Introduction
Materials and methods
Patients
Study treatment
Outcomes and assessments
Statistical analysis
Results
Characteristic | Cohort 2 N = 25 | Cohort 3 N = 31 |
---|---|---|
Male | 16 (64.0) | 19 (61.3) |
Age, median (range) (years) | 64 (21–82) | 62 (32–75) |
Race | ||
Asian | 17 (68.0) | 15 (48.4) |
White | 8 (32.0) | 16 (51.6) |
Region | ||
United States | 3 (12.0) | 12 (38.7) |
East Asia | 16 (64.0) | 13 (41.9) |
Rest of world | 6 (24.0) | 6 (19.4) |
ECOG performance status | ||
0 | 15 (60.0) | 14 (45.2) |
1 | 10 (40.0) | 17 (54.8) |
Metastatic stage | ||
M0 | 1 (4.0) | 5 (16.1) |
M1 | 24 (96.0) | 26 (83.9) |
Prior surgery for gastric cancer | 5 (20.0) | 12 (38.7) |
Histology, WHO classification | ||
Tubular adenocarcinoma | 22 (88.0) | 25 (80.6) |
Signet ring cell carcinoma | 2 (8.0) | 3 (9.7) |
Mixed carcinoma | 1 (4.0) | 2 (6.5) |
Other poorly cohesive carcinoma | 0 | 1 (3.2) |
PD-L1 expression | ||
CPS ≥ 1 | 16 (64.0) | 31 (100.0) |
CPS < 1 | 8 (32.0) | 0 |
Unknown | 1 (4.0) | 0 |
Treatment exposure and safety
Cohort 2
Treatment-related AEsan (%) | Cohort 2 N = 25 | |
---|---|---|
Any grade | Grade 3 | |
Any | 25 (100.0) | 15 (60.0) |
Hematologic | ||
Decreased neutrophil count | 21 (84.0) | 12 (48.0) |
Anemia | 5 (20.0) | 2 (8.0) |
Decreased platelet count | 8 (32.0) | 2 (8.0) |
Decreased WBC count | 4 (16.0) | 1 (4.0) |
Febrile neutropenia | 1 (4.0) | 1 (4.0) |
Nonhematologic | ||
Nausea | 13 (52.0) | 1 (4.0) |
Stomatitisb | 13 (52.0) | 5 (20.0) |
Decreased appetite | 11 (44.0) | 2 (8.0) |
Fatigue | 8 (32.0) | 2 (8.0) |
Diarrhea | 8 (32.0) | 0 |
Dysgeusia | 7 (28.0) | 0 |
Constipation | 6 (24.0) | 0 |
Vomiting | 6 (24.0) | 0 |
Hiccups | 5 (20.0) | 0 |
Malaise | 5 (20.0) | 0 |
Palmar–plantar erythrodysesthesia syndrome | 4 (16.0) | 2 (8.0) |
Alopecia | 4 (16.0) | 0 |
Peripheral sensory neuropathy | 4 (16.0) | 0 |
Hyperthyroidism | 4 (16.0) | 0 |
Maculopapular rash or rash | 4 (16.0) | 2 (8.0) |
Pyrexia | 3 (12.0) | 1 (4.0) |
Decreased weight | 3 (12.0) | 1 (4.0) |
Increased blood creatinine level | 3 (12.0) | 0 |
Mucosal inflammationc | 3 (12.0) | 0 |
Peripheral neuropathy | 3 (12.0) | 0 |
Increased weight | 3 (12.0) | 0 |
Hypophosphatemia | 1 (4.0) | 1 (4.0) |
Polymyalgia rheumatica | 1 (4.0) | 1 (4.0) |
Cohort 3
Treatment-related AEsan(%) | Cohort 3 N = 31 | |
---|---|---|
Any grade | Grade 3 | |
Any | 24 (77.4) | 6 (19.4) |
Fatigue | 8 (25.8) | 0 |
Pruritus | 7 (22.6) | 0 |
Pneumonitis | 4 (12.9) | 0 |
Bile duct obstruction | 1 (3.2) | 1 (3.2) |
Colitis | 1 (3.2) | 1 (3.2) |
Dehydration | 1 (3.2) | 1 (3.2) |
Diffuse uveal melanocytic proliferation | 1 (3.2) | 1 (3.2) |
Hyponatremia | 1 (3.2) | 1 (3.2) |
Neutropenia | 1 (3.2) | 1 (3.2) |
Rash | 1 (3.2) | 1 (3.2) |
Antitumor activity
Cohort 2
Category | Cohort 2 N = 25 | Cohort 3 N = 31 | ||
---|---|---|---|---|
n
| % (95% CIb) |
n
| % (95% CIb) | |
Objective response ratec | 15 | 60.0 (38.7–78.9) | 8 | 25.8 (11.9–44.6) |
Disease control rated | 20 | 80.0 (59.3–93.2) | 11 | 35.5 (19.2–54.6) |
Best overall response | ||||
Complete response | 1 | 4.0 (0.1–20.4) | 2 | 6.5 (0.8–21.4) |
Partial response | 14 | 56.0 (34.9–75.6) | 6 | 19.4 (7.5–37.5) |
Stable disease | 8 | 32.0 (14.9–53.5) | 9 | 29.0 (14.2–48.0) |
Progressive disease | 1 | 4.0 (0.1–20.4) | 12 | 38.7 (21.8–57.8) |
Nonevaluable/no assessment | 1 | 4.0 (0.1–20.4) | 2 | 6.5 (0.8–21.4) |
Median (range) time to response (months) | 2.1 (1.9–3.7) | 2.1 (1.5–6.2) | ||
Median (range) duration of response (months) | 4.6 (2.6–20.3+) | 9.6 (2.1–17.8+) |