Baseline characteristics in the first-line switch-maintenance and second-line subgroups

Characteristics1 L-mn subgroup (n = 90)2 L subgroup (n = 60)
Median age (IQR), years59 (52.0–67.0)62.5 (51.5–66.0)
Sex, n (%)
 Male68 (75.6)46 (76.7)
 Female22 (24.4)14 (23.3)
ECOG PS, n (%)
 037 (41.1)23 (38.3)
 153 (58.9)37 (61.7)
Geographic region, n (%)
 North America31 (34.4)32 (53.3)
 Asia34 (37.8)10 (16.7)
 Europe25 (27.8)18 (30.0)
Race, n (%)
 White44 (48.9)36 (60.0)
 Asian35 (38.9)13 (21.7)
 Black4 (4.4)4 (6.7)
 Other7 (7.8)7 (11.7)
Histology, n (%)
 Tubular18 (20.0)3 (5.0)
 Signet ring17 (18.9)13 (21.7)
 Mucinous4 (4.4)4 (6.7)
 Papillary1 (1.1)0
 Other/not specified1 (1.1)0
 Unknown37 (41.1)39 (65.0)
PD-L1 expression status based on ≥1% cutoff on tumor cells, n (%)
 PD-L1+26 (28.9)20 (33.3)
 PD-L1−51 (56.7)25 (41.7)
 Not evaluable13 (14.4)15 (25.0)
HER2 status, n (%)
 HER2−62 (68.9)29 (48.3)
 HER2+4 (4.4)5 (8.3)
 Unknown24 (26.7)26 (43.3)
Microsatellite status, n (%)
 Low1 (1.1)0
 Stable21 (23.3)17 (28.3)
 High2 (2.2)2 (3.3)
 Unknown66 (73.3)41 (68.3)
Prior gastrectomy, n (%)24 (26.7)14 (23.3)
Metastatic disease status at study entry, n (%)
 M05 (5.6)2 (3.3)
 M185 (94.4)58 (96.7)
Tumor size at baselinea
 Median (IQR), mm33 (19–52)44 (25–69.5)
 Unknown, n (%)1 (1.1)1 (1.7)
Best response to prior anticancer therapy, n (%)
 Complete response01 (1.7)
 Partial response25 (27.8)8 (13.3)
 Stable disease59 (65.6)23 (38.3)
 Progressive disease022 (36.7)
 Not evaluable or unknown6 (6.7)5 (8.3)
Prior anticancer therapy (any setting), n (%)90 (100)60 (100)
Number of prior lines of anticancer therapy for metastatic or locally advanced disease, n (%)
 01 (1.1)5 (8.3)
 187 (96.7)53 (88.3)
 22 (2.2)1 (1.7)
 Unknown01 (1.7)
Median prior lines (range)1.0 (0–2)1.0 (0–2)
Interval from end of prior chemotherapy to start of avelumab therapy
 Median (IQR), days45 (35–64)77 (49–135)
 Data missing, n (%)8 (8.9)15 (25.0)

aSum of the longest diameters of target lesions

Abbreviations: 1 L-mn first-line switch-maintenance, 2 L second line, ECOG PS Eastern Cooperative Oncology Group performance status, IQR interquartile range