TABLE S1.Median progression-free survival according to treatment arm, EGFR mutation group and EGFR expression group
Populationa / Chemotherapy+ cetuximab / Chemotherapy
alone
n / Median, months
(95%CI) / n / Median, months
(95%CI)
ITT
All patients
Low EGFR IHC score
High EGFR IHC score / 557
377
178 / 4.8 (4.2–5.3)
4.6 (4.1–5.3)
5.0 (4.2–5.5) / 568
399
167 / 4.8 (4.4–5.4)
4.9 (4.4–5.4)
4.6 (4.1–5.5)
EGFR mut evaluable
All patients
Low EGFR IHC score
High EGFR IHC score / 482
333
148 / 4.6 (4.2–5.2)
4.3 (3.9–5.2)
4.9 (4.2–5.5) / 489
349
140 / 4.9 (4.4–5.4)
4.8 (4.3–5.4)
5.1 (4.2–5.6)
EGFR wtb
All patients
Low EGFR IHC score
High EGFR IHC score / 416
292
123 / 4.2 (4.0–5.0)
4.2 (3.8–5.0)
4.6 (4.2–5.4) / 422
307
115 / 4.6 (4.2–5.3)
4.6 (4.2–5.4)
4.6 (3.5–5.5)
EGFR mut (anyb)
All patients
Low EGFR IHC score
High EGFR IHC score / 66
41
25 / 5.7 (4.8–6.9)
5.6 (3.5–6.9)
6.5 (4.8–9.2) / 67
42
25 / 5.5 (4.8–6.7)
5.5 (3.2–5.8)
6.6 (4.6–8.2)
EGFR no del exon 19/L858R
All patients
Low EGFR IHC score
High EGFR IHC score / 418
293
124 / 4.3 (4.1–5.0)
4.2 (3.8–5.0)
4.6 (4.2–5.4) / 429
312
117 / 4.6 (4.2–5.3)
4.5 (4.2–5.4)
5.1 (3.5–5.5)
EGFR mut, del exon 19 or L858R
All patients
Low EGFR IHC score
High EGFR IHC score / 64
40
24 / 5.6 (4.4–6.9)
5.6 (3.1–6.9)
6.3 (4.8–9.2) / 60
37
23 / 5.7 (4.8–6.8)
5.7 (4.8–6.7)
6.6 (4.5–8.2)
aLow EGFR IHC score <200; high EGFR IHC score ≥200.
bT790M not considered/assessed.
ITT, intention-to-treat; IHC, immunohistochemistry; mut, mutation; wt, wild-type; NR, not reached; del, deletion.
TABLE S2.Median time to treatment failure according to treatment arm, EGFR mutation group and EGFR expression group
Populationa / Chemotherapy+ cetuximab / Chemotherapy
alone
n / Median, months
(95% CI) / n / Median, months
(95% CI)
ITT
All patients
Low EGFR IHC score
High EGFR IHC score / 557
377
178 / 4.2 (3.9–4.4)
4.0 (3.2–4.4)
4.2 (4.1–5.3) / 568
399
167 / 3.7 (3.1–4.2)
3.5 (3.0–4.2)
4.0 (3.1–4.5)
EGFR mut evaluable
All patients
Low EGFR IHC score
High EGFR IHC score / 482
333
148 / 4.2 (3.7–4.3)
3.8 (3.1–4.3)
4.2 (4.1–5.3) / 489
349
140 / 3.5 (3.1–4.2)
3.3 (2.9–4.1)
4.1 (3.2–4.6)
EGFR wtb
All patients
Low EGFR IHC score
High EGFR IHC score / 416
292
123 / 3.8 (3.2–4.2)
3.7 (3.0–4.2)
4.2 (3.2–4.8) / 422
307
115 / 3.3 (2.9–4.0)
3.3 (2.9–4.1)
3.4 (2.8–4.5)
EGFR mut (anyb)
All patients
Low EGFR IHC score
High EGFR IHC score / 66
41
25 / 5.6 (4.4–6.8)
4.8 (2.8–6.8)
6.5 (4.8–9.2) / 67
42
25 / 4.6 (3.2–5.4)
3.5 (2.5–5.4)
5.1 (4.2–8.2)
EGFR no del exon 19/L858R
All patients
Low EGFR IHC score
High EGFR IHC score / 418
293
124 / 3.9 (3.3–4.2)
3.7 (3.0–4.2)
4.2 (3.2–4.9) / 429
312
117 / 3.3 (2.9–4.0)
3.2 (2.9–4.1)
3.4 (2.9–4.6)
EGFR mut, del exon 19 or L858R
All patients
Low EGFR IHC score
High EGFR IHC score / 64
40
24 / 5.5 (4.2–6.8)
4.6 (2.4–6.8)
6.3 (4.8–9.2) / 60
37
23 / 5.0 (4.1–5.7)
4.8 (2.8–5.7)
5.1 (4.4–8.0)
aLow EGFR IHC score <200; high EGFR IHC score ≥200.
