Table 1.
Baseline characteristics of the included studies.
| Author | Year | Age | Region | Cancer type | ICI treatment | PPI treatment | No. of PPI | Patients | PPI exposure |
|---|---|---|---|---|---|---|---|---|---|
| Afzal et al. (15) | 2019 | 65 | America | Melanoma | PD-1, CTLA-4 | Omeprazole (majority) | 29 | 120 | Within |
| Chalabi et al. (19) | 2020 | NA | Worldwide | NSCLC | PD-L1 | Omeprazole, pantoprazole, lansoprazole, rabeprazole, esomeprazole, dexlansoprazole | 234 | 757 | Prior, within (30 days) |
| Failing et al. (21) | 2016 | 58 | America | Melanoma | CTLA-4 | Omeprazole (majority) | 17 | 80 | Within |
| Hakozaki et al. (22) | 2019 | 67 | Asia | NSCLC | PD-1 | NA | 47 | 90 | Prior (30 days) |
| Iglesias‐Santamaría (25) | 2019 | 66 | Europe | Multiple | ICI | NA | 78 | 102 | Within |
| Svaton et al. (30) | 2020 | 67 | Europe | NSCLC | PD-1 | Omeprazole, pantoprazole, lansoprazole | 64 | 224 | Prior, Within (30 days) |
| Zhao et al. (31) | 2019 | 62 | Asia | NSCLC | PD-1, other | NA | 40 | 109 | Prior, Within (30 days) |
| Hopkins et al. (23) | 2020 | 68 | Worldwide | UC | PD-L1 | Meprazole, pantoprazole, lansoprazole, rabeprazole, esomeprazole, dexlansoprazole | 471 | 1360 | Prior, Within (30 days) |
| Cortellini et al. (20) | 2020 | 69 | Europe | Multiple | PD-(L)1 | NA | 491 | 1012 | Within |
| Husain et al. (24) | 2021 | 62 | America | Multiple | ICI | NA | 415 | 1091 | Within |
| Stokes et al (29). | 2021 | 69 | America | NSCLC | PD-(L)1 | Omeprazole (majority) | 2159 | 3634 | within (90 days) |
| Peng et al. (28) | 2021 | 64 | America | Multiple | PD-1, CTLA-4 | NA | 89 | 233 | Prior, Within (30 days) |
| Jun et al. (26) | 2021 | 66 | Worldwide | HCC | PD-1, CTLA-4, TKI | Omeprazole, pantoprazole, lansoprazole, rabeprazole, esomeprazole, dexlansoprazole | 85 | 314 | Prior (30 days) |
| Ruiz-Bañobre et al. (12) | 2021 | 69 | Europe | UC | PD-(L)1 | NA | 54 | 119 | Prior (30 days) |
| Araujo et al. (17) | 2021 | 59 | America | Multiple | ICI | NA | 57 | 216 | Prior (60 days) |
| Miura et al. (27) | 2021 | 65 | Asia | NSCLC | PD-1 | Lansoprazole, rabeprazole Esomeprazole | 163 | 300 | Within |
| Buti et al. (18) | 2021 | 69 | Europe | Multiple | ICI | NA | 104 | 217 | Within |
NSCLC, non-small cell lung cancer; PPI, proton pump inhibitor; UC, urothelial carcinoma; HCC, hepatocellular carcinoma; NA, not available; ICI, immune checkpoint inhibitor; CTLA-4, cytotoxic T-lymphocyte-associated antigen 4; PD-1, programmed cell death protein-1; PD-L1, programmed cell death ligand 1.