTG in the primary dataset	Valproic acid	207	42.6	493	18.9	1.60 (1.33,1.84) ^§	181	4.2	3.63 (3.37,3.88) ^§
	Clobazam	21	4.3	115	4.4	−0.02 (–0.84,0.63)	36	0.8	1.55 (0.73,2.21)^§
	Clonazepam	18	3.7	128	4.9	−0.34 (–1.22,0.35)	29	0.7	1.50 (0.62,2.19) ^§
	Amoxicillin	16	3.3	8	0.3	1.70 (0.78,2.43)^§	347	8.0	−1.12 (–2.05,–0.40)
	Levetiracetam	16	3.3	151	5.8	−0.69 (–1.61,0.03)	19	0.4	1.57 (0.65,2.30) ^§
	Quetiapine	16	3.3	60	2.3	0.39 (–0.54,1.11)	6	0.1	1.89 (0.97,2.62) ^§
Top five reported ADRs^¶ in the primary dataset MedDRA	SJS	420	86.4	0	0.0	–	3538	81.4	0.54 (0.35,0.71)
	TEN	101	20.8	0	0.0	–	949	21.8	−0.09 (–0.47,0.26)
	Rash	68	14.0	0	0.0	–	180	4.1	1.66 (1.20,2.07)^§
	Fever	59	12.1	56	2.1	2.16 (1.66,2.59)^§	277	6.4	0.91 (0.41,1.34)
	Blister	33	6.8	0	0.0	–	60	1.4	1.74 (1.08,2.30)^§

↵*Reports with cutaneous ADRs were excluded and defined with the MedDRA system organ class ‘Skin and subcutaneous tissue disorders’.
↵†The relative frequencies of report features for LTG and SJS/TEN were contrasted to the reference groups A and B, using ORs with adaptive statistical shrinkage. LogOR005 is the lower limit of the 99% CI, while logOR995 is the upper limit.
↵‡The denominator for the calculated percentage is based on numbers with a known value.
↵§Significant features were defined as those with logOR005>0.5 (feature in the primary dataset is reported significantly more frequently than in the reference group) or logOR995<−0.5 (feature in the primary dataset is reported less frequently than in the reference group). In this study, key features were defined as those features in the primary dataset that were significantly different from both reference groups A and B, with the exception of co-reported cutaneous reactions where comparison was only relevant to reference group B (since cutaneous reactions had been excluded in reference group A).
↵¶One unique report can be represented within more than one MedDRA preferred term or within more than one drug because one report can be recorded with more than one adverse reaction or drug.
**Many of the reports in the youngest age group concern in utero exposure and congenital anomalies.
ADR, adverse drug reaction; LTG, lamotrigine ; SJS, Stevens-Johnson syndrome; TEN, toxic epidermal necrolysis