bT790M not considered/assessed.
ITT, intention-to-treat; IHC, immunohistochemistry; mut, mutation; wt, wild-type; NR, not reached; del, deletion.
TABLE S3. Overall response rate according to treatment arm, EGFR mutation group and EGFR expression group
Populationa / Chemotherapy+ cetuximab / Chemotherapy
alone
n / Response rate, % (95% CI) / n / Response rate, % (95% CI)
ITT
All patients
Low EGFR IHC score
High EGFR IHC score / 203/557
123/377
79/178 / 36.4 (32.4–40.6)
32.6 (27.9–37.6)
44.4 (37.0–52.0) / 166/568
118/399
47/167 / 29.2 (25.5–33.2)
29.6 (25.1–34.3)
28.1 (21.5–35.6)
EGFR mut evaluable
All patients
Low EGFR IHC score
High EGFR IHC score / 173/482
106/333
66/148 / 35.9 (31.6–40.4)
31.8 (26.9–37.1)
44.6 (36.4–53.0) / 138/489
96/349
42/140 / 28.2 (24.3–32.4)
27.5 (22.9–32.5)
30.0 (22.6–38.3)
EGFR wtb
All patients
Low EGFR IHC score
High EGFR IHC score / 137/416
88/292
48/123 / 32.9 (28.4–37.7)
30.1 (24.9–35.8)
39.0 (30.4–48.2) / 114/422
83/307
31/115 / 27.0 (22.8–31.5)
27.0 (22.1–32.4)
27.0 (19.1–36.0)
EGFR mut (anyb)
All patients
Low EGFR IHC score
High EGFR IHC score / 36/66
18/41
18/25 / 54.5 (41.8–66.9)
43.9 (28.5–60.3)
72.0 (50.6–87.9) / 24/67
13/42
11/25 / 35.8 (24.5–48.5)
31.0 (17.6–47.1)
44.0 (24.4–65.1)
EGFR no del exon 19/L858R
All patients
Low EGFR IHC score
High EGFR IHC score / 139/418
89/293
49/124 / 33.3 (28.8–38.0)
30.4 (25.2–36.0)
39.5 (30.9–48.7) / 115/429
83/312
32/117 / 26.8 (22.7–31.3)
26.6 (21.8–31.9)
27.4 (19.5–36.4)
EGFR mut, del exon 19 or L858R
All patients
Low EGFR IHC score
High EGFR IHC score / 34/64
17/40
17/24 / 53.1 (40.2–65.7)
42.5 (27.0–59.1)
70.8 (48.9–87.4) / 23/60
13/37
10/23 / 38.3 (26.1–51.8)
35.1 (20.2–52.5)
43.5 (23.2–65.5)
aLow EGFR IHC score <200; high EGFR IHC score ≥200.
bT790M not considered/assessed.
ITT, intention-to-treat; IHC, immunohistochemistry; mut, mutation; wt, wild-type; NR, not reached; del, deletion